/* ABC E-Learning – giao diện web (elearning.abctalent.edu.vn), theo bộ nhận diện ABC Talent.
 * Màu: Hồng sen #F05A94 (nút chính, mỗi màn một nút), Cam #F37053, Hồng #F58F98, Xám #A7A9AC; chữ màu than ấm.
 * Kiểu Apple: nền trung tính, luôn giao diện sáng, không quầng sáng quanh nút.
 * Tiêu đề, nút, giá: Comfortaa (font logo ABC Talent); nội dung: Quicksand. Vàng chỉ cho thành tích / sao. */
/* Comfortaa: font chữ logo ABC Talent (OFL). Một tệp Bold cho mọi độ đậm của tiêu đề. */
@font-face { font-family: "Comfortaa ABC"; src: url("../fonts/Comfortaa-Bold.woff2") format("woff2"); font-display: swap; }
@font-face { font-family: "Quicksand"; src: url("../fonts/Quicksand-Medium.woff2") format("woff2"); font-weight: 500; font-display: swap; }
@font-face { font-family: "Quicksand"; src: url("../fonts/Quicksand-SemiBold.woff2") format("woff2"); font-weight: 600; font-display: swap; }
@font-face { font-family: "Quicksand"; src: url("../fonts/Quicksand-Bold.woff2") format("woff2"); font-weight: 700; font-display: swap; }

:root {
  --sm-dem: #3A2E35; --sm-khoi: #D9563A; --sm-hong: #F05A94; --sm-hong-kem: #FFE3E6; --sm-vang: #FFC928;
  --sm-cam: #F37053; --sm-ngoc: #F58F98; --sm-oai: #FDEEF2;
  --sm-hong-dam: #D93F7A; --sm-hong-sau: #BE2F68; --sm-vang-chu: #7A5600; --sm-vang-nhat: #FFF6D6; --sm-ngoc-chu: #B83A68;

  --nen: #F9F6F7; --mat: #FFFFFF; --mat-2: #FCF8F9; --vien: rgba(58, 46, 53, .10); --vien-dam: rgba(58, 46, 53, .2);
  --chu: #2E262A; --chu-2: rgba(46, 38, 42, .70); --chu-3: rgba(46, 38, 42, .52);
  --tieu-de: var(--sm-dem); --nhan: var(--sm-khoi); --nhan-nhat: rgba(243, 112, 83, .10);
  --cta: var(--sm-hong-dam); --cta-hover: var(--sm-hong-sau); --lien-ket: var(--sm-ngoc-chu);
  --tot: #1E7A3C; --tot-nen: rgba(52, 199, 89, .14); --canh-bao: #9A4306; --canh-bao-nen: #FFF1E0;
  --loi: #C0123C; --loi-nen: #FFE3E6;
  --bong: 0 1px 2px rgba(58, 46, 53, .05), 0 6px 20px rgba(58, 46, 53, .06);
  --r: 18px; --r-sm: 12px;
  --chu-de: "Comfortaa ABC", "Quicksand", system-ui, sans-serif;
  --chu-than: "Quicksand", -apple-system, system-ui, "Segoe UI", sans-serif;
  color-scheme: light;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body { font: 500 16px/1.55 var(--chu-than); color: var(--chu); background: var(--nen); -webkit-font-smoothing: antialiased; }
a { color: var(--lien-ket); text-decoration: none; }
a:hover { text-decoration: underline; }
button, input, select, textarea { font: inherit; color: inherit; }
h1, h2, h3 { font-family: var(--chu-de); font-weight: 400; color: var(--tieu-de); letter-spacing: .005em; text-wrap: balance; margin: 0; }
h1 { font-size: clamp(30px, 4.4vw, 46px); line-height: 1.1; }
h2 { font-size: 24px; line-height: 1.2; }
h3 { font-size: 18px; }
p { text-wrap: pretty; }
.mo { color: var(--chu-3); }
.phu { color: var(--chu-2); }
.an { display: none !important; }
:focus-visible { outline: 3px solid rgba(243, 112, 83, .45); outline-offset: 2px; border-radius: 8px; }

/* ---------- thanh trên ---------- */
.dau { position: sticky; top: 0; z-index: 30; background: color-mix(in srgb, var(--nen) 82%, transparent);
  -webkit-backdrop-filter: saturate(180%) blur(18px); backdrop-filter: saturate(180%) blur(18px); border-bottom: .5px solid var(--vien); }
.dau__trong { max-width: 1200px; margin: 0 auto; padding: 10px 16px; display: flex; align-items: center; gap: 14px; }
.dau__logo { display: flex; align-items: center; gap: 10px; text-decoration: none !important; }
.dau__logo img { height: 34px; width: auto; display: block; }
.dau__nhan { font: 400 15px var(--chu-de); color: var(--sm-dem); background: var(--sm-oai); padding: 3px 10px; border-radius: 999px; }
.dau__menu { margin-left: auto; display: flex; align-items: center; gap: 4px; flex-wrap: wrap; justify-content: flex-end; }
.dau__menu a { color: var(--chu-2); font-weight: 600; font-size: 15px; padding: 8px 12px; border-radius: 10px; }
.dau__menu a:hover { background: var(--nhan-nhat); text-decoration: none; color: var(--tieu-de); }
.dau__menu a.dang-o { color: var(--tieu-de); background: var(--nhan-nhat); }
.dau__logo img.logo-trang { display: none; }
main { max-width: 1200px; margin: 0 auto; padding: 24px 16px 80px; }

/* ---------- nút: một hệ duy nhất ---------- */
.nut { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding: 0 20px; border-radius: 12px;
  border: 1.5px solid var(--vien-dam); background: var(--mat); color: var(--nhan); font: 400 17px var(--chu-de); letter-spacing: .01em;
  cursor: pointer; text-decoration: none !important; white-space: nowrap; transition: background .15s, transform .05s; }
.nut:hover { background: var(--nhan-nhat); }
.nut:active { transform: translateY(1px); }
.nut[disabled] { opacity: .5; cursor: not-allowed; }
.nut--chinh { background: var(--cta); border-color: var(--cta); color: #fff; }
.nut--chinh:hover { background: var(--cta-hover); border-color: var(--cta-hover); }
.nut--nhe { border-color: transparent; background: transparent; }
.nut--nho { min-height: 36px; padding: 0 14px; font-size: 15px; border-radius: 10px; }
.nut--rong { width: 100%; }
.nut--nguy { color: var(--loi); }

/* ---------- ô nhập ---------- */
.o { width: 100%; min-height: 44px; padding: 10px 14px; border-radius: 12px; border: 1.5px solid var(--vien-dam); background: var(--mat); font-weight: 600; }
textarea.o { min-height: 96px; resize: vertical; line-height: 1.5; }
.nhan-o { display: block; font-weight: 700; font-size: 14px; color: var(--chu-2); margin: 14px 0 6px; }
.goi-y { font-size: 13px; color: var(--chu-3); margin-top: 4px; }

/* ---------- thẻ ---------- */
.the { background: var(--mat); border-radius: var(--r); box-shadow: var(--bong); border: .5px solid var(--vien); padding: 20px; }
.chip { display: inline-flex; align-items: center; gap: 4px; padding: 3px 10px; border-radius: 999px; font-size: 13px; font-weight: 700;
  background: var(--nhan-nhat); color: var(--nhan); white-space: nowrap; }
.chip--vang { background: var(--sm-vang-nhat); color: var(--sm-vang-chu); }
.chip--tot { background: var(--tot-nen); color: var(--tot); }
.chip--canh-bao { background: var(--canh-bao-nen); color: var(--canh-bao); }
.chip--loi { background: var(--loi-nen); color: var(--loi); }
.chips { display: flex; flex-wrap: wrap; gap: 6px; }

/* ---------- đầu trang tìm giáo viên ---------- */
.mo-dau { display: grid; grid-template-columns: 1.2fr 1fr; gap: 32px; align-items: center; padding: 20px 0 28px; }
.mo-dau p { font-size: 18px; color: var(--chu-2); margin: 14px 0 0; max-width: 560px; }
.cam-ket { display: grid; gap: 10px; }
.cam-ket__muc { display: flex; gap: 12px; align-items: flex-start; background: var(--mat); border-radius: var(--r-sm); padding: 14px 16px; border: .5px solid var(--vien); }
.cam-ket__so { flex: none; width: 32px; height: 32px; border-radius: 10px; display: grid; place-items: center; font: 400 17px var(--chu-de);
  background: var(--sm-oai); color: var(--sm-dem); }
.cam-ket__muc b { display: block; color: var(--tieu-de); }
.cam-ket__muc span { font-size: 14px; color: var(--chu-2); }
@media (max-width: 860px) { .mo-dau { grid-template-columns: 1fr; gap: 18px; } }

.bo-loc { display: flex; flex-wrap: wrap; gap: 10px; align-items: end; padding: 14px; background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien);
  position: sticky; top: 58px; z-index: 10; box-shadow: var(--bong); }
.bo-loc label { display: grid; gap: 4px; font-size: 13px; font-weight: 700; color: var(--chu-3); flex: 1 1 160px; }
.bo-loc select { min-height: 40px; border-radius: 10px; border: 1.5px solid var(--vien-dam); background: var(--mat); padding: 0 10px; font-weight: 600; color: var(--chu); }
.dem-kq { margin: 18px 4px 10px; font-weight: 700; color: var(--chu-2); }

/* ---------- thẻ giáo viên trong danh sách ---------- */
.ds-gia-su { display: grid; gap: 16px; }
.the-gs { display: grid; grid-template-columns: 132px 1fr 220px; gap: 20px; padding: 20px; background: var(--mat); border-radius: var(--r);
  border: .5px solid var(--vien); box-shadow: var(--bong); }
.the-gs__anh { width: 132px; height: 132px; border-radius: 16px; object-fit: cover; display: block; background: var(--sm-oai); }
.the-gs__ten { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.the-gs__ten h3 { font-size: 22px; }
.the-gs__ten a { color: inherit; }
.the-gs__tieu-de { font-weight: 700; color: var(--chu); margin: 4px 0 8px; }
.the-gs__mo-ta { color: var(--chu-2); font-size: 15px; margin: 10px 0 0; display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.the-gs__so { display: flex; gap: 18px; margin-top: 10px; font-size: 14px; color: var(--chu-2); }
.the-gs__so b { color: var(--tieu-de); font-family: var(--chu-de); font-weight: 400; font-size: 17px; }
.the-gs__ben { display: flex; flex-direction: column; gap: 10px; }
.gia { font: 400 26px var(--chu-de); color: var(--tieu-de); line-height: 1; }
.gia small { font: 600 13px var(--chu-than); color: var(--chu-3); display: block; margin-top: 4px; }
@media (max-width: 860px) {
  .the-gs { grid-template-columns: 88px 1fr; }
  .the-gs__anh { width: 88px; height: 88px; }
  .the-gs__ben { grid-column: 1 / -1; flex-direction: row; flex-wrap: wrap; align-items: center; }
  .the-gs__ben .gia { flex-basis: 100%; }
  .the-gs__ben .nut { flex: 1 1 0; }
}

.anh-chu { display: grid; place-items: center; color: #fff; font: 400 40px var(--chu-de);
  background: linear-gradient(135deg, var(--sm-hong), var(--sm-khoi)); }

/* ---------- hồ sơ giáo viên ---------- */
.ho-so { display: grid; grid-template-columns: minmax(0, 1fr) 340px; gap: 28px; align-items: start; }
.ho-so > * { min-width: 0; }
.ho-so__dau { display: flex; gap: 20px; align-items: center; }
.ho-so__anh { width: 128px; height: 128px; border-radius: 20px; object-fit: cover; flex: none; }
.ho-so section { margin-top: 28px; }
.ho-so section h2 { margin-bottom: 10px; }
.van-ban { white-space: pre-line; color: var(--chu); }
.ben-dinh { position: sticky; top: 76px; display: grid; gap: 14px; }
.video { position: relative; aspect-ratio: 16 / 9; border-radius: var(--r); overflow: hidden; background: #000; }
.video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
@media (max-width: 920px) { .ho-so { grid-template-columns: minmax(0, 1fr); } .ben-dinh { position: static; } .ho-so__anh { width: 96px; height: 96px; } }

/* lịch giờ trống kiểu Preply: 7 cột ngày, mỗi giờ một nút */
.lich__dieu-khien { display: flex; align-items: center; gap: 8px; margin-bottom: 12px; }
.lich__dieu-khien b { margin-right: auto; }
.lich { display: grid; grid-template-columns: repeat(7, minmax(0, 1fr)); gap: 6px; }
.lich__cot { display: grid; gap: 6px; align-content: start; }
.lich__ngay { text-align: center; padding: 6px 0 8px; border-bottom: 2px solid var(--vien); margin-bottom: 4px; }
.lich__ngay b { display: block; font: 400 15px var(--chu-de); color: var(--tieu-de); }
.lich__ngay span { font-size: 12px; color: var(--chu-3); }
.o-gio { border: 1.5px solid var(--vien-dam); background: var(--mat); border-radius: 9px; padding: 6px 0; font-weight: 700; font-size: 14px; cursor: pointer; color: var(--chu); }
.o-gio:hover { border-color: var(--nhan); color: var(--nhan); }
.o-gio.chon { background: var(--sm-khoi); color: #fff; border-color: var(--sm-khoi); }
.lich__trong { font-size: 12px; text-align: center; color: var(--chu-3); padding: 8px 0; }
@media (max-width: 600px) { .lich { grid-template-columns: repeat(7, 74px); overflow-x: auto; padding-bottom: 6px; } }

/* ---------- hộp thoại ---------- */
dialog.hop { border: 0; padding: 0; border-radius: 22px; width: min(520px, calc(100vw - 32px)); background: var(--mat); color: var(--chu);
  box-shadow: 0 24px 80px rgba(40, 20, 30, .35); }
dialog.hop::backdrop { background: rgba(40, 24, 32, .45); -webkit-backdrop-filter: blur(4px); backdrop-filter: blur(4px); }
.hop__than { padding: 24px; max-height: calc(100vh - 80px); overflow: auto; }
.hop__than h2 { margin-bottom: 6px; }
.hop__nut { display: flex; gap: 10px; justify-content: flex-end; margin-top: 20px; flex-wrap: wrap; }
.cong-ph__q { font: 400 40px var(--chu-de); color: var(--tieu-de); text-align: center; margin: 16px 0 10px; }
.cong-ph input { text-align: center; font: 400 28px var(--chu-de); }
.thong-bao-loi { color: var(--loi); font-weight: 700; min-height: 1.4em; margin: 8px 0 0; }

/* ---------- thanh toán ---------- */
.tt { display: grid; grid-template-columns: 300px 1fr; gap: 28px; align-items: start; max-width: 860px; margin: 0 auto; }
.tt__qr { width: 100%; border-radius: 16px; background: #fff; display: block; aspect-ratio: 1 / 1.1; object-fit: contain; }
.dong { display: flex; justify-content: space-between; gap: 12px; padding: 10px 0; border-bottom: .5px solid var(--vien); }
.dong:last-child { border-bottom: 0; }
.dong span { color: var(--chu-3); }
.dong b { text-align: right; }
.nut-chep { border: 0; background: var(--nhan-nhat); color: var(--nhan); border-radius: 8px; padding: 2px 8px; margin-left: 6px; cursor: pointer; font-weight: 700; font-size: 13px; }
@media (max-width: 760px) { .tt { grid-template-columns: 1fr; } .tt__qr { max-width: 320px; margin: 0 auto; } }

/* ---------- danh sách buổi học ---------- */
.ds-buoi { display: grid; gap: 12px; }
.buoi { display: grid; grid-template-columns: 76px 1fr auto; gap: 16px; align-items: center; padding: 16px; background: var(--mat); border-radius: var(--r);
  border: .5px solid var(--vien); }
.buoi__ngay { text-align: center; background: var(--sm-oai); color: var(--sm-dem); border-radius: 14px; padding: 8px 4px; }
.buoi__ngay b { display: block; font: 400 26px var(--chu-de); line-height: 1; }
.buoi__ngay span { font-size: 12px; font-weight: 700; }
.buoi__tieu-de { font-weight: 700; }
.buoi__nut { display: flex; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
@media (max-width: 700px) { .buoi { grid-template-columns: 64px 1fr; } .buoi__nut { grid-column: 1 / -1; justify-content: flex-start; } }

.bang-trong { text-align: center; padding: 48px 16px; color: var(--chu-2); }
.bang-trong h2 { margin-bottom: 8px; }

.loading { display: flex; justify-content: center; padding: 60px; }
.loading::after { content: ""; width: 26px; height: 26px; border-radius: 50%; border: 3px solid var(--nhan-nhat); border-top-color: var(--nhan); animation: quay .8s linear infinite; }
@keyframes quay { to { transform: rotate(360deg); } }

.toast { position: fixed; left: 50%; bottom: 24px; transform: translate(-50%, 20px); opacity: 0; background: var(--sm-dem); color: #fff; padding: 12px 18px;
  border-radius: 14px; font-weight: 700; z-index: 100; transition: .25s; pointer-events: none; max-width: calc(100vw - 32px); }
.toast.hien { opacity: 1; transform: translate(-50%, 0); }

/* ---------- khu làm việc giáo viên / vận hành (kiểu Apple như quan-tri.css) ---------- */
.khu { display: grid; grid-template-columns: 220px 1fr; gap: 24px; align-items: start; }
.khu__ben { position: sticky; top: 76px; display: grid; gap: 2px; }
.khu__ben button { text-align: left; border: 0; background: none; padding: 9px 12px; border-radius: 10px; font-weight: 700; color: var(--chu-2); cursor: pointer;
  display: flex; justify-content: space-between; align-items: center; }
.khu__ben button:hover { background: var(--nhan-nhat); }
.khu__ben button.dang-o { background: var(--sm-khoi); color: #fff; }
.khu__ben .dem { font-size: 12px; background: var(--cta); color: #fff; border-radius: 999px; padding: 1px 8px; }
.khu__noi h1 { font-size: 30px; margin-bottom: 18px; }
@media (max-width: 800px) {
  .khu { grid-template-columns: 1fr; }
  .khu__ben { position: static; display: flex; overflow-x: auto; gap: 6px; }
  .khu__ben button { white-space: nowrap; }
}
.luoi-so { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 12px; margin-bottom: 20px; }
.o-so { background: var(--mat); border: .5px solid var(--vien); border-radius: var(--r-sm); padding: 14px 16px; }
.o-so span { font-size: 13px; color: var(--chu-3); font-weight: 700; }
.o-so b { display: block; font: 400 28px var(--chu-de); color: var(--tieu-de); }
.bang { width: 100%; border-collapse: collapse; background: var(--mat); border-radius: var(--r-sm); overflow: hidden; border: .5px solid var(--vien); font-size: 14px; }
.bang th, .bang td { padding: 10px 12px; text-align: left; border-bottom: .5px solid var(--vien); vertical-align: top; }
.bang th { font-size: 12px; color: var(--chu-3); background: var(--mat-2); }
.bang tr:last-child td { border-bottom: 0; }
.bang .so { text-align: right; font-variant-numeric: tabular-nums; white-space: nowrap; }
.cuon-ngang { overflow-x: auto; }
.hang-gio { display: grid; grid-template-columns: 110px 1fr; gap: 12px; align-items: start; padding: 12px 0; border-bottom: .5px solid var(--vien); }
.hang-gio__khung { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.khung { display: inline-flex; align-items: center; gap: 6px; background: var(--mat-2); border: 1px solid var(--vien); border-radius: 10px; padding: 4px 6px; }
.khung input { width: 96px; border: 0; background: transparent; font-weight: 700; }
.khung button { border: 0; background: none; cursor: pointer; color: var(--chu-3); font-size: 18px; line-height: 1; }
.luoi-form { display: grid; grid-template-columns: 1fr 1fr; gap: 0 16px; }
@media (max-width: 700px) { .luoi-form { grid-template-columns: 1fr; } .hang-gio { grid-template-columns: 1fr; } }
.chon-chip { display: flex; flex-wrap: wrap; gap: 8px; }
.chon-chip label { display: inline-flex; gap: 6px; align-items: center; border: 1.5px solid var(--vien-dam); border-radius: 999px; padding: 4px 12px; cursor: pointer; font-weight: 700; font-size: 14px; }
.chon-chip input { accent-color: var(--sm-khoi); }

/* ---------- điện thoại ---------- */
.dau__nhan { white-space: nowrap; }
.cam-ket__muc span, .goi-y, .phu, .the-gs__mo-ta { text-wrap: pretty; }
.cam-ket__muc span { display: block; }
@media (max-width: 700px) {
  .dau__trong { flex-wrap: wrap; gap: 6px 10px; padding: 8px 16px 6px; }
  .dau__menu { margin-left: 0; width: 100%; flex-wrap: nowrap; justify-content: flex-start; overflow-x: auto; scrollbar-width: none; }
  .dau__menu a { padding: 6px 10px; font-size: 14px; white-space: nowrap; }
  .bo-loc { position: static; }
  .bo-loc label { flex: 1 1 140px; }
  main { padding-top: 16px; }
}

/* =====================================================================
 * TRANG NỘI DUNG (trang chủ, Cách học, Trở thành giáo viên, Hỏi đáp, Chính sách) – học bố cục Preply, màu ABC E-Learning
 * ===================================================================== */
.trang-nd { max-width: 1120px; }
.trang-nd--hep { max-width: 820px; }
.nhan-tren { font: 700 13px var(--chu-than); letter-spacing: .06em; text-transform: uppercase; color: var(--nhan); margin: 0 0 10px; }
.phu.lon { font-size: 18px; line-height: 1.6; }
.hep { max-width: 640px; }
.nut--lon { min-height: 52px; padding: 0 28px; font-size: 19px; border-radius: 14px; }
.nut--phu { background: var(--sm-khoi); border-color: var(--sm-khoi); color: #fff; }
.nut--phu:hover { background: var(--sm-dem); border-color: var(--sm-dem); }
.nut--sang { background: #fff; border-color: #fff; color: var(--sm-dem); }
.nut--sang:hover { background: var(--sm-oai); }
.lien-ket-mui { font-weight: 700; color: var(--nhan); }
.lien-ket-mui::after { content: " ›"; }
.ghi-chu { margin-top: 18px; color: var(--chu-2); }
.khoi { margin: 72px 0; }
.khoi > h2, .dau-khoi h2 { font-size: clamp(26px, 3.2vw, 34px); margin-bottom: 14px; }
.khoi--nen { background: var(--mat); border-radius: 28px; padding: 44px clamp(20px, 4vw, 48px); border: .5px solid var(--vien); }
.khoi--cuoi { text-align: center; display: grid; justify-items: center; gap: 6px; padding: 8px 0 24px; }
.khoi--cuoi .phu { margin: 0 0 14px; }
.dau-khoi { display: flex; justify-content: space-between; align-items: baseline; gap: 16px; flex-wrap: wrap; }

/* hero */
.hero { display: grid; grid-template-columns: 1.1fr 1fr; gap: 48px; align-items: center; padding: 36px 0 12px; }
.hero h1 { font-size: clamp(34px, 5vw, 56px); }
.hero__mo-ta { font-size: 19px; line-height: 1.6; color: var(--chu-2); margin: 18px 0 26px; max-width: 560px; }
.hero__nut { display: flex; align-items: center; gap: 22px; flex-wrap: wrap; }
.hero__cam-ket { list-style: none; padding: 0; margin: 28px 0 0; display: flex; flex-wrap: wrap; gap: 8px 18px; color: var(--chu-2); font-weight: 600; font-size: 15px; }
.hero__cam-ket li::before { content: "✓"; color: var(--tot); font-weight: 800; margin-right: 6px; }

/* hình minh hoạ phòng học (dựng bằng HTML) */
.mo-phong { background: var(--mat); border-radius: 24px; border: .5px solid var(--vien); box-shadow: 0 30px 80px -30px rgba(58, 46, 53, .35); overflow: hidden; }
.mo-phong__thanh { display: flex; align-items: center; gap: 6px; padding: 12px 16px; background: var(--sm-dem); color: #fff; }
.mo-phong__thanh span { width: 10px; height: 10px; border-radius: 50%; background: rgba(255, 255, 255, .35); }
.mo-phong__thanh b { margin-left: 8px; font: 400 15px var(--chu-de); }
.mo-phong__than { padding: 22px; display: grid; gap: 16px; }
.mo-phong__dau { display: flex; align-items: center; gap: 10px; }
.mo-phong__dau b { font: 400 20px var(--chu-de); color: var(--tieu-de); }
.mo-phong__dong { display: grid; gap: 8px; }
.mo-phong__dong i { display: block; height: 10px; border-radius: 6px; background: var(--sm-oai); }
.mo-phong__the { display: flex; gap: 8px; flex-wrap: wrap; }
.mo-phong__ai { font-size: 13px; font-weight: 700; padding: 5px 12px; border-radius: 999px; }
.mo-phong__ai--gs { background: rgba(245, 143, 152, .14); color: var(--sm-ngoc-chu); }
.mo-phong__ai--hv { background: var(--sm-hong-kem); color: var(--sm-hong-sau); }
.mo-phong__phim { position: relative; display: flex; height: 110px; border-radius: 12px; overflow: hidden; border: 1.5px solid var(--vien-dam); background: #fff; }
.mo-phong__phim i { flex: 1; border-right: 1px solid rgba(58, 46, 53, .15); }
.mo-phong__phim i:last-of-type { border-right: 0; }
.mo-phong__phim i.den { position: absolute; top: 0; width: 7%; height: 62%; background: var(--sm-dem); border-radius: 0 0 6px 6px; border: 0; }
.mo-phong__phim i.sang-gs { background: linear-gradient(#fff, var(--sm-ngoc) 160%); }
.mo-phong__phim i.sang-hv { background: linear-gradient(#fff, var(--sm-hong) 160%); }
/* bước */
.buoc { list-style: none; padding: 0; margin: 28px 0 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.buoc li { background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien); padding: 24px; }
.buoc h3 { font-size: 21px; margin: 14px 0 8px; }
.buoc p { margin: 0; color: var(--chu-2); }
.buoc__so { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 12px; background: var(--sm-oai); color: var(--sm-dem); font: 400 20px var(--chu-de); }
.buoc-dai { list-style: none; padding: 0; margin: 0; display: grid; gap: 28px; }
.buoc-dai > li { display: grid; grid-template-columns: 48px 1fr; gap: 18px; }
.buoc-dai h2 { font-size: 26px; margin-bottom: 8px; }
.buoc-dai p { color: var(--chu-2); margin: 0 0 10px; }

.hai-cot { display: grid; grid-template-columns: 1fr 1.1fr; gap: 40px; align-items: start; }
.hai-cot--deu { grid-template-columns: 1fr 1fr; }
.loi-ich { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
.loi-ich li { display: grid; gap: 2px; padding: 16px 18px; border-radius: var(--r-sm); background: var(--nen); }
.loi-ich b { color: var(--tieu-de); }
.loi-ich span { color: var(--chu-2); font-size: 15px; }

/* giáo trình */
.gt-luoi { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 24px; }
.gt-the { background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien); padding: 24px; }
.gt-the h3 { font-size: 22px; margin-bottom: 12px; }
.gt-the ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.gt-the li { display: grid; gap: 2px; padding-left: 14px; border-left: 3px solid var(--sm-oai); }
.gt-the b { color: var(--tieu-de); }
.gt-the span { color: var(--chu-2); font-size: 15px; }

/* giáo viên nổi bật */
.gs-noi-bat { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 16px; }
.gs-nho { display: grid; gap: 10px; align-content: start; background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien); padding: 20px; color: var(--chu); }
.gs-nho:hover { text-decoration: none; border-color: var(--nhan); }
.gs-nho__anh { width: 72px; height: 72px; border-radius: 18px; object-fit: cover; }
.gs-nho > div { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.gs-nho b { font: 400 19px var(--chu-de); color: var(--tieu-de); }
.gs-nho p { margin: 0; color: var(--chu-2); font-size: 15px; }
.gs-nho__gia { font-weight: 700; color: var(--chu); }

/* bảo đảm, mời giáo viên */
.bao-dam { display: flex; justify-content: space-between; align-items: center; gap: 24px; flex-wrap: wrap; background: var(--sm-oai); border-radius: 28px; padding: 32px clamp(20px, 4vw, 44px); }
.bao-dam h2 { color: var(--sm-dem); font-size: clamp(24px, 3vw, 30px); margin-bottom: 8px; }
.bao-dam p { margin: 0; max-width: 680px; color: #5A4A52; }
.bao-dam .lien-ket-mui { color: var(--sm-dem); }
.moi-gs { display: flex; justify-content: space-between; align-items: center; gap: 24px; flex-wrap: wrap; background: var(--sm-dem); color: #fff; border-radius: 28px; padding: 36px clamp(20px, 4vw, 48px); }
.moi-gs h2 { color: #fff; font-size: clamp(26px, 3.2vw, 34px); margin-bottom: 8px; }
.moi-gs p { margin: 0; max-width: 640px; color: rgba(255, 255, 255, .82); }

.luoi-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 20px; }
.o-y { background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien); padding: 22px; }
.khoi--nen .o-y { background: var(--nen); border: 0; }
.o-y h3 { font-size: 18px; margin-bottom: 8px; }
.o-y p { margin: 0; color: var(--chu-2); font-size: 15px; }
.o-y--nhat { background: var(--sm-oai); border: 0; }
.o-y--nhat h3 { color: var(--sm-dem); }
.o-y--nhat p { color: #5A4A52; }

/* danh sách, hỏi đáp */
.danh-sach { padding-left: 20px; margin: 10px 0 0; display: grid; gap: 8px; color: var(--chu-2); }
.danh-sach.lon { font-size: 17px; }
.danh-sach b { color: var(--chu); }
.hoi-dap { display: grid; gap: 10px; margin-top: 18px; }
.hoi-dap details { background: var(--mat); border-radius: var(--r-sm); border: .5px solid var(--vien); }
.hoi-dap summary { list-style: none; cursor: pointer; padding: 16px 52px 16px 20px; font-weight: 700; color: var(--tieu-de); position: relative; }
.hoi-dap summary::-webkit-details-marker { display: none; }
.hoi-dap summary::after { content: "+"; position: absolute; right: 20px; top: 50%; transform: translateY(-50%); font: 400 24px var(--chu-de); color: var(--nhan); }
.hoi-dap details[open] summary::after { content: "−"; }
.hoi-dap details p { margin: 0; padding: 0 20px 18px; color: var(--chu-2); }

/* đầu trang con */
.dau-trang { text-align: center; display: grid; justify-items: center; gap: 4px; padding: 40px 0 8px; }
.dau-trang h1 { max-width: 820px; }
.dau-trang .phu { max-width: 680px; margin: 10px 0 22px; }
.dau-trang--trai { text-align: left; justify-items: start; }
.muc-luc { display: flex; flex-wrap: wrap; gap: 8px; }
.muc-luc a { padding: 6px 14px; border-radius: 999px; background: var(--mat); border: .5px solid var(--vien); font-weight: 700; font-size: 14px; color: var(--chu-2); }
.khoi-hd { margin: 44px 0; scroll-margin-top: 80px; }
.khoi-hd h2 { font-size: 26px; }
.tim-dau { padding: 12px 0 18px; }
.tim-dau .phu { margin: 8px 0 0; font-size: 17px; }

/* bậc giáo viên, đơn ứng tuyển */
.bac-ds { list-style: none; padding: 0; margin: 14px 0 0; display: grid; gap: 10px; }
.bac-ds li { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; padding: 14px 18px; border-radius: var(--r-sm); background: var(--mat); border: .5px solid var(--vien); }
.bac-ds b { font: 400 18px var(--chu-de); color: var(--tieu-de); }
.bac-ds span { color: var(--chu-2); }
.don-khung { display: grid; grid-template-columns: 1fr 1.6fr; gap: 36px; align-items: start; scroll-margin-top: 80px; }
.don-gioi-thieu h2 { font-size: clamp(26px, 3.2vw, 34px); margin-bottom: 10px; }
.don { padding: 26px; }
.don .nhan-o { margin-top: 12px; }
.don .nhan-o .o { margin-top: 6px; font-weight: 600; }
.chon-nhieu { border: 0; padding: 0; margin: 0; }
.chip-chon { display: inline-flex; align-items: center; cursor: pointer; }
.chip-chon input { position: absolute; opacity: 0; pointer-events: none; }
.chip-chon span { padding: 6px 14px; border-radius: 999px; border: 1.5px solid var(--vien-dam); font-weight: 700; font-size: 14px; color: var(--chu-2); }
.chip-chon input:checked + span { background: var(--nhan-nhat); border-color: var(--nhan); color: var(--tieu-de); }
.chip-chon input:focus-visible + span { outline: 3px solid rgba(243, 112, 83, .45); outline-offset: 2px; }
.an-bay { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.dong-y { display: flex; gap: 10px; align-items: flex-start; margin: 18px 0 4px; font-size: 14px; color: var(--chu-2); }
.dong-y input { margin-top: 3px; accent-color: var(--sm-khoi); width: 18px; height: 18px; flex: none; }
.don-xong { text-align: center; padding: 30px 10px; }
.don-xong h3 { font-size: 24px; margin-bottom: 8px; }

/* văn bản dài (chính sách) */
.van-ban-dai h1 { margin: 24px 0 8px; }
.van-ban-dai h2 { font-size: 22px; margin: 34px 0 10px; scroll-margin-top: 80px; }
.van-ban-dai ul { padding-left: 20px; display: grid; gap: 8px; color: var(--chu-2); }
.van-ban-dai p { color: var(--chu-2); }

/* chân trang */
.chan { background: var(--sm-dem); color: rgba(255, 255, 255, .78); margin-top: 40px; padding: 48px 16px 28px; }
.chan__trong { max-width: 1120px; margin: 0 auto; display: grid; grid-template-columns: 1.3fr 1fr 1fr 1.2fr; gap: 28px; }
.chan__thuong-hieu p { margin: 12px 0 0; max-width: 260px; font-size: 15px; }
.chan h3 { color: #fff; font-size: 16px; margin-bottom: 10px; }
.chan ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.chan a { color: rgba(255, 255, 255, .86); font-size: 15px; }
.chan a:hover { color: #fff; }
.chan__cuoi { max-width: 1120px; margin: 36px auto 0; padding-top: 18px; border-top: 1px solid rgba(255, 255, 255, .14); font-size: 13px; color: rgba(255, 255, 255, .6); }

@media (max-width: 900px) {
  .hero, .hai-cot, .hai-cot--deu, .gt-luoi, .don-khung { grid-template-columns: 1fr; }
  .hero { gap: 28px; }
  .buoc, .luoi-3, .gs-noi-bat { grid-template-columns: 1fr; }
  .chan__trong { grid-template-columns: 1fr 1fr; }
  .khoi { margin: 52px 0; }
}
@media (max-width: 560px) {
  .chan__trong { grid-template-columns: 1fr; }
  .hero__mo-ta, .phu.lon { font-size: 17px; }
  .buoc-dai > li { grid-template-columns: 1fr; gap: 10px; }
  .khoi--nen, .bao-dam, .moi-gs { border-radius: 22px; }
}
.ds-don { display: grid; gap: 12px; }
.don-vh__dau { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.don-vh__dau b { font: 400 18px var(--chu-de); color: var(--tieu-de); }

/* gói học */
.ds-goi { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 12px; }
.goi { display: grid; gap: 8px; padding: 18px; background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien); }
.goi--mo { opacity: .7; }
.goi__dau { display: flex; justify-content: space-between; gap: 8px; align-items: center; flex-wrap: wrap; }
.goi__dau b { font: 400 18px var(--chu-de); color: var(--tieu-de); }
.goi__so { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin: 4px 0; }
.goi__so div { background: var(--mat-2); border-radius: 12px; padding: 8px 10px; display: grid; }
.goi__so b { font: 400 22px var(--chu-de); color: var(--tieu-de); }
.goi__so span { font-size: 12px; color: var(--chu-3); font-weight: 700; }
.goi__so .goi__gap { background: var(--canh-bao-nen); }
.goi__so .goi__gap b { color: var(--canh-bao); }
.goi__nhac { color: var(--canh-bao); font-weight: 700; }
.goi .buoi__nut { justify-content: flex-start; }
@media (max-width: 460px) { .goi__so { grid-template-columns: 1fr 1fr; } }
.chon-goi { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.chon-goi .nut { flex-direction: column; gap: 0; min-height: 60px; padding: 6px 10px; }
.chon-goi small { font: 600 12px var(--chu-than); color: var(--chu-3); }


/* =====================================================================
 * GIAO DIỆN THEO SAYPIANO.COM + BỘ NHẬN DIỆN (trang 05 Màu sắc, 07 Ứng dụng) – chủ dự án 28/10:
 * logo lớn, nền chuyển màu Say, nút 3D có viền đáy, thẻ trắng viền đáy dày, mỗi mục một màu nhấn (--k),
 * nhân vật Gia đình Nốt Nhạc 3D, dải tím đậm có quầng hồng – xanh, chân trang tím đêm.
 * ===================================================================== */
:root {
  --cam-nang: #F37053; --troi: #FFE9E2; --oai: #FDEEF2; --hong-kem: #FFE3E6;
  --vien-3d: #F4E6EA; --vien-3d-day: #F1DCE3;
  --do: #F0503C; --re: #FF9A2E; --mi: #F5B800; --fa: #36C26B; --sol: #2F9BFF; --la: #5B5BE6; --si: #C25BE6;
  --chuyen-say: linear-gradient(120deg, #FFF6F2 0%, #FFEFF3 45%, #FDEEF2 100%);
  --chuyen-hong: linear-gradient(135deg, #F58F98 0%, #E54C86 55%, #D93F7A 100%);
  --chuyen-nhan: linear-gradient(135deg, #F37053 0%, #E0457F 60%, #3A2E35 100%);
}
body { background: #FFFFFF; }
/* thanh trên: logo lớn, liên kết giữa, bên phải "Trở thành giáo viên" | khối tài khoản tách riêng */
.dau { background: rgba(255, 255, 255, .94); border-bottom: 2px solid #F6EEF1; }
.dau__trong { max-width: 1200px; height: 76px; padding: 0 20px; gap: 18px; }
.dau__logo { gap: 10px; flex: none; }
.dau__logo img { height: 58px; width: auto; }
.dau__nhan { font: 400 15px var(--chu-de); color: #fff; background: var(--chuyen-nhan); padding: 4px 12px; border-radius: 999px; box-shadow: 0 3px 0 #241B20; }
.dau__menu { margin-left: 8px; flex: 1; justify-content: flex-start; flex-wrap: nowrap; gap: 2px; }
.dau__menu a { font-weight: 700; font-size: 16px; color: var(--chu-2); padding: 9px 14px; border-radius: 12px; white-space: nowrap; }
.dau__menu a.dang-o { background: var(--oai); color: var(--sm-dem); }
.dau__ben { display: flex; align-items: center; gap: 12px; flex: none; }
.dau__gach { width: 2px; height: 30px; border-radius: 2px; background: #F5E9EE; }
.nut-gs.dang-o { background: var(--oai); }
.tai-khoan { display: flex; align-items: center; gap: 8px; padding: 4px 4px 4px 4px; border-radius: 999px; background: #FCF6F8; border: 2px solid var(--vien-3d); }
.tai-khoan__chu { width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center; font: 400 17px var(--chu-de); color: #fff; background: var(--chuyen-hong); }
.nut-ra { display: inline-flex; align-items: center; gap: 6px; border: 0; background: #fff; color: #A0174F; font: 700 14px var(--chu-than);
  padding: 7px 12px; border-radius: 999px; cursor: pointer; box-shadow: 0 2px 0 var(--vien-3d-day); }
.nut-ra:hover { background: #FFF0F5; }
.nut-ra:active { transform: translateY(2px); box-shadow: none; }
/* nút 3D (viền đáy dày, nhấn xuống khi bấm) */
.nut { border: 2px solid var(--vien-3d); border-bottom-width: 5px; border-radius: 16px; background: #fff; color: var(--sm-khoi); min-height: 48px; padding: 0 22px;
  transition: transform .08s ease, border-bottom-width .08s ease, filter .15s ease, background .15s; }
.nut:hover { background: #FDF8F9; }
.nut:active { transform: translateY(3px); border-bottom-width: 2px; }
.nut--chinh { background: var(--chuyen-hong); border-color: #E54C86; border-bottom-color: #A3285A; color: #fff; text-shadow: 0 1px 0 rgba(150, 30, 80, .35); }
.nut--chinh:hover { background: var(--chuyen-hong); filter: brightness(1.05); border-color: #E54C86; border-bottom-color: #A3285A; }
.nut--phu { background: var(--chuyen-nhan); border-color: #D9563A; border-bottom-color: #241B20; color: #fff; }
.nut--phu:hover { background: var(--chuyen-nhan); filter: brightness(1.08); }
.nut--sang { background: #fff; border-color: #fff; border-bottom-color: #F1DCE3; color: var(--sm-dem); }
.nut--nho { min-height: 40px; padding: 0 16px; font-size: 15px; border-radius: 13px; border-bottom-width: 4px; }
.nut--lon { min-height: 58px; padding: 0 32px; font-size: 20px; border-radius: 18px; border-bottom-width: 6px; }
.nut--nhe { border-color: transparent; background: transparent; border-bottom-width: 2px; }
/* thẻ trắng viền đáy dày */
.the, .buoc li, .o-y, .gt-the, .gs-nho, .goi, .the-gs, .buoi, .bac-ds li, .the-phong, .hoi-dap details, .ds-don .the {
  border: 2px solid var(--vien-3d); border-bottom-width: 5px; border-radius: 22px; box-shadow: none; }
.hoi-dap details { border-bottom-width: 4px; border-radius: 18px; }
.o-y--nhat { border-color: #FBD9E3; }
input.o, select.o, textarea.o, .bo-loc select { border-width: 2px; border-color: var(--vien-3d); border-radius: 14px; }
.bo-loc { border: 2px solid var(--vien-3d); border-bottom-width: 5px; border-radius: 22px; box-shadow: none; }

/* nền chuyển màu Say cho phần đầu mỗi trang nội dung */
.trang-nd { position: relative; }
.trang-nd::before { content: ""; position: absolute; z-index: -1; left: 50%; top: -24px; transform: translateX(-50%); width: 100vw; height: 640px;
  background: radial-gradient(60% 70% at 85% 0%, rgba(240, 90, 148, .16), transparent 70%),
              radial-gradient(50% 60% at 10% 10%, rgba(255, 201, 40, .14), transparent 70%),
              linear-gradient(180deg, #FDF3F6 0%, rgba(255, 255, 255, 0) 100%); pointer-events: none; }
/* nhãn mục kiểu bộ nhận diện (số hồng) và tiêu đề có màu nhấn riêng */
.nhan-tren { color: #E54C86; letter-spacing: .04em; }
.khoi > h2, .dau-khoi h2, .khoi .hai-cot h2 { color: var(--k, var(--sm-dem)); }
.khoi { --k: var(--sm-dem); }

/* trang chủ – phần mở đầu */
.hero { padding: 56px 0 28px; gap: 56px; }
.hero h1 { font-size: clamp(38px, 5.4vw, 64px); line-height: 1.05; }
.hero h1 em { font-style: normal; background: var(--chuyen-hong); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero__cam-ket li::before { content: ""; display: inline-block; width: 20px; height: 20px; margin-right: 8px; vertical-align: -4px; border-radius: 50%;
  background: var(--fa) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6 12.5l4 4 8-9' fill='none' stroke='%23fff' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / 14px no-repeat; }
.hero__hinh { position: relative; }
.hero__hinh::before { content: ""; position: absolute; inset: -6% -4% -10%; border-radius: 50%; z-index: -1;
  background: radial-gradient(closest-side, #FFE3EF 0%, #FDEEF2 60%, rgba(253, 238, 242, 0) 100%); }
.mo-phong { border: 2px solid var(--vien-3d); border-bottom-width: 6px; box-shadow: 0 30px 60px -30px rgba(58, 46, 53, .35); }
.mo-phong__thanh { background: var(--chuyen-nhan); }
.nv { position: absolute; z-index: 2; filter: drop-shadow(0 12px 16px rgba(58, 46, 53, .18)); pointer-events: none; }
.nv--nhun { animation: nhun 4.2s ease-in-out infinite; }
.nv--nhun2 { animation: nhun 4.8s ease-in-out -1.3s infinite; }
@keyframes nhun { 50% { transform: translateY(-7px); } }
@media (prefers-reduced-motion: reduce) { .nv--nhun, .nv--nhun2 { animation: none; } }
.hero .nv-meo { width: 128px; left: -34px; top: -96px; }
.hero .nv-do { width: 104px; right: -28px; top: -54px; }

/* các bước: số mang màu bạn nốt */
.buoc li { position: relative; padding: 26px 22px 24px; }
.buoc__so { width: 46px; height: 46px; border-radius: 14px; color: #fff; font-size: 22px; background: var(--b, var(--sm-khoi)); box-shadow: 0 4px 0 rgba(0, 0, 0, .14); }
.buoc li:nth-child(1) { --b: var(--do); } .buoc li:nth-child(2) { --b: var(--re); } .buoc li:nth-child(3) { --b: var(--fa); }
.buoc h3 { font-size: 22px; color: var(--sm-dem); }
.buoc .nv { width: 84px; right: 10px; top: -36px; }

.khoi--nen { background: linear-gradient(160deg, #EEF8FF 0%, #FFFFFF 70%); border: 2px solid #CDEBFF; border-bottom-width: 6px; border-radius: 30px; position: relative; }
.loi-ich li { background: #fff; border: 2px solid #DDF0FF; border-bottom-width: 4px; border-radius: 18px; }
.loi-ich b { color: #B83A68; }
.khoi--nen .nv { width: 120px; right: -20px; top: -70px; }

/* giáo trình */
.gt-the { position: relative; padding-top: 26px; }
.gt-the h3 { display: inline-block; font-size: 20px; color: #fff; padding: 6px 16px; border-radius: 999px; margin-bottom: 16px; box-shadow: 0 4px 0 rgba(0, 0, 0, .12); }
.gt-the--lon h3 { background: var(--chuyen-nhan); }
.gt-the--tre h3 { background: var(--chuyen-hong); }
.gt-the li { border-left: 4px solid var(--c, var(--oai)); border-radius: 2px; padding-left: 14px; }
.gt-the--lon li:nth-child(1) { --c: var(--la); } .gt-the--lon li:nth-child(2) { --c: var(--si); }
.gt-the--tre li:nth-child(1) { --c: var(--do); } .gt-the--tre li:nth-child(2) { --c: var(--re); } .gt-the--tre li:nth-child(3) { --c: var(--fa); } .gt-the--tre li:nth-child(4) { --c: var(--sol); }
.gt-the .nv { width: 92px; right: -14px; top: -44px; }

.gs-nho__anh { border-radius: 20px; box-shadow: 0 4px 0 var(--vien-3d-day); }
.gs-nho { transition: transform .15s; }
.gs-nho:hover { transform: translateY(-3px); border-color: #F7C9D6; }

/* bảo đảm: dải hồng chuyển màu */
.bao-dam { background: var(--chuyen-hong); border-radius: 30px; box-shadow: 0 6px 0 #A3285A; position: relative; overflow: visible; }
.bao-dam h2, .bao-dam p, .bao-dam .lien-ket-mui { color: #fff; }
.bao-dam p { color: rgba(255, 255, 255, .92); }
.bao-dam .lien-ket-mui { background: rgba(255, 255, 255, .18); padding: 10px 16px; border-radius: 14px; }

/* phụ huynh yên tâm */
.o-y { position: relative; }
.o-y h3 { color: var(--sm-dem); }
.o-y__bieu { width: 44px; height: 44px; border-radius: 14px; display: grid; place-items: center; margin-bottom: 12px; color: #fff; background: var(--c, var(--fa)); box-shadow: 0 4px 0 rgba(0, 0, 0, .12); }
.o-y__bieu svg { width: 24px; height: 24px; }

/* mời giáo viên: dải cam → hồng sen của ABC Talent */
.moi-gs { position: relative; overflow: hidden; padding: 44px clamp(22px, 5vw, 56px);
  background: radial-gradient(60% 80% at 10% 0%, rgba(255, 255, 255, .18), transparent 70%),
              linear-gradient(135deg, #F37053 0%, #F05A94 100%);
  box-shadow: 0 6px 0 #BE2F68; }
.moi-gs p { color: #FFEAF0; }
.moi-gs .nv-hang { display: flex; align-items: flex-end; margin: -6px 0 -44px; }
.moi-gs .nv-hang img { width: 74px; margin-left: -12px; filter: drop-shadow(0 10px 14px rgba(0, 0, 0, .3)); }

/* hỏi đáp */
.hoi-dap summary::after { content: ""; width: 10px; height: 10px; border-right: 3px solid var(--sm-khoi); border-bottom: 3px solid var(--sm-khoi);
  transform: translateY(-70%) rotate(45deg); font: inherit; transition: transform .2s; }
.hoi-dap details[open] summary::after { content: ""; transform: translateY(-30%) rotate(-135deg); }

.khoi--cuoi { background: var(--chuyen-say); border-radius: 30px; border: 2px solid #F6DDEB; border-bottom-width: 6px; padding: 44px 20px 40px; position: relative; }
.khoi--cuoi .nv { width: 96px; bottom: -6px; }
.khoi--cuoi .nv-trai { left: 6%; } .khoi--cuoi .nv-phai { right: 6%; }

/* chân trang */
.chan { background: #241B20; }
.chan__thuong-hieu img { width: 170px; height: auto; }

/* đầu trang con + tìm giáo viên */
.dau-trang h1, .tim-dau h1 { font-size: clamp(34px, 4.6vw, 52px); }
.dau-trang .nv { position: static; width: 110px; margin-bottom: -8px; }
.the-gs { transition: transform .15s; }
.the-gs:hover { transform: translateY(-2px); border-color: #F7C9D6; }

@media (max-width: 1080px) { .dau__menu a { padding: 8px 10px; font-size: 15px; } .dau__logo img { height: 44px; } }
@media (max-width: 900px) {
  .dau__trong { height: auto; flex-wrap: wrap; padding: 10px 16px 8px; gap: 8px 12px; }
  .dau__menu { order: 3; margin: 0; width: 100%; flex: none; overflow-x: auto; scrollbar-width: none; }
  .dau__ben { margin-left: auto; }
  .hero .nv-meo { width: 96px; left: -6px; top: -72px; }
  .hero .nv-do { width: 80px; right: -6px; }
  .khoi--nen .nv, .gt-the .nv { right: 6px; }
}
@media (max-width: 560px) {
  .dau__logo img { height: 42px; }
  .dau__nhan { font-size: 13px; padding: 3px 9px; }
  .dau__gach { display: none; }
  .nut-gs { min-height: 36px; padding: 0 10px; font-size: 13px; border-bottom-width: 3px; }
  .nut-ra span { display: none; }
  .nut-ra { padding: 8px; }
  .tai-khoan__chu { display: none; }
  .tai-khoan { padding: 2px; }
  .moi-gs .nv-hang { display: none; }
  .buoc .nv { width: 70px; }
}
.moi-gs__phai { display: grid; justify-items: center; gap: 0; }
@media (max-width: 760px) { .khoi--cuoi .nv { display: none; } }
/* dải "Bạn dạy piano?": chữ bên trái, nút + các bạn nốt bên phải (chủ dự án 28/10) */
.moi-gs { display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 24px 40px; }
.moi-gs__phai { justify-items: center; align-self: stretch; align-content: center; }
.moi-gs .nv-hang { margin: 14px 0 -44px; }
@media (max-width: 760px) { .moi-gs { grid-template-columns: 1fr; } .moi-gs__phai { justify-items: start; } }

/* màn hẹp (rà 28/10): hộp bên của hồ sơ không được rộng hơn cột; nút gói học cho chữ xuống dòng */
.ben-dinh { grid-template-columns: minmax(0, 1fr); min-width: 0; }
.chon-goi .nut { white-space: normal; text-align: center; min-width: 0; padding: 8px 10px; }
.chon-goi small { white-space: normal; line-height: 1.3; }

/* điện thoại (rà 28/10): thẻ giáo viên – ảnh nhỏ cạnh tên, nội dung dùng hết bề ngang; bộ lọc 2 cột; dòng thanh toán không bẻ nhãn */
@media (max-width: 560px) {
  .the-gs { position: relative; grid-template-columns: minmax(0, 1fr); gap: 12px; padding: 18px; }
  .the-gs > a:first-child { position: absolute; left: 18px; top: 18px; }
  .the-gs__anh, .the-gs .anh-chu { width: 60px; height: 60px; border-radius: 16px; font-size: 28px; }
  .the-gs__ten { min-height: 60px; padding-left: 74px; align-content: center; row-gap: 4px; }
  .the-gs__ten h3 { flex-basis: 100%; font-size: 20px; line-height: 1.15; }
  .the-gs__so { gap: 14px; }
  .bo-loc { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 10px; padding: 12px; }
  .bo-loc label, .bo-loc select { min-width: 0; width: 100%; }
  .bo-loc label { flex: none; }
  .bo-loc label:first-child { grid-column: 1 / -1; }
  .dong { flex-wrap: wrap; }
  .dong > span { flex: none; white-space: nowrap; }
  .dong > b { flex: 1 1 60%; min-width: 0; }
}

/* vận hành / Góc giáo viên trên màn hẹp (rà 28/10): bảng cuộn ngang trong khung, không đẩy cả trang */
.khu { grid-template-columns: 220px minmax(0, 1fr); }
.khu__noi, .khu > * { min-width: 0; }
.cuon-ngang { overflow-x: auto; -webkit-overflow-scrolling: touch; max-width: 100%; }
@media (max-width: 760px) {
  .khu { grid-template-columns: minmax(0, 1fr); }
  .cuon-ngang .bang { min-width: 620px; }
}
@media (max-width: 760px) {
  .khu__noi > form.the { grid-template-columns: minmax(0, 1fr) !important; }   /* form thêm giáo viên: một cột */
}
.bang select.o { min-width: 150px; }

/* ---------- sổ học viên (CRM giáo viên) ---------- */
.chip--tim { background: var(--sm-oai); color: var(--sm-khoi); }
.dau-muc { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; margin-bottom: 6px; }
.dau-muc h1 { margin: 0; }
.lui-lai { display: inline-block; margin-bottom: 8px; font-weight: 700; color: var(--lien-ket); text-decoration: none; }
.hang-nut { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin: 10px 0; }
.ds-hv { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 300px), 1fr)); gap: 12px; margin-top: 14px; }
.the-hv { display: grid; gap: 8px; padding: 16px; background: var(--mat); border: 2px solid var(--vien-3d); border-bottom-width: 5px; border-radius: var(--r);
  color: inherit; text-decoration: none; transition: transform .15s; }
.the-hv:hover { transform: translateY(-2px); border-color: var(--vien-3d-day); }
.the-hv__dau { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.the-hv__dau b { font: 400 20px var(--chu-de); color: var(--tieu-de); margin-right: auto; }
.the-hv__dong { display: grid; grid-template-columns: 92px minmax(0, 1fr); gap: 8px; font-size: 14px; }
.the-hv__dong span { color: var(--chu-3); font-weight: 700; }
.the-hv__chan { display: flex; justify-content: space-between; gap: 8px; flex-wrap: wrap; font-size: 13px; color: var(--chu-3); font-weight: 700; }
.luoi-so--chu .o-so b { font: 700 16px/1.4 var(--chu-than); margin-top: 4px; }
.so-dau-bai { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.so-dau-bai > li { display: grid; grid-template-columns: 64px minmax(0, 1fr); gap: 14px; padding: 14px; background: var(--mat); border-radius: var(--r); border: .5px solid var(--vien); }
.so-dau-bai > li p { margin: 6px 0 0; }
.so-dau-bai__ngay { text-align: center; background: var(--sm-oai); color: var(--sm-dem); border-radius: 14px; padding: 8px 4px; align-self: start; }
.so-dau-bai__ngay b { display: block; font: 400 20px var(--chu-de); }
.so-dau-bai__ngay span { font-size: 12px; font-weight: 700; }
.so-dau-bai__bai { font-weight: 700; margin-bottom: 4px; }
.buoi__truoc { margin-top: 8px; padding: 8px 12px; background: var(--sm-oai); border-radius: var(--r-sm); font-size: 14px; color: #5A4A52; }
.buoi__truoc a { font-weight: 700; color: var(--lien-ket); }
.o-y.nho { padding: 10px 14px; font-size: 14px; margin: 8px 0; }
.chon-bai { display: grid; gap: 8px; }
.chon-bai__hai { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); gap: 8px; }
.o-nhip { display: flex; align-items: center; gap: 8px; margin: 8px 0; font-weight: 700; font-size: 14px; color: var(--chu-2); }
.o--so { width: 92px; min-width: 0; }
.lich-cd { display: grid; gap: 8px; justify-items: start; }
.lich-cd__dong { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; }
.lich-cd__dong .o { width: auto; min-width: 0; }
@media (max-width: 560px) { .chon-bai__hai { grid-template-columns: 1fr; } }

/* lịch tuần */
.lt-cuon { border-radius: var(--r); background: var(--mat); border: .5px solid var(--vien); }
.lt { display: grid; grid-template-columns: 46px repeat(7, minmax(96px, 1fr)); min-width: 760px; }
.lt-truc span { position: absolute; right: 6px; transform: translateY(-50%); font-size: 11px; color: var(--chu-3); font-weight: 700; }
.lt-truc span:first-child { transform: none; }
.lt-cot { border-left: .5px solid var(--vien); }
.lt-cot.is-hom-nay .lt-cot__dau { background: var(--sm-oai); }
.lt-cot__dau { height: 46px; display: grid; place-content: center; text-align: center; border-bottom: .5px solid var(--vien); font-size: 13px; }
.lt-cot__dau span { color: var(--chu-3); font-weight: 700; font-size: 12px; }
.lt-cot__than { position: relative; background: repeating-linear-gradient(to bottom, transparent 0 43px, var(--vien) 43px 44px); }
.lt-mo { position: absolute; left: 0; right: 0; background: rgba(52, 199, 89, .10); }
.lt-su { position: absolute; left: 3px; right: 3px; padding: 2px 6px; border-radius: 8px; font-size: 11px; line-height: 1.25; overflow: hidden;
  text-decoration: none; text-align: left; border: 0; cursor: pointer; display: block; font-family: inherit; }
.lt-su b, .lt-su span { display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.lt-su--online { background: var(--sm-khoi); color: #fff; }
.lt-su--online.is-qua { background: #E89AAE; }
.lt-su--co-so { background: var(--sm-vang); color: #3a2a00; }
.lt-su--ban { background: repeating-linear-gradient(135deg, #FFE3E6 0 6px, #FFD0D8 6px 12px); color: var(--loi); }
.chu-giai { display: flex; flex-wrap: wrap; gap: 14px; margin: 0 0 10px; font-size: 13px; font-weight: 700; color: var(--chu-2); }
.cg::before { content: ""; display: inline-block; width: 12px; height: 12px; border-radius: 4px; margin-right: 6px; vertical-align: -1px; }
.cg--mo::before { background: rgba(52, 199, 89, .3); }
.cg--online::before { background: var(--sm-khoi); }
.cg--co-so::before { background: var(--sm-vang); }
.cg--ban::before { background: #FFD0D8; }

/* báo cáo học tập (phụ huynh) */
.bc-dau { background: var(--chuyen-say); border-radius: var(--r); padding: 24px; margin-bottom: 18px; }
.bc-dau h1 { margin: 4px 0 6px; }
.bc-hien { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 240px), 1fr)); gap: 12px; margin: 16px 0; }
.bc-hien > div { background: var(--mat); border-radius: var(--r-sm); padding: 14px 16px; border: 2px solid var(--vien-3d); }
.bc-hien span { display: block; font-size: 13px; font-weight: 700; color: var(--chu-3); }
.bc-hien b { display: block; margin-top: 4px; }
p.chip { white-space: normal; max-width: 100%; }

/* ---------- tin nhắn học viên ↔ giáo viên (assets/js/tin-nhan.js) ---------- */
.tn { display: grid; grid-template-columns: 300px minmax(0, 1fr); height: min(640px, calc(100vh - 220px)); min-height: 420px;
  background: var(--mat); border: 2px solid var(--vien-3d, var(--vien)); border-radius: var(--r); overflow: hidden; }
.tn__ds { border-right: .5px solid var(--vien); overflow-y: auto; }
.tn__cuoc { display: grid; grid-template-columns: 44px minmax(0, 1fr) auto; gap: 10px; align-items: center; padding: 10px 12px;
  color: inherit; text-decoration: none !important; border-bottom: .5px solid var(--vien); }
.tn__cuoc:hover { background: var(--nhan-nhat); }
.tn__cuoc.dang-o { background: var(--nhan-nhat); }
.tn__cuoc img, .tn__cuoc .anh-chu, .tn__anh img, .tn__anh .anh-chu { width: 44px; height: 44px; border-radius: 50%; object-fit: cover; font-size: 20px; }
.tn__giua { display: grid; min-width: 0; }
.tn__giua b, .tn__cuoi { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.tn__cuoi { font-size: 14px; color: var(--chu-3); }
.tn__cuoc.chua-doc .tn__cuoi { color: var(--chu); font-weight: 700; }
.tn__phai { display: grid; justify-items: end; gap: 4px; font-size: 12px; color: var(--chu-3); font-weight: 700; }
.dem { display: inline-block; min-width: 20px; text-align: center; font: 700 12px/18px var(--chu-than); background: var(--nhan); color: var(--mat);
  border-radius: 999px; padding: 0 6px; }
.dau__menu .dem { background: var(--cta); color: #fff; margin-left: 6px; vertical-align: 1px; }
.khu__ben .dem { margin-left: 6px; }
.tn__khung { display: grid; grid-template-rows: auto minmax(0, 1fr) auto; min-height: 0; }
.tn__khung > .tn__chon { grid-row: 1 / -1; align-self: center; text-align: center; padding: 24px; }
.tn__dau { display: flex; align-items: center; gap: 10px; padding: 10px 14px; border-bottom: .5px solid var(--vien); }
.tn__dau b { font: 400 19px var(--chu-de); color: var(--tieu-de); }
.tn__anh img, .tn__anh .anh-chu { width: 36px; height: 36px; font-size: 16px; display: grid; }
.tn__lui { display: none; font: 700 28px/1 var(--chu-than); padding: 0 6px; text-decoration: none !important; color: var(--nhan); }
.tn__luong { overflow-y: auto; padding: 14px; display: flex; flex-direction: column; gap: 6px; }
.tn__trong { margin: auto; text-align: center; }
.tn__tin { display: grid; justify-items: start; max-width: 78%; }
.tn__tin.cua-toi { justify-items: end; align-self: flex-end; }
.tn__bong { padding: 8px 14px; border-radius: 18px 18px 18px 4px; background: var(--mat-2); border: 1px solid var(--vien);
  white-space: pre-wrap; overflow-wrap: anywhere; }
.tn__tin.cua-toi .tn__bong { background: var(--nhan); color: var(--mat); border-color: transparent; border-radius: 18px 18px 4px 18px; }
.tn__tin small { font-size: 11px; color: var(--chu-3); font-weight: 700; padding: 2px 6px; }
.tn__go { display: flex; gap: 8px; align-items: flex-end; padding: 10px 12px; border-top: .5px solid var(--vien); }
.tn__o { min-height: 44px !important; max-height: 140px; resize: none; }
.tn__gui { flex: none; width: 44px; height: 44px; border-radius: 50%; border: 0; background: var(--nhan); color: var(--mat);
  display: grid; place-items: center; cursor: pointer; }
.tn__gui[disabled] { opacity: .5; cursor: default; }
@media (max-width: 760px) {
  .tn { grid-template-columns: minmax(0, 1fr); height: calc(100vh - 200px); }
  .tn--mo .tn__ds, .tn:not(.tn--mo) .tn__khung { display: none; }
  .tn__ds { border-right: 0; }
  .tn__lui { display: inline-block; }
}
/* chia mục trên "Buổi học của tôi": Buổi học | Tin nhắn */
.chia-muc { display: inline-flex; gap: 4px; padding: 4px; background: var(--mat-2); border: .5px solid var(--vien); border-radius: 14px; margin: 8px 0 4px; }
.chia-muc a { padding: 8px 16px; border-radius: 11px; font-weight: 700; color: var(--chu-2); text-decoration: none !important; }
.chia-muc a.dang-o { background: var(--mat); color: var(--tieu-de); box-shadow: var(--bong); }
.chia-muc .dem { margin-left: 6px; }

/* =====================================================================
 * LỚP GIAO DIỆN ABC TALENT (theo abctalent.edu.vn): nền trắng thoáng, Quicksand cả tiêu đề (đậm 600),
 * chữ #131313 / #656565, nút hồng #F58F99 dạng viên thuốc, thanh menu hồng nhạt bo tròn, chân trang kem #F7F6F1,
 * điểm nhấn xanh lá #1B6E53. Không viền 3D, không đổ bóng khối. Đặt cuối tệp để đè các quy tắc cũ.
 * ===================================================================== */
:root {
  --abc-hong: #F58F99; --abc-hong-dam: #F05A94; --abc-hong-nhat: rgba(245, 143, 153, .08); --abc-hong-vien: rgba(245, 143, 153, .28);
  --abc-xanh: #1B6E53; --abc-kem: #F7F6F1; --abc-den: #131313; --abc-xam: #656565; --abc-vien: #EFE8E9;
  --chu-de: "Quicksand", system-ui, sans-serif;
  --nen: #FFFFFF; --chu: var(--abc-den); --chu-2: var(--abc-xam); --chu-3: #8A8A8A; --tieu-de: var(--abc-den);
  --cta: var(--abc-hong); --cta-hover: var(--abc-hong-dam); --lien-ket: #D9466F; --nhan: var(--abc-hong-dam);
  --vien: var(--abc-vien); --vien-3d: var(--abc-vien); --vien-3d-day: var(--abc-vien);
  --sm-dem: var(--abc-den); --sm-khoi: var(--abc-hong-dam);
  --chuyen-hong: linear-gradient(135deg, #F58F99 0%, #F05A94 100%);
  --chuyen-say: linear-gradient(160deg, #FFF5F5 0%, #FFFFFF 60%);
  --bong: 0 10px 30px -18px rgba(19, 19, 19, .18);
}
body { background: #fff; color: var(--abc-den); }
h1, h2, h3, .dau__nhan { font-family: var(--chu-de); font-weight: 600; letter-spacing: 0; }
h1 { font-weight: 700; }
h1 em, h1 .nhan-hong, .hero h1 span { color: var(--abc-hong); }

/* nút: viên thuốc phẳng */
.nut, .nut--nho, .nut--lon { border: 1.5px solid var(--abc-den); border-bottom-width: 1.5px; border-radius: 40px; background: #fff; color: var(--abc-den);
  box-shadow: none; text-shadow: none; font-weight: 600; transform: none; }
.nut:active { transform: none; border-bottom-width: 1.5px; }
.nut:hover { filter: none; background: var(--abc-hong-nhat); }
.nut--chinh, .nut--chinh:hover { background: var(--abc-hong); border-color: var(--abc-hong); color: #fff; text-shadow: none; }
.nut--chinh:hover { background: var(--abc-hong-dam); border-color: var(--abc-hong-dam); }
.nut--nhe { border-color: transparent; background: transparent; }
.nut--lon { font-size: 18px; min-height: 54px; }

/* thẻ: viền mảnh, bo 20px, bóng rất nhẹ */
.the, .buoc li, .o-y, .gt-the, .gs-nho, .goi, .the-gs, .buoi, .bac-ds li, .the-phong, .hoi-dap details, .ds-don .the, .bo-loc, .the-hv,
.mo-phong, .khoi--nen, .loi-ich li, .khoi--cuoi {
  border: 1px solid var(--abc-vien); border-bottom-width: 1px; border-radius: 20px; box-shadow: var(--bong); }
.khoi--nen { background: var(--abc-kem); }
.khoi--cuoi { background: var(--abc-hong-nhat); }
.buoc__so, .o-y__bieu, .gt-the h3, .gs-nho__anh { box-shadow: none; }
.buoc__so { background: var(--abc-hong); border-radius: 50%; }
.gt-the h3 { background: var(--abc-hong) !important; }
.bao-dam { background: var(--abc-kem); color: var(--abc-den); box-shadow: none; border: 1px solid var(--abc-vien); }
.bao-dam h2, .bao-dam h3, .bao-dam p { color: var(--abc-den); }
.bao-dam .nut { background: #fff; }

/* thanh trên: dải hồng nhạt bo tròn ở giữa (như abctalent.edu.vn) */
.dau { background: transparent; border-bottom: 0; -webkit-backdrop-filter: none; backdrop-filter: none; padding-top: 12px; }
.dau__trong { background: rgba(255, 241, 240, .94); -webkit-backdrop-filter: blur(14px); backdrop-filter: blur(14px);
  border-radius: 40px; height: 64px; max-width: 1180px; padding: 0 14px 0 22px; }
.dau__logo img { height: 40px; }
.dau__nhan { background: transparent; color: var(--abc-hong-dam); box-shadow: none; padding: 0; font-size: 14px; }
.dau__menu a { color: var(--abc-den); font-weight: 600; }
.dau__menu a.dang-o, .dau__menu a:hover { background: transparent; color: var(--abc-hong); text-decoration: none; }
@media (max-width: 760px) { .dau { padding: 8px 8px 0; } .dau__trong { height: auto; border-radius: 24px; padding: 8px 12px; } }

/* chân trang kem, chữ tối */
.chan { background: var(--abc-kem); color: var(--abc-xam); }
.chan h3 { color: var(--abc-den); }
.chan a { color: var(--abc-xam); }
.chan a:hover { color: var(--abc-hong); }
.chan__cuoi { color: var(--abc-xam); border-top-color: var(--abc-vien); }

/* dải mời / chọn lại giáo viên: hồng nhạt, chữ tối */
.moi-gs { background: var(--abc-hong-nhat); color: var(--abc-den); box-shadow: none; border: 1px solid var(--abc-hong-vien); }
.moi-gs h2 { color: var(--abc-den); }
.moi-gs p { color: var(--abc-xam); }

/* nhãn nhỏ phía trên tiêu đề và số liệu */
.nhan-tren, .hero__nhan { color: var(--abc-hong); letter-spacing: .04em; }
.so-lieu b, .the-gs__so b { color: var(--abc-xanh); }
:focus-visible { outline-color: rgba(245, 143, 153, .6); }
.khoi > h2, .dau-khoi h2, .khoi .hai-cot h2, .khoi--nen h2 { color: var(--abc-den); }
.bao-dam .lien-ket-mui { color: var(--abc-hong-dam); background: #fff; border: 1px solid var(--abc-hong-vien); border-radius: 40px; }