/* TOEIC Buổi Tối — hệ thống thiết kế dùng chung.
   Chủ đề: văn phòng phẩm đi thi (phiếu tô đáp án, bút bi xanh, dạ quang vàng, bàn học buổi tối).
   Mục lục: 1 token · 2 nền & chữ · 3 vỏ ứng dụng · 4 tiện ích · 5 component · 6 chi tiết đặc trưng
            (omr, mark, ruler) · 7 khối bài giảng · 8 lớp phủ (toast, modal) · 9 chuyển động.
   View chỉ thêm class có tiền tố riêng (home-, day-, learn-, prac-, tests-, qz-); không sửa file này. */

/* ───────────────────────── 1. Token ───────────────────────── */
:root {
  /* màu — sáng */
  --bg: #EEF2F6;
  --surface: #FFFFFF;
  --surface-2: #F6F8FB;
  --sunken: #E4E9F0;
  --ink: #14213D;
  --muted: #56627D;
  --line: #D2D9E5;
  --line-strong: #74819F;
  --brand: #2447D5;
  --on-brand: #FFFFFF;
  --brand-soft: #E3E9FD;
  --mark: #FFD23F;
  --on-mark: #3A2E00;
  --mark-soft: #FFF4C7;
  --mark-line: #E3C254;
  --ok: #167A47;
  --ok-ink: #0F6338;
  --ok-soft: #DDF3E6;
  --on-ok: #FFFFFF;
  --bad: #C2362B;
  --bad-ink: #A92C22;
  --bad-soft: #FCE4E1;
  --on-bad: #FFFFFF;
  --warn: #A66A12;
  --warn-ink: #7F4F08;
  --warn-soft: #FAEBD0;
  --sk-l: #2447D5;
  --sk-r: #0E8A7B;
  --sk-v: #B7791F;
  --sk-g: #A23E8C;
  --pencil: #2B3247;
  --on-pencil: #FFFFFF;
  --pencil-grain: rgba(255, 255, 255, 0.16);
  --focus: #2447D5;
  --overlay: rgba(20, 33, 61, 0.46);
  --shadow-1: 0 1px 2px rgba(20, 33, 61, 0.06), 0 4px 14px rgba(20, 33, 61, 0.07);
  --shadow-2: 0 2px 6px rgba(20, 33, 61, 0.08), 0 18px 48px rgba(20, 33, 61, 0.18);
  --logo-bg: #14213D;

  /* chữ */
  --font-display: "Bricolage Grotesque", "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-ui: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-en: "Source Serif 4", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, "Times New Roman", serif;
  --font-ipa: "Noto Sans", "Segoe UI", "Lucida Sans Unicode", sans-serif;
  --fs-xs: 0.78rem;    /* 12.5px — nhãn phụ */
  --fs-sm: 0.875rem;   /* 14px */
  --fs-md: 1rem;       /* 16px — chữ nền */
  --fs-lg: 1.125rem;   /* 18px */
  --fs-xl: 1.375rem;   /* 22px */
  --fs-2xl: 1.75rem;   /* 28px */
  --fs-3xl: 2.25rem;   /* 36px */
  --fs-num: 2.75rem;   /* 44px — số lớn */
  --lh-tight: 1.2;
  --lh-body: 1.6;

  /* khoảng cách, bo góc, kích thước vỏ */
  --s1: 4px;  --s2: 8px;  --s3: 12px; --s4: 16px; --s5: 20px;
  --s6: 24px; --s7: 32px; --s8: 40px; --s9: 56px;
  --r-sm: 6px; --r-md: 10px; --r-lg: 14px; --r-xl: 20px; --r-pill: 999px;
  --gutter: 16px;
  --side-w: 232px;
  --content-max: 880px;
  --topbar-h: 52px;
  --tabbar-h: 58px;
  --tap: 44px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #0E1424;
    --surface: #171F35;
    --surface-2: #1D2742;
    --sunken: #0A0F1C;
    --ink: #E9EDF8;
    --muted: #9BA7C4;
    --line: #2A3554;
    --line-strong: #6B7AA6;
    --brand: #8AA4FF;
    --on-brand: #0B1230;
    --brand-soft: #1E2A52;
    --mark: #FFD23F;
    --on-mark: #3A2E00;
    --mark-soft: #2F270B;
    --mark-line: #6B5716;
    --ok: #5BC98F;
    --ok-ink: #5BC98F;
    --ok-soft: #12301F;
    --on-ok: #0B1230;
    --bad: #FF8A7A;
    --bad-ink: #FF8A7A;
    --bad-soft: #3B1B18;
    --on-bad: #0B1230;
    --warn: #F0B95A;
    --warn-ink: #F0B95A;
    --warn-soft: #33270F;
    --sk-l: #8AA4FF;
    --sk-r: #4FCFBD;
    --sk-v: #E8B45A;
    --sk-g: #E48FD0;
    --pencil: #D5DBEC;
    --on-pencil: #0E1424;
    --pencil-grain: rgba(14, 20, 36, 0.16);
    --focus: #8AA4FF;
    --overlay: rgba(3, 6, 14, 0.68);
    --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.35), 0 6px 18px rgba(0, 0, 0, 0.3);
    --shadow-2: 0 2px 8px rgba(0, 0, 0, 0.45), 0 20px 56px rgba(0, 0, 0, 0.55);
    --logo-bg: #26335F;
  }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0E1424;
  --surface: #171F35;
  --surface-2: #1D2742;
  --sunken: #0A0F1C;
  --ink: #E9EDF8;
  --muted: #9BA7C4;
  --line: #2A3554;
  --line-strong: #6B7AA6;
  --brand: #8AA4FF;
  --on-brand: #0B1230;
  --brand-soft: #1E2A52;
  --mark: #FFD23F;
  --on-mark: #3A2E00;
  --mark-soft: #2F270B;
  --mark-line: #6B5716;
  --ok: #5BC98F;
  --ok-ink: #5BC98F;
  --ok-soft: #12301F;
  --on-ok: #0B1230;
  --bad: #FF8A7A;
  --bad-ink: #FF8A7A;
  --bad-soft: #3B1B18;
  --on-bad: #0B1230;
  --warn: #F0B95A;
  --warn-ink: #F0B95A;
  --warn-soft: #33270F;
  --sk-l: #8AA4FF;
  --sk-r: #4FCFBD;
  --sk-v: #E8B45A;
  --sk-g: #E48FD0;
  --pencil: #D5DBEC;
  --on-pencil: #0E1424;
  --pencil-grain: rgba(14, 20, 36, 0.16);
  --focus: #8AA4FF;
  --overlay: rgba(3, 6, 14, 0.68);
  --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.35), 0 6px 18px rgba(0, 0, 0, 0.3);
  --shadow-2: 0 2px 8px rgba(0, 0, 0, 0.45), 0 20px 56px rgba(0, 0, 0, 0.55);
  --logo-bg: #26335F;
}

@media (min-width: 900px) {
  :root { --gutter: 32px; }
}

/* ───────────────────────── 2. Nền & chữ ───────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 400 16px/1.6 var(--font-ui);
  -webkit-text-size-adjust: 100%;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  overflow-x: clip;
  overflow-wrap: break-word;
}

h1, h2, h3, h4, p, ul, ol, dl, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 700; line-height: var(--lh-tight); text-wrap: balance; letter-spacing: -0.01em; }
h1 { font-size: var(--fs-2xl); }
h2 { font-size: var(--fs-xl); }
h3 { font-size: var(--fs-lg); font-weight: 600; }
h4 { font-size: var(--fs-md); font-weight: 600; }
@media (min-width: 900px) { h1 { font-size: var(--fs-3xl); } }

a { color: var(--brand); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
strong, b { font-weight: 600; }
img, svg, video, canvas { max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; }
table { border-collapse: collapse; }
hr { border: 0; border-top: 1px solid var(--line); margin: 0; }
::selection { background: var(--mark); color: var(--on-mark); }

:focus { outline: none; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; border-radius: var(--r-sm); }
/* tiêu đề trang nhận tiêu điểm khi đổi màn hình — không cần viền */
h1[tabindex="-1"]:focus-visible, h2[tabindex="-1"]:focus-visible, .view:focus-visible, main:focus-visible { outline: none; }

/* chữ tiếng Anh để học — như chữ trong đề thi giấy */
.en { font-family: var(--font-en); font-size: 1.07em; line-height: 1.55; letter-spacing: 0; font-variant-numeric: lining-nums; }
.en strong, .en b { font-weight: 600; }
.ipa { font-family: var(--font-ipa); font-size: 0.94em; color: var(--muted); white-space: nowrap; }
.num { font-family: var(--font-display); font-weight: 700; font-variant-numeric: tabular-nums lining-nums; letter-spacing: -0.01em; }
.tnum { font-variant-numeric: tabular-nums lining-nums; }
.muted { color: var(--muted); }
.small { font-size: var(--fs-sm); }
.tiny { font-size: var(--fs-xs); }
.strong { font-weight: 600; }
.center { text-align: center; }
.prose { max-width: 68ch; }
.nowrap { white-space: nowrap; }
.eyebrow { font-size: var(--fs-xs); font-weight: 600; color: var(--muted); letter-spacing: 0.06em; text-transform: uppercase; }
.text-ok { color: var(--ok-ink); }
.text-bad { color: var(--bad-ink); }
.text-warn { color: var(--warn-ink); }
.text-brand { color: var(--brand); }

.sr-only {
  position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0;
}

.icon { width: 1.25em; height: 1.25em; flex: none; display: inline-block; vertical-align: -0.22em; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.icon-sm { width: 1em; height: 1em; vertical-align: -0.14em; }
.icon-lg { width: 1.75em; height: 1.75em; }
.icon-fill { fill: currentColor; }

/* ───────────────────────── 3. Vỏ ứng dụng ───────────────────────── */
.app { min-width: 0; }
.main-col { min-width: 0; }

.page {
  width: 100%;
  max-width: calc(var(--content-max) + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);                    /* gutter đặt MỘT lần ở đây */
  padding-block: var(--s4) calc(var(--tabbar-h) + var(--s7) + env(safe-area-inset-bottom, 0px));
}
.view { display: grid; gap: var(--s5); min-width: 0; grid-template-columns: minmax(0, 1fr); }
.view > * { min-width: 0; }

.skip-link {
  position: fixed; left: var(--s3); top: calc(var(--s3) + env(safe-area-inset-top, 0px)); z-index: 60;
  padding: var(--s3) var(--s4); border: 0; border-radius: var(--r-md); background: var(--brand); color: var(--on-brand); font-weight: 600;
  transform: translateY(-300%);
}
.skip-link:focus-visible { transform: none; }

/* thanh trên (mobile) */
.topbar {
  position: sticky; top: env(safe-area-inset-top, 0px); z-index: 20;
  display: flex; align-items: center; gap: var(--s2);
  height: var(--topbar-h); padding-inline: var(--gutter);
  background: var(--surface); border-bottom: 1px solid var(--line);
}
.topbar-brand { display: flex; align-items: center; gap: var(--s2); min-width: 0; flex: 1; color: var(--ink); text-decoration: none; min-height: var(--tap); }
.topbar-name { font-family: var(--font-display); font-weight: 700; font-size: var(--fs-md); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.topbar-stats { display: flex; align-items: center; gap: var(--s1); flex: none; }
.logo { flex: none; display: block; }

.meter {
  display: inline-flex; align-items: center; gap: 4px; min-height: 32px; padding: 0 var(--s2);
  border-radius: var(--r-pill); color: var(--ink); font-weight: 600; font-size: var(--fs-sm);
  font-variant-numeric: tabular-nums; text-decoration: none; white-space: nowrap;
}
.meter .icon { color: var(--muted); }
.meter-streak.is-on .icon { color: var(--warn); }
.meter-xp .icon { color: var(--brand); }
.sync {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  min-width: var(--tap); min-height: var(--tap); padding: 0; border: 0; background: none;
  color: var(--muted); border-radius: var(--r-pill); font-size: var(--fs-xs);
}
.sync[data-sync="synced"] { color: var(--ok-ink); }
.sync[data-sync="local-only"], .sync[data-sync="retry"] { color: var(--warn-ink); }
.sync[data-sync="saving"] .icon { animation: spin 1.1s linear infinite; }

/* thanh tab dưới (mobile) */
.tabbar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 30;
  display: grid; grid-template-columns: repeat(5, minmax(0, 1fr));
  background: var(--surface); border-top: 1px solid var(--line);
  padding-bottom: env(safe-area-inset-bottom, 0px);
  padding-inline: max(4px, env(safe-area-inset-left, 0px)) max(4px, env(safe-area-inset-right, 0px));
}
.tab-item {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 1px;
  min-height: var(--tabbar-h); padding: 6px 2px; border: 0; background: none;
  color: var(--muted); font-size: 0.72rem; font-weight: 500; line-height: 1.2; text-decoration: none;
}
.tab-ico { display: grid; place-items: center; width: 52px; height: 28px; border-radius: var(--r-pill); }
.tab-ico .icon { width: 22px; height: 22px; }
.tab-item.is-active { color: var(--brand); font-weight: 600; }
.tab-item.is-active .tab-ico { background: var(--brand-soft); }
.tab-item:focus-visible { outline-offset: -3px; }

/* sidebar (desktop) */
.side { display: none; }
.side-brand { display: flex; align-items: center; gap: var(--s3); padding: 0 var(--s2) var(--s4); color: var(--ink); text-decoration: none; }
.side-brand-text { font-family: var(--font-display); font-weight: 700; font-size: 1.15rem; line-height: 1.1; letter-spacing: -0.01em; }
.side-brand-text small { display: block; font-family: var(--font-ui); font-weight: 500; font-size: var(--fs-xs); color: var(--muted); letter-spacing: 0; margin-top: 2px; }
.side-nav { display: grid; gap: 2px; }
.side-group { margin: var(--s3) var(--s3) 2px; font-size: var(--fs-xs); font-weight: 600; color: var(--muted); letter-spacing: 0.06em; text-transform: uppercase; }
.side-link {
  display: flex; align-items: center; gap: var(--s3); min-height: 38px; padding: 0 var(--s3);
  border-radius: var(--r-md); color: var(--ink); font-size: 0.94rem; font-weight: 500; text-decoration: none;
}
.side-link .icon { color: var(--muted); width: 20px; height: 20px; }
.side-link:hover { background: var(--surface-2); }
.side-link.is-active { background: var(--brand-soft); color: var(--brand); font-weight: 600; }
.side-link.is-active .icon { color: var(--brand); }
.side-foot { margin-top: auto; padding-top: var(--s4); display: grid; gap: var(--s2); }
.side-user {
  display: grid; grid-template-columns: auto minmax(0, 1fr); align-items: center; gap: var(--s3);
  padding: 10px var(--s3); border: 1px solid var(--line); border-radius: var(--r-lg);
  color: var(--ink); text-decoration: none; background: var(--surface);
}
.side-user:hover { background: var(--surface-2); }
.side-user-name { font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.side-user-stats { display: flex; flex-wrap: wrap; gap: 0 10px; font-size: var(--fs-xs); color: var(--muted); font-variant-numeric: tabular-nums; }
.side-user-stats span { display: inline-flex; align-items: center; gap: 3px; white-space: nowrap; }
.side-sync { display: flex; align-items: center; gap: 6px; padding: 0 var(--s3); font-size: var(--fs-xs); color: var(--muted); min-height: 24px; }
.side-sync[data-sync="synced"] { color: var(--ok-ink); }
.side-sync[data-sync="local-only"], .side-sync[data-sync="retry"] { color: var(--warn-ink); }
.side-sync[data-sync="saving"] .icon { animation: spin 1.1s linear infinite; }

.avatar {
  display: grid; place-items: center; flex: none; width: 36px; height: 36px; border-radius: 50%;
  background: var(--brand-soft); color: var(--brand); font-family: var(--font-display); font-weight: 700; font-size: 1rem;
}
.avatar-lg { width: 56px; height: 56px; font-size: 1.5rem; }

@media (min-width: 900px) {
  .app { display: grid; grid-template-columns: var(--side-w) minmax(0, 1fr); align-items: start; }
  .side {
    display: flex; flex-direction: column;
    position: sticky; top: env(safe-area-inset-top, 0px);
    height: calc(100vh - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
    height: calc(100dvh - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
    overflow-y: auto; padding: var(--s5) var(--s3) var(--s4);
    background: var(--surface); border-right: 1px solid var(--line);
  }
  .topbar, .tabbar { display: none; }
  .page { padding-block: var(--s7) var(--s9); }
}

/* chưa có hồ sơ / màn chào: ẩn điều hướng. Chế độ tập trung (làm đề): ẩn điều hướng. */
.app.is-bare, .app.is-focus { display: block; }
.app.is-bare .side, .app.is-bare .tabbar, .app.is-bare .topbar,
.app.is-focus .side, .app.is-focus .tabbar, .app.is-focus .topbar { display: none; }
.app.is-bare .page, .app.is-focus .page { padding-bottom: calc(var(--s8) + env(safe-area-inset-bottom, 0px)); }

/* màn chờ tĩnh trước khi JS chạy */
.boot { display: grid; justify-items: center; gap: var(--s3); padding: 18vh var(--gutter) var(--s8); text-align: center; }
.boot-title { font-size: var(--fs-2xl); }
.boot-text { max-width: 34ch; color: var(--muted); }
.boot-wait { font-size: var(--fs-sm); color: var(--muted); }

/* đầu trang của mỗi màn hình */
.page-head { display: grid; gap: var(--s2); }
.page-back {
  display: inline-flex; align-items: center; gap: 2px; justify-self: start; min-height: 40px;
  margin-left: -8px; padding: 0 var(--s3) 0 var(--s1); border: 0; border-radius: var(--r-md); background: none;
  color: var(--muted); font-size: var(--fs-sm); font-weight: 600; text-decoration: none;
}
.page-back:hover { color: var(--ink); background: var(--sunken); }
.page-head-row { display: flex; align-items: flex-start; justify-content: space-between; gap: var(--s3) var(--s4); flex-wrap: wrap; }
.page-title { min-width: 0; }
.page-sub { color: var(--muted); max-width: 68ch; }
.page-actions { display: flex; align-items: center; gap: var(--s2); flex-wrap: wrap; }

.section { display: grid; gap: var(--s3); min-width: 0; }
.section-head { display: flex; align-items: baseline; justify-content: space-between; gap: var(--s3); flex-wrap: wrap; }
.section-title { font-size: var(--fs-lg); font-weight: 700; }

/* ───────────────────────── 4. Tiện ích bố cục ───────────────────────── */
.row { display: flex; align-items: center; gap: var(--s3); min-width: 0; }
.row-wrap { flex-wrap: wrap; }
.row-between { justify-content: space-between; }
.row-top { align-items: flex-start; }
.row-end { justify-content: flex-end; }
.col { display: flex; flex-direction: column; gap: var(--s3); min-width: 0; }
.grid { display: grid; gap: var(--s4); grid-template-columns: minmax(0, 1fr); min-width: 0; }
.grid > * { min-width: 0; }
.grid-2, .grid-3, .grid-4 { display: grid; gap: var(--s4); grid-template-columns: minmax(0, 1fr); }
.grid-2 > *, .grid-3 > *, .grid-4 > * { min-width: 0; }
.grid-auto { display: grid; gap: var(--s4); grid-template-columns: repeat(auto-fill, minmax(min(100%, 220px), 1fr)); }
.grid-auto > * { min-width: 0; }
.grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (min-width: 640px) {
  .grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}
.gap-0 { gap: 0; } .gap-1 { gap: var(--s1); } .gap-2 { gap: var(--s2); } .gap-3 { gap: var(--s3); }
.gap-4 { gap: var(--s4); } .gap-5 { gap: var(--s5); } .gap-6 { gap: var(--s6); } .gap-7 { gap: var(--s7); }
.grow { flex: 1 1 0; min-width: 0; }
.shrink-0 { flex: none; }
.mt-auto { margin-top: auto; }
.ml-auto { margin-left: auto; }
.w-full { width: 100%; }
.only-desktop { display: none; }
@media (min-width: 900px) { .only-desktop { display: revert; } .only-mobile { display: none !important; } }

/* ───────────────────────── 5. Component ───────────────────────── */

/* nút */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--s2);
  min-height: var(--tap); padding: 0 var(--s5); border: 1.5px solid transparent; border-radius: var(--r-md);
  background: none; color: var(--ink); font-family: var(--font-ui); font-size: var(--fs-md); font-weight: 600; line-height: 1.2;
  text-align: center; text-decoration: none; white-space: nowrap; user-select: none;
  transition: background-color 0.12s, border-color 0.12s, transform 0.06s;
}
.btn:active:not(:disabled) { transform: translateY(1px); }
.btn:disabled, .btn[aria-disabled="true"] { opacity: 0.5; cursor: not-allowed; }
.btn .icon { width: 1.15em; height: 1.15em; }
.btn-primary { background: var(--brand); color: var(--on-brand); }
.btn-primary:hover:not(:disabled) { filter: brightness(0.92); }
.btn-ghost { background: var(--surface); border-color: var(--line-strong); color: var(--ink); }
.btn-ghost:hover:not(:disabled) { background: var(--surface-2); border-color: var(--ink); }
.btn-quiet { color: var(--brand); padding-inline: var(--s3); }
.btn-quiet:hover:not(:disabled) { background: var(--brand-soft); }
.btn-danger { background: var(--bad); color: var(--on-bad); }
.btn-danger:hover:not(:disabled) { filter: brightness(0.92); }
.btn-lg { min-height: 52px; padding-inline: var(--s6); font-size: var(--fs-lg); border-radius: var(--r-lg); }
.btn-sm { min-height: 36px; padding-inline: var(--s3); font-size: var(--fs-sm); border-radius: var(--r-sm); }
.btn-block { display: flex; width: 100%; white-space: normal; }
.btn-icon { width: var(--tap); min-width: var(--tap); padding: 0; border-radius: var(--r-pill); }
.btn-icon.btn-sm { width: 36px; min-width: 36px; }
@media (max-width: 899px) { .btn-sm { min-height: 40px; } .btn-icon.btn-sm { width: 40px; min-width: 40px; } }
.btn.is-playing { background: var(--brand-soft); color: var(--brand); border-color: transparent; }

/* thẻ — chỉ dùng cho khối cần tách */
.card { display: grid; gap: var(--s3); padding: var(--s5); background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); min-width: 0; grid-template-columns: minmax(0, 1fr); }
.card > * { min-width: 0; }
.card-sunken { background: var(--sunken); border-color: transparent; }
.card-brand { background: var(--brand-soft); border-color: transparent; }
.card-flat { background: none; border-style: dashed; border-color: var(--line-strong); }
.card-pad-sm { padding: var(--s4); }
.card-head { display: flex; align-items: center; justify-content: space-between; gap: var(--s3); flex-wrap: wrap; }
.card-title { font-family: var(--font-display); font-size: var(--fs-lg); font-weight: 700; line-height: var(--lh-tight); }
a.card, button.card { color: inherit; text-decoration: none; text-align: left; font: inherit; cursor: pointer; }
a.card:hover, button.card:hover { border-color: var(--line-strong); background: var(--surface-2); }
@media (min-width: 900px) { .card { padding: var(--s6); } .card-pad-sm { padding: var(--s4); } }

/* chip & nhãn */
.chip {
  display: inline-flex; align-items: center; gap: 4px; min-height: 26px; padding: 2px 10px;
  border-radius: var(--r-pill); background: var(--sunken); color: var(--ink);
  font-size: var(--fs-xs); font-weight: 600; line-height: 1.3; white-space: nowrap; text-decoration: none; border: 0;
}
.chip .icon { width: 14px; height: 14px; }
.chip-brand { background: var(--brand-soft); color: var(--brand); }
.chip-ok { background: var(--ok-soft); color: var(--ok-ink); }
.chip-bad { background: var(--bad-soft); color: var(--bad-ink); }
.chip-warn { background: var(--warn-soft); color: var(--warn-ink); }
.chip-mark { background: var(--mark); color: var(--on-mark); }
.chip-line { background: none; box-shadow: inset 0 0 0 1px var(--line-strong); }
button.chip { cursor: pointer; min-height: 32px; }
button.chip:hover { box-shadow: inset 0 0 0 1.5px var(--ink); }
button.chip[aria-pressed="true"] { background: var(--pencil); color: var(--on-pencil); }

/* nhãn kỹ năng: chấm màu + chữ mực (màu kỹ năng không dùng làm màu chữ) */
.tag {
  display: inline-flex; align-items: center; gap: 6px; min-height: 22px; padding: 0 8px 0 7px;
  border-radius: var(--r-sm); box-shadow: inset 0 0 0 1px var(--line); background: var(--surface); color: var(--ink);
  font-size: var(--fs-xs); font-weight: 600; white-space: nowrap; --tag-c: var(--muted);
}
.tag::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--tag-c); flex: none; }
.tag-l { --tag-c: var(--sk-l); }
.tag-r { --tag-c: var(--sk-r); }
.tag-v { --tag-c: var(--sk-v); }
.tag-g { --tag-c: var(--sk-g); }

/* thanh tiến độ */
.bar { position: relative; height: 8px; border-radius: var(--r-pill); background: var(--sunken); --bar-c: var(--brand); min-width: 40px; }
.card-sunken .bar, .bar-on-sunken { background: var(--line); }
.bar-fill { display: block; height: 100%; width: 0; max-width: 100%; border-radius: inherit; background: var(--bar-c); transition: width 0.35s ease; }
.bar-sm { height: 5px; }
.bar-lg { height: 12px; }
.bar-ok { --bar-c: var(--ok); }
.bar-warn { --bar-c: var(--warn); }
.bar-bad { --bar-c: var(--bad); }
.bar-mark { --bar-c: var(--mark); }
.bar-l { --bar-c: var(--sk-l); }
.bar-r { --bar-c: var(--sk-r); }
.bar-v { --bar-c: var(--sk-v); }
.bar-g { --bar-c: var(--sk-g); }
.bar-goal { position: absolute; top: -4px; bottom: -4px; width: 2px; margin-left: -1px; background: var(--ink); border-radius: 1px; }
.bar-line { display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: var(--s3); }
.bar-line .bar-val { font-size: var(--fs-sm); font-weight: 600; font-variant-numeric: tabular-nums; min-width: 3.2ch; text-align: right; }

/* vòng tiến độ */
.ring { position: relative; display: inline-grid; place-items: center; width: var(--ring-size, 72px); height: var(--ring-size, 72px); flex: none; --ring-c: var(--brand); }
.ring svg { display: block; width: 100%; height: 100%; transform: rotate(-90deg); }
.ring-track { fill: none; stroke: var(--sunken); }
.card-sunken .ring-track { stroke: var(--line); }
.ring-arc { fill: none; stroke: var(--ring-c); stroke-linecap: round; transition: stroke-dashoffset 0.4s ease; }
.ring-label { position: absolute; inset: 0; display: grid; place-content: center; text-align: center; line-height: 1.1; }
.ring-value { font-family: var(--font-display); font-weight: 700; font-size: calc(var(--ring-size, 72px) * 0.27); font-variant-numeric: tabular-nums; }
.ring-sub { font-size: max(10.5px, calc(var(--ring-size, 72px) * 0.13)); color: var(--muted); }
.ring-ok { --ring-c: var(--ok); } .ring-warn { --ring-c: var(--warn); } .ring-bad { --ring-c: var(--bad); }
.ring-l { --ring-c: var(--sk-l); } .ring-r { --ring-c: var(--sk-r); } .ring-v { --ring-c: var(--sk-v); } .ring-g { --ring-c: var(--sk-g); }

/* số liệu */
.stat { display: grid; gap: 2px; min-width: 0; align-content: start; }
.stat-label { display: flex; align-items: center; gap: 6px; font-size: var(--fs-sm); color: var(--muted); font-weight: 500; }
.stat-value { font-family: var(--font-display); font-weight: 700; font-size: var(--fs-2xl); line-height: 1.1; font-variant-numeric: tabular-nums lining-nums; letter-spacing: -0.01em; }
.stat-value small { font-family: var(--font-ui); font-size: var(--fs-sm); font-weight: 500; color: var(--muted); letter-spacing: 0; margin-left: 2px; }
.stat-sub { font-size: var(--fs-sm); color: var(--muted); }
.stat-lg .stat-value { font-size: var(--fs-num); }

/* các bước trong ngày */
.steps { display: grid; gap: 0; counter-reset: step; }
.step { position: relative; }
.step + .step::before { content: ""; position: absolute; left: 17px; top: -10px; height: 20px; width: 2px; background: var(--line); }
.step.is-done + .step::before, .step.is-pass + .step::before, .step.is-fail + .step::before { background: var(--pencil); }
.step-link {
  display: grid; grid-template-columns: 36px minmax(0, 1fr) auto; align-items: center; gap: var(--s3);
  width: 100%; min-height: 60px; padding: var(--s2) var(--s2) var(--s2) 0; border: 0; border-radius: var(--r-md);
  background: none; color: var(--ink); text-align: left; text-decoration: none; font: inherit;
}
a.step-link:hover, button.step-link:hover:not(:disabled) { background: var(--surface-2); }
.step-dot {
  position: relative; z-index: 1; display: grid; place-items: center; width: 36px; height: 36px; border-radius: 50%;
  border: 1.5px solid var(--line-strong); background: var(--surface); color: var(--muted);
  font-family: var(--font-display); font-weight: 700; font-size: 0.95rem;
}
.step-dot .icon { width: 18px; height: 18px; stroke-width: 2.4; }
.step-main { display: grid; gap: 1px; min-width: 0; }
.step-title { font-weight: 600; }
.step-sub { font-size: var(--fs-sm); color: var(--muted); }
.step-meta { display: inline-flex; align-items: center; gap: var(--s2); font-size: var(--fs-sm); color: var(--muted); font-variant-numeric: tabular-nums; white-space: nowrap; }
.step.is-current .step-dot { border-color: var(--brand); border-width: 2px; color: var(--brand); box-shadow: 0 0 0 4px var(--brand-soft); }
.step.is-current .step-title { color: var(--brand); }
.step.is-done .step-dot { background: var(--pencil); border-color: var(--pencil); color: var(--on-pencil); }
.step.is-pass .step-dot { background: var(--ok); border-color: var(--ok); color: var(--on-ok); }
.step.is-fail .step-dot { background: var(--surface); border-color: var(--warn); color: var(--warn-ink); border-width: 2px; }
.step.is-locked .step-link { color: var(--muted); }
.step.is-locked .step-dot { border-style: dashed; }

/* tab trong trang */
.tabs { display: flex; gap: var(--s1); overflow-x: auto; scrollbar-width: none; border-bottom: 1px solid var(--line); max-width: 100%; }
.tabs::-webkit-scrollbar { display: none; }
.tab {
  flex: none; min-height: var(--tap); padding: 0 var(--s4); border: 0; border-bottom: 3px solid transparent; margin-bottom: -1px;
  background: none; color: var(--muted); font-weight: 600; font-size: 0.95rem; white-space: nowrap; text-decoration: none;
  display: inline-flex; align-items: center; gap: var(--s2);
}
.tab:hover { color: var(--ink); }
.tab[aria-selected="true"], .tab.is-active { color: var(--brand); border-bottom-color: var(--brand); }
.tab:focus-visible { outline-offset: -3px; }

/* chọn một trong vài phương án (trình độ, mục tiêu, tốc độ, Part…) */
.seg { display: inline-flex; flex-wrap: wrap; gap: 4px; padding: 4px; border-radius: var(--r-lg); background: var(--sunken); max-width: 100%; }
.seg-opt {
  flex: 1 1 auto; min-height: 40px; padding: 4px var(--s4); border: 0; border-radius: var(--r-md);
  background: none; color: var(--ink); font-weight: 600; font-size: 0.95rem; white-space: nowrap; font-variant-numeric: tabular-nums;
}
.seg-opt:hover { background: var(--line); }
.seg-opt[aria-checked="true"] { background: var(--surface); color: var(--brand); box-shadow: 0 0 0 1.5px var(--brand); }
.seg-block { display: flex; width: 100%; }
.seg-cards { display: grid; gap: var(--s2); padding: 0; background: none; border-radius: 0; grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr)); width: 100%; }
.seg-cards .seg-opt {
  display: grid; gap: 2px; justify-items: start; text-align: left; white-space: normal; min-height: 64px; padding: var(--s3) var(--s4);
  background: var(--surface); border: 1.5px solid var(--line-strong); border-radius: var(--r-lg); font-weight: 400;
}
.seg-cards .seg-opt:hover { border-color: var(--ink); background: var(--surface-2); }
.seg-cards .seg-opt[aria-checked="true"] { border-color: var(--brand); background: var(--brand-soft); box-shadow: 0 0 0 1px var(--brand); color: var(--ink); }
.seg-label { font-weight: 600; }
.seg-sub { font-size: var(--fs-sm); color: var(--muted); font-weight: 400; }
.seg-cards .seg-opt[aria-checked="true"] .seg-label { color: var(--brand); }
/* lựa chọn bị khóa (vd mức khó chưa có câu): mờ đi, không phản hồi rê chuột; phím mũi tên tự nhảy qua (ui.seg) */
.seg-opt:disabled { color: var(--muted); opacity: 0.55; cursor: not-allowed; }
.seg-opt:disabled:hover { background: none; }
.seg-cards .seg-opt:disabled { border-style: dashed; }
.seg-cards .seg-opt:disabled:hover { border-color: var(--line-strong); background: var(--surface); }

/* ô nhập */
.field { display: grid; gap: 6px; min-width: 0; align-content: start; }
.label { font-weight: 600; font-size: 0.95rem; }
.hint { font-size: var(--fs-sm); color: var(--muted); }
.field-error { font-size: var(--fs-sm); color: var(--bad-ink); font-weight: 500; }
.input, .select, .textarea {
  width: 100%; min-height: 48px; padding: 10px 14px; border: 1.5px solid var(--line-strong); border-radius: var(--r-md);
  background: var(--surface); color: var(--ink); font-size: 1rem; line-height: 1.4;
}
.input::placeholder, .textarea::placeholder { color: var(--muted); opacity: 1; }
.input:hover, .select:hover, .textarea:hover { border-color: var(--ink); }
.input:focus-visible, .select:focus-visible, .textarea:focus-visible { outline: 3px solid var(--focus); outline-offset: 1px; border-color: var(--brand); border-radius: var(--r-md); }
.input[aria-invalid="true"] { border-color: var(--bad); }
.input-lg { min-height: 56px; font-size: var(--fs-lg); padding-inline: var(--s4); }
.input-en { font-family: var(--font-en); font-size: 1.1rem; }
.input-wrap { position: relative; }
.input-wrap > .icon { position: absolute; left: 14px; top: 50%; transform: translateY(-50%); color: var(--muted); pointer-events: none; }
.input-wrap > .input { padding-left: 42px; }
.check { display: inline-flex; align-items: center; gap: var(--s3); min-height: var(--tap); cursor: pointer; }
.check input { width: 22px; height: 22px; accent-color: var(--brand); flex: none; margin: 0; }
.switch { position: relative; display: inline-flex; align-items: center; gap: var(--s3); min-height: var(--tap); cursor: pointer; }
.switch input { position: absolute; opacity: 0; width: 46px; height: 28px; margin: 0; cursor: pointer; }
.switch-track { position: relative; flex: none; width: 46px; height: 28px; border-radius: var(--r-pill); background: var(--line-strong); transition: background-color 0.15s; }
.switch-track::after { content: ""; position: absolute; top: 3px; left: 3px; width: 22px; height: 22px; border-radius: 50%; background: var(--surface); transition: transform 0.15s; }
.switch input:checked + .switch-track { background: var(--brand); }
.switch input:checked + .switch-track::after { transform: translateX(18px); background: var(--on-brand); }
.switch input:focus-visible + .switch-track { outline: 3px solid var(--focus); outline-offset: 2px; }

/* danh sách hàng */
.list { display: grid; border: 1px solid var(--line); border-radius: var(--r-lg); background: var(--surface); overflow: hidden; }
.list-item {
  display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: var(--s3);
  min-height: 56px; padding: var(--s3) var(--s4); border: 0; border-top: 1px solid var(--line);
  background: none; color: var(--ink); text-align: left; text-decoration: none; font: inherit; width: 100%;
}
.list-item:first-child { border-top: 0; }
a.list-item:hover, button.list-item:hover:not(:disabled) { background: var(--surface-2); }
.list-item:focus-visible { outline-offset: -3px; }
.list-ico { display: grid; place-items: center; width: 36px; height: 36px; border-radius: var(--r-md); background: var(--sunken); color: var(--muted); }
.list-main { display: grid; gap: 1px; min-width: 0; }
.list-title { font-weight: 600; }
.list-sub { font-size: var(--fs-sm); color: var(--muted); }
.list-end { display: inline-flex; align-items: center; gap: var(--s2); color: var(--muted); font-size: var(--fs-sm); white-space: nowrap; }
.list-item.is-locked { color: var(--muted); }
.list-plain { border: 0; border-radius: 0; background: none; }
.list-plain .list-item { padding-inline: 0; }

/* bảng — luôn nằm trong khung cuộn riêng */
.table-wrap { max-width: 100%; overflow-x: auto; border: 1px solid var(--line); border-radius: var(--r-md); background: var(--surface); -webkit-overflow-scrolling: touch; }
.table { width: 100%; font-size: 0.95rem; font-variant-numeric: tabular-nums; }
.table caption { caption-side: top; text-align: left; padding: var(--s3) var(--s4) var(--s2); font-weight: 600; }
.table th, .table td { padding: 10px var(--s4); text-align: left; vertical-align: top; border-top: 1px solid var(--line); }
.table thead th { border-top: 0; background: var(--sunken); font-size: var(--fs-sm); font-weight: 600; color: var(--ink); white-space: nowrap; }
.table tbody tr:first-child td, .table tbody tr:first-child th { border-top: 0; }
.table thead + tbody tr:first-child td, .table thead + tbody tr:first-child th { border-top: 1px solid var(--line); }
.table .is-num { text-align: right; }
.table-compact th, .table-compact td { padding: 6px var(--s3); }

/* thông báo trong trang */
.callout { display: grid; grid-template-columns: auto minmax(0, 1fr); gap: var(--s3); padding: var(--s4); border-radius: var(--r-lg); background: var(--sunken); color: var(--ink); }
.callout > .icon { margin-top: 2px; color: var(--muted); }
.callout-title { font-weight: 600; }
.callout-body { display: grid; gap: var(--s1); min-width: 0; }
.callout-tip { background: var(--brand-soft); }
.callout-tip > .icon, .callout-tip .callout-title { color: var(--brand); }
.callout-warn { background: var(--warn-soft); }
.callout-warn > .icon, .callout-warn .callout-title { color: var(--warn-ink); }
.callout-ok { background: var(--ok-soft); }
.callout-ok > .icon, .callout-ok .callout-title { color: var(--ok-ink); }
.callout-bad { background: var(--bad-soft); }
.callout-bad > .icon, .callout-bad .callout-title { color: var(--bad-ink); }

/* trạng thái: đang tải, lỗi, trống */
.loading { display: flex; align-items: center; justify-content: center; gap: var(--s3); min-height: 160px; color: var(--muted); }
.loading-dots { display: inline-flex; gap: 6px; }
.loading-dots i { width: 10px; height: 10px; border-radius: 50%; border: 1.5px solid var(--line-strong); animation: bubble 1.2s infinite ease-in-out; }
.loading-dots i:nth-child(2) { animation-delay: 0.15s; }
.loading-dots i:nth-child(3) { animation-delay: 0.3s; }
.loading-dots i:nth-child(4) { animation-delay: 0.45s; }
.loading-inline { min-height: 0; justify-content: flex-start; }
.empty, .error-box { display: grid; justify-items: center; gap: var(--s3); padding: var(--s8) var(--s4); text-align: center; }
.empty-ico, .error-ico { display: grid; place-items: center; width: 64px; height: 64px; border-radius: 50%; background: var(--sunken); color: var(--muted); }
.empty-ico .icon, .error-ico .icon { width: 28px; height: 28px; }
.error-ico { background: var(--bad-soft); color: var(--bad-ink); }
.error-box.is-pending .error-ico { background: var(--brand-soft); color: var(--brand); }

.empty-title, .error-title { font-family: var(--font-display); font-size: var(--fs-lg); font-weight: 700; }
.empty-text, .error-text { max-width: 44ch; color: var(--muted); }
.error-detail { max-width: 100%; font-size: var(--fs-xs); color: var(--muted); overflow-wrap: anywhere; }
.empty-actions, .error-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: var(--s2); margin-top: var(--s1); }
.empty-sm { padding-block: var(--s5); }

/* ảnh Part 1 (SVG đã lọc) */
.svg-photo { display: block; width: 100%; max-width: 480px; aspect-ratio: 16 / 10; border-radius: var(--r-md); border: 1px solid var(--line); background: var(--sunken); overflow: hidden; }
.svg-photo svg { display: block; width: 100%; height: 100%; }

/* ───────────────────────── 6. Chi tiết đặc trưng ───────────────────────── */

/* 6.1 Ô tô đáp án (phiếu OMR) */
.omr { display: grid; gap: var(--s2); min-width: 0; }
.omr-opt {
  position: relative; display: grid; grid-template-columns: 36px minmax(0, 1fr) auto; align-items: center; gap: var(--s3);
  width: 100%; min-height: 52px; padding: 7px var(--s3) 7px var(--s2); border: 1.5px solid transparent; border-radius: var(--r-lg);
  background: none; color: var(--ink); text-align: left; font: inherit; line-height: 1.45;
  transition: background-color 0.1s, border-color 0.1s;
}
.omr-bubble {
  display: grid; place-items: center; width: 36px; height: 36px; border-radius: 50%;
  border: 1.5px solid var(--line-strong); background: var(--surface); color: var(--muted);
  font-family: var(--font-display); font-weight: 700; font-size: 0.95rem; line-height: 1;
  transition: background-color 0.1s, border-color 0.1s, color 0.1s, transform 0.1s;
}
.omr-body { display: grid; gap: 2px; min-width: 0; }
.omr-text { min-width: 0; }
.omr-note { font-size: var(--fs-sm); color: var(--muted); }
.omr-flag { display: none; color: var(--muted); }
.omr-flag .icon { width: 20px; height: 20px; stroke-width: 2.4; }
/* di chuột */
.omr-opt:hover:not(:disabled):not([aria-disabled="true"]) { background: var(--surface-2); }
.omr-opt:hover:not(:disabled):not([aria-disabled="true"]) .omr-bubble { border-color: var(--ink); color: var(--ink); }
.omr-opt:active:not(:disabled):not([aria-disabled="true"]) .omr-bubble { transform: scale(0.94); }
/* đã chọn: tô chì đặc */
.omr-opt.is-selected { background: var(--surface); border-color: var(--pencil); }
.omr-opt.is-selected .omr-bubble {
  border-color: var(--pencil); color: var(--on-pencil); background-color: var(--pencil);
  background-image: repeating-linear-gradient(-52deg, transparent 0 2.5px, var(--pencil-grain) 2.5px 3.5px);
}
/* khóa: không chọn được nữa */
.omr.is-locked .omr-opt { cursor: default; }
.omr.is-locked .omr-opt:not(.is-selected):not(.is-correct):not(.is-wrong) { color: var(--muted); }
/* đã chấm: đúng */
.omr-opt.is-correct { border-color: var(--ok); background: var(--ok-soft); color: var(--ink); }
.omr-opt.is-correct .omr-bubble { border-color: var(--ok); background: var(--surface); background-image: none; color: var(--ok-ink); border-width: 2.5px; }
.omr-opt.is-correct.is-selected .omr-bubble { background: var(--ok); color: var(--on-ok); }
.omr-opt.is-correct .omr-flag { display: block; color: var(--ok-ink); }
/* đã chấm: chọn sai */
.omr-opt.is-wrong { border-color: var(--bad); background: var(--bad-soft); color: var(--ink); }
.omr-opt.is-wrong .omr-bubble { border-color: var(--bad); background: var(--bad); background-image: none; color: var(--on-bad); }
.omr-opt.is-wrong .omr-flag { display: block; color: var(--bad-ink); }
.omr-opt:focus-visible { outline-offset: 1px; border-radius: var(--r-lg); }

/* chỉ có vòng chữ, xếp ngang (Part 1–2, phiếu trả lời) */
.omr-inline { display: flex; flex-wrap: wrap; gap: var(--s3); }
.omr-inline .omr-opt { width: auto; min-height: 0; grid-template-columns: auto; padding: 6px; border-radius: var(--r-pill); }
.omr-inline .omr-bubble { width: 44px; height: 44px; font-size: 1.05rem; }
.omr-inline .omr-body, .omr-inline .omr-flag { display: none !important; }
/* hai cột khi đủ rộng */
@media (min-width: 640px) { .omr-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
/* nhỏ gọn (bảng xem lại) */
.omr-sm .omr-opt { min-height: 40px; grid-template-columns: 28px minmax(0, 1fr) auto; padding-block: 4px; }
.omr-sm .omr-bubble { width: 28px; height: 28px; font-size: 0.8rem; }

/* 6.2 Dạ quang */
.mark, mark {
  background-color: var(--mark); color: var(--on-mark); padding: 0.04em 0.26em; margin: 0 0.02em;
  border-radius: 0.22em 0.4em 0.28em 0.42em; -webkit-box-decoration-break: clone; box-decoration-break: clone; font-weight: 500;
}
.mark strong, mark strong { font-weight: 700; }

/* 6.3 Thước điểm 10–990 */
.ruler { position: relative; display: grid; gap: 0; padding-inline: 2px; min-width: 0; font-variant-numeric: tabular-nums; }
.ruler-top, .ruler-bottom { position: relative; height: 30px; }
.ruler-strip {
  position: relative; height: 40px; border: 1.5px solid var(--line-strong); border-radius: var(--r-sm);
  background: var(--surface);
}
.ruler-fill { position: absolute; left: 0; top: 0; bottom: 0; background: var(--brand-soft); border-radius: 4px 0 0 4px; }
.ruler-zone { position: absolute; top: 0; bottom: 0; background: var(--mark-soft); border-inline: 1px dashed var(--mark-line); }
.ruler-tick { position: absolute; top: 0; width: 1px; height: 7px; background: var(--line-strong); }
.ruler-tick.is-major { height: 12px; width: 1.5px; margin-left: -0.25px; background: var(--ink); }
.ruler-num { position: absolute; bottom: 3px; transform: translateX(-50%); font-size: 0.72rem; font-weight: 500; color: var(--muted); line-height: 1; }
.ruler-num.is-start { transform: none; margin-left: 4px; }
.ruler-num.is-end { transform: translateX(-100%); margin-left: -4px; }
/* kim hiện tại */
.ruler-needle { position: absolute; top: -5px; bottom: -5px; width: 3px; margin-left: -1.5px; border-radius: 2px; background: var(--brand); z-index: 2; box-shadow: 0 0 0 2px var(--surface); }
.ruler-needle::after { content: ""; position: absolute; left: 50%; bottom: -3px; width: 11px; height: 11px; margin-left: -5.5px; border-radius: 50%; background: var(--brand); border: 2px solid var(--surface); }
.ruler-now { position: absolute; top: 8px; transform: translateX(-50%); white-space: nowrap; font-size: var(--fs-sm); color: var(--ink); line-height: 1.3; }
.ruler-now b { font-family: var(--font-display); font-weight: 700; color: var(--brand); font-size: 1.05rem; }
/* cờ mục tiêu */
.ruler-pole { position: absolute; top: -30px; bottom: 0; width: 2px; margin-left: -1px; background: var(--ink); z-index: 1; }
.ruler-flag {
  position: absolute; top: 0; white-space: nowrap; height: 22px; padding: 0 9px 0 7px; display: inline-flex; align-items: center; gap: 4px;
  background: var(--mark); color: var(--on-mark); font-size: var(--fs-xs); font-weight: 600; line-height: 1;
  clip-path: polygon(0 0, 100% 0, calc(100% - 7px) 50%, 100% 100%, 0 100%);
  padding-right: 15px;
}
.ruler-flag b { font-family: var(--font-display); font-weight: 700; font-size: 0.9rem; }
.ruler-flag.is-end { transform: translateX(-100%); clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%, 7px 50%); padding: 0 7px 0 15px; }
.ruler-now.is-start { transform: translateX(-10px); }
.ruler-now.is-end { transform: translateX(calc(-100% + 10px)); }
.ruler-empty { position: absolute; top: 8px; left: 0; font-size: var(--fs-sm); color: var(--muted); }
.ruler-compact .ruler-bottom { height: 26px; }

/* ───────────────────────── 7. Khối bài giảng & kho tài liệu ───────────────────────── */
.blocks { display: grid; gap: var(--s4); max-width: 68ch; min-width: 0; grid-template-columns: minmax(0, 1fr); }
.blk-p { line-height: 1.7; }
.blk-h { font-size: var(--fs-lg); font-weight: 700; margin-top: var(--s3); }
.blocks > .blk-h:first-child { margin-top: 0; }
/* bảng trong bài giảng / kho tài liệu (mọi màn hình dùng ui.blocks): tiêu đề cột được xuống dòng, ô hẹp hơn trên điện thoại → bảng 3–4 cột vừa 360px */
.blocks .table thead th { white-space: normal; }
@media (max-width: 479px) { .blocks .table th, .blocks .table td { padding-inline: var(--s3); } }
.blk-rule { padding: var(--s3) var(--s4) var(--s4); border: 1px solid var(--mark-line); border-radius: var(--r-md); background: var(--mark-soft); color: var(--ink); }
.blk-rule-title { font-size: var(--fs-xs); font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink); padding-bottom: var(--s2); }
.blk-rule-line { padding: 7px 0; border-top: 1px solid var(--mark-line); font-weight: 500; font-variant-numeric: tabular-nums; }
.blk-ex { display: grid; border: 1px solid var(--line); border-radius: var(--r-md); background: var(--surface); }
.blk-ex-item { display: grid; grid-template-columns: auto minmax(0, 1fr); gap: var(--s1) var(--s2); align-items: start; padding: var(--s3) var(--s4) var(--s3) var(--s2); border-top: 1px solid var(--line); }
.blk-ex-item:first-child { border-top: 0; }
.blk-ex-item.no-audio { grid-template-columns: minmax(0, 1fr); padding-left: var(--s4); }
.blk-ex-body { display: grid; gap: 2px; min-width: 0; padding-top: 7px; }
.blk-ex-item.no-audio .blk-ex-body { padding-top: 0; }
.blk-ex-en { font-size: 1.12rem; }
.blk-ex-vi { color: var(--muted); font-size: 0.95rem; }
.blk-ex-note { font-size: var(--fs-sm); color: var(--ink); margin-top: 4px; padding-left: 10px; border-left: 3px solid var(--mark); }
.blk-list { display: grid; gap: var(--s2); padding-left: var(--s5); }
.blk-list li { position: relative; line-height: 1.6; }
.blk-list li::before { content: ""; position: absolute; left: -16px; top: 0.72em; width: 8px; height: 2px; border-radius: 1px; background: var(--line-strong); }
.blk-steps { display: grid; gap: var(--s3); counter-reset: blkstep; }
.blk-steps li { position: relative; padding-left: 40px; min-height: 28px; line-height: 1.6; counter-increment: blkstep; }
.blk-steps li::before {
  content: counter(blkstep); position: absolute; left: 0; top: 0; display: grid; place-items: center; width: 28px; height: 28px; border-radius: 50%;
  border: 1.5px solid var(--line-strong); background: var(--surface); color: var(--ink);
  font-family: var(--font-display); font-weight: 700; font-size: 0.82rem; line-height: 1;
}
.blk-summary { display: grid; gap: var(--s2); max-width: 68ch; padding: var(--s4); border-radius: var(--r-md); background: var(--sunken); }
.blk-summary li { display: grid; grid-template-columns: auto minmax(0, 1fr); gap: var(--s2); }
.blk-summary li .icon { color: var(--ok-ink); margin-top: 3px; }

/* ───────────────────────── 8. Lớp phủ ───────────────────────── */
/* thông báo nằm TRÊN cùng (ngay dưới header ở điện thoại): mọi nút chính của web dính ở đáy màn hình, toast ở đáy sẽ che chúng */
.toasts {
  position: fixed; left: 0; right: 0; z-index: 200; pointer-events: none;
  top: calc(var(--topbar-h) + var(--s2) + env(safe-area-inset-top, 0px));
  display: grid; justify-items: center; gap: var(--s2); padding-inline: var(--gutter);
}
.app.is-bare ~ .toasts, .app.is-focus ~ .toasts { top: calc(var(--s3) + env(safe-area-inset-top, 0px)); }
@media (min-width: 900px) { .toasts, .app.is-bare ~ .toasts, .app.is-focus ~ .toasts { top: calc(var(--s4) + env(safe-area-inset-top, 0px)); justify-items: end; padding-inline: var(--s6); } }
.toast {
  pointer-events: auto; display: flex; align-items: center; gap: var(--s3); max-width: min(100%, 460px);
  padding: 10px var(--s4); border: 1px solid var(--line-strong); border-radius: var(--r-lg);
  background: var(--surface); color: var(--ink); box-shadow: var(--shadow-2); font-size: 0.95rem; font-weight: 500;
  animation: toast-in 0.18s ease-out;
}
.toast > .icon { color: var(--muted); }
.toast-ok > .icon { color: var(--ok-ink); }
.toast-bad > .icon { color: var(--bad-ink); }
.toast-warn > .icon { color: var(--warn-ink); }
.toast-info > .icon { color: var(--brand); }
.toast-msg { min-width: 0; }
.toast-action { flex: none; min-height: 36px; padding: 0 var(--s3); border: 0; border-radius: var(--r-sm); background: none; color: var(--brand); font-weight: 600; }
.toast-action:hover { background: var(--brand-soft); }
.toast.is-leaving { opacity: 0; transition: opacity 0.18s; }

.has-modal body, body.has-modal { overflow: hidden; }
.modal-backdrop {
  position: fixed; inset: 0; z-index: 100; display: grid; place-items: center;
  padding: calc(var(--s4) + env(safe-area-inset-top, 0px)) var(--s4) calc(var(--s4) + env(safe-area-inset-bottom, 0px));
  background: var(--overlay); overflow-y: auto; animation: fade-in 0.14s ease-out;
}
.modal {
  display: grid; grid-template-rows: auto minmax(0, 1fr) auto; width: 100%; max-width: 460px; max-height: 100%;
  background: var(--surface); color: var(--ink); border: 1px solid var(--line); border-radius: var(--r-xl); box-shadow: var(--shadow-2);
  animation: modal-in 0.18s ease-out;
}
.modal-sm { max-width: 380px; }
.modal-lg { max-width: 640px; }
.modal-head { display: flex; align-items: flex-start; justify-content: space-between; gap: var(--s3); padding: var(--s5) var(--s5) 0; }
.modal-title { font-size: var(--fs-xl); padding-top: 6px; }
.modal-x { margin: -4px -8px 0 0; color: var(--muted); }
.modal-body { display: grid; gap: var(--s3); padding: var(--s3) var(--s5) var(--s5); overflow-y: auto; min-height: 0; align-content: start; }
.modal-head + .modal-body { padding-top: var(--s3); }
.modal-body:first-child { padding-top: var(--s5); }
.modal-foot { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: var(--s2); padding: 0 var(--s5) var(--s5); }
.modal-foot .btn { flex: 0 1 auto; }
@media (max-width: 520px) { .modal-foot { flex-direction: column-reverse; } .modal-foot .btn { width: 100%; } }
/* bảng chọn trượt từ dưới lên (mobile) */
.modal-backdrop.is-sheet { place-items: end center; padding: env(safe-area-inset-top, 0px) 0 0; }
.is-sheet .modal { max-width: 560px; border-radius: var(--r-xl) var(--r-xl) 0 0; border-bottom: 0; padding-bottom: env(safe-area-inset-bottom, 0px); animation-name: sheet-in; }
@media (min-width: 900px) {
  .modal-backdrop.is-sheet { place-items: center; padding: var(--s4); }
  .is-sheet .modal { border-radius: var(--r-xl); border-bottom: 1px solid var(--line); padding-bottom: 0; animation-name: modal-in; }
}

/* vùng bấm ≥ 40px trên mobile cho mọi thứ bấm được (đặt sau các component để thắng thứ tự nguồn) */
@media (max-width: 899px) {
  button.chip, a.chip { min-height: 40px; padding-inline: 14px; }
  .meter { min-height: 40px; }
  .toast-action { min-height: 40px; }
}

/* ───────────────────────── 9. Chuyển động ───────────────────────── */
@keyframes spin { to { transform: rotate(360deg); } }
@keyframes fade-in { from { opacity: 0; } }
@keyframes modal-in { from { opacity: 0; transform: translateY(8px) scale(0.98); } }
@keyframes sheet-in { from { transform: translateY(24px); opacity: 0; } }
@keyframes toast-in { from { opacity: 0; transform: translateY(-8px); } }
@keyframes bubble {
  0%, 60%, 100% { background-color: transparent; border-color: var(--line-strong); }
  30% { background-color: var(--pencil); border-color: var(--pencil); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important; animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important; scroll-behavior: auto !important;
  }
  .sync[data-sync="saving"] .icon, .side-sync[data-sync="saving"] .icon { animation: none; }
  .loading-dots i { animation: none; background-color: var(--line); }
}