:root {
  color-scheme: dark;
  --bg: #000000;
  --bg-elevated: #0d0d0f;
  --panel: rgba(255, 255, 255, .045);
  --panel-strong: rgba(255, 255, 255, .075);
  --line: rgba(255, 255, 255, .085);
  --line-soft: rgba(255, 255, 255, .055);
  --muted: #98989f;
  --muted-2: #c7c7cc;
  --text: #f5f5f7;
  --accent: #0a84ff;
  --accent-strong: #3d9bff;
  --accent-soft: rgba(10, 132, 255, .16);
  --green: #30d158;
  --green-soft: rgba(48, 209, 88, .14);
  --amber: #ffd60a;
  --amber-soft: rgba(255, 214, 10, .12);
  --danger: #ff453a;
  --danger-soft: rgba(255, 69, 58, .14);
  --purple: #bf5af2;
  --purple-soft: rgba(191, 90, 242, .14);
  --radius-lg: 26px;
  --radius-md: 18px;
  --radius-sm: 13px;
  --shadow: 0 1px 0 rgba(255, 255, 255, .04) inset, 0 24px 70px rgba(0, 0, 0, .34);
}

* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; background: var(--bg); color: var(--text); font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "PingFang SC", "Microsoft YaHei", sans-serif; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
button, select, textarea, input { font: inherit; }
button { cursor: pointer; }
.hidden { display: none !important; }

.tc-topbar {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 34px;
  border-bottom: 1px solid var(--line-soft);
  background: rgba(0, 0, 0, .72);
  backdrop-filter: saturate(180%) blur(28px);
  -webkit-backdrop-filter: saturate(180%) blur(28px);
  position: sticky;
  top: 0;
  z-index: 5;
}
.tc-brand { color: var(--text); text-decoration: none; display: flex; align-items: center; gap: 12px; font-weight: 700; font-size: 18px; letter-spacing: -.02em; }
.tc-brand .brand-mark {
  width: 34px; height: 34px; display: grid; place-items: center; border-radius: 10px;
  background: linear-gradient(135deg, #0a84ff, #4da3ff);
  color: #fff; font-weight: 800; font-size: 17px;
  box-shadow: 0 8px 24px rgba(10, 132, 255, .28);
}
.tc-brand small {
  color: var(--muted); font-size: 12px; font-weight: 600;
  border: 1px solid var(--line-soft); padding: 4px 9px; border-radius: 999px; background: var(--panel);
}
.tc-top-actions { display: flex; align-items: center; gap: 10px; }

.tc-layout { min-height: calc(100vh - 72px); display: grid; grid-template-columns: 248px minmax(0, 1fr); }
.tc-nav {
  border-right: 1px solid var(--line-soft);
  background: rgba(10, 10, 12, .64);
  padding: 22px 14px;
  display: flex; flex-direction: column; gap: 6px;
}
.tc-nav-item {
  border: 0; border-radius: 14px; padding: 12px 15px; color: var(--muted);
  background: transparent; text-align: left; font-size: 14px; font-weight: 560;
  transition: background .18s ease, color .18s ease, transform .18s ease;
}
.tc-nav-item:hover { background: rgba(255, 255, 255, .06); color: var(--text); }
.tc-nav-item.active { background: var(--accent-soft); color: #dcecff; font-weight: 650; }

.tc-main { min-width: 0; padding: 46px 52px 64px; overflow: hidden; }
.tc-module { display: none; max-width: 980px; margin: 0 auto; }
.tc-module.active { display: block; animation: tcFade .28s ease both; }
.tc-module h1 { margin: 0 0 12px; font-size: 42px; font-weight: 760; letter-spacing: -.045em; line-height: 1.08; }
.tc-module .lead { color: var(--muted); line-height: 1.7; margin: 0 0 32px; max-width: 760px; font-size: 16px; letter-spacing: -.01em; }

.tc-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .052), rgba(255, 255, 255, .018)),
    rgba(255, 255, 255, .012);
  padding: 26px;
  margin-bottom: 18px;
  box-shadow: var(--shadow);
}
.tc-card h2 { margin: 0 0 14px; font-size: 21px; font-weight: 690; letter-spacing: -.025em; }
.tc-card-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 20px; margin-bottom: 12px; }
.tc-card-head h2 { margin-bottom: 0; }

.tc-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.tc-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; }
.tc-metric {
  border: 1px solid var(--line-soft); border-radius: var(--radius-md); padding: 17px 18px;
  background: rgba(255, 255, 255, .026);
}
.tc-metric strong { display: block; font-size: 27px; font-weight: 720; letter-spacing: -.03em; font-variant-numeric: tabular-nums; color: var(--text); margin-bottom: 6px; }
.tc-metric span { color: var(--muted); font-size: 12px; font-weight: 540; }

.tc-reference { font-size: clamp(24px, 2.6vw, 34px); line-height: 1.5; color: #fff; font-weight: 600; letter-spacing: -.025em; }
.tc-ipa { color: #b9bac1; font-size: 17px; line-height: 1.7; margin-top: 14px; letter-spacing: .015em; }
.tc-transcript {
  min-height: 108px; border: 1px solid rgba(10, 132, 255, .22); border-radius: var(--radius-md);
  background: rgba(0, 0, 0, .32); color: var(--text); padding: 18px 20px;
  font-size: 20px; line-height: 1.7; letter-spacing: -.01em;
}

.tc-diff { display: flex; flex-wrap: wrap; gap: 8px; align-items: flex-start; }
.tc-token { border-radius: 9px; padding: 6px 9px; line-height: 1.25; font-weight: 620; }
.tc-token.ok { background: var(--green-soft); color: #8ce99a; }
.tc-token.wrong { background: var(--danger-soft); color: #ffa8a2; border-bottom: 2px solid var(--danger); }
.tc-token.missing { background: var(--amber-soft); color: #ffe58a; border-bottom: 2px dashed var(--amber); }
.tc-token.extra { background: var(--purple-soft); color: #e3b7ff; border-bottom: 2px dotted var(--purple); }

.tc-feedback-list { display: grid; gap: 9px; padding: 0; margin: 0; }
.tc-feedback-list li {
  list-style: none; margin: 0; padding: 13px 15px; border-radius: 13px;
  background: rgba(255, 255, 255, .032); color: var(--muted-2); line-height: 1.55;
  border-left: 3px solid var(--muted);
}
.tc-feedback-list li.good { border-left-color: var(--green); color: #d8f6dd; }
.tc-feedback-list li.problem { border-left-color: var(--danger); color: #ffd8d5; }
.tc-feedback-list li.next { border-left-color: var(--accent); color: #dcecff; }

.tc-note { color: var(--muted); font-size: 13px; line-height: 1.7; margin-top: 12px; }
.tc-actions { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
.tc-button {
  border: 1px solid rgba(255, 255, 255, .12); background: rgba(255, 255, 255, .06);
  color: var(--text); border-radius: 999px; padding: 10px 17px; font-weight: 620; font-size: 14px;
  transition: background .18s ease, transform .18s ease, border-color .18s ease;
}
.tc-button:hover { background: rgba(255, 255, 255, .1); border-color: rgba(255, 255, 255, .18); }
.tc-button.primary {
  border: 0; background: var(--accent); color: #fff; font-weight: 700;
  box-shadow: 0 9px 26px rgba(10, 132, 255, .25);
}
.tc-button.primary:hover { background: var(--accent-strong); transform: translateY(-1px); }
.tc-button.danger { color: #ff9f99; border-color: rgba(255, 69, 58, .28); }
.tc-button.danger:hover { background: var(--danger-soft); }
.tc-button:disabled { opacity: .55; transform: none; cursor: default; }

.tc-segmented {
  display: inline-flex; padding: 4px; gap: 4px;
  background: rgba(255, 255, 255, .055); border: 1px solid var(--line-soft); border-radius: 999px;
}
.tc-segmented-item {
  border: 0; border-radius: 999px; padding: 9px 18px; color: var(--muted);
  background: transparent; font-weight: 620; font-size: 14px; transition: all .18s ease;
}
.tc-segmented-item.active { color: #fff; background: var(--accent); box-shadow: 0 6px 18px rgba(10, 132, 255, .22); }

.language-switch { display: inline-flex; padding: 3px; gap: 3px; background: rgba(255, 255, 255, .055); border: 1px solid var(--line-soft); border-radius: 999px; }
.language-button { border: 0; border-radius: 999px; padding: 7px 13px; color: var(--muted); background: transparent; font-weight: 650; transition: all .18s ease; }
.language-button.active { color: #fff; background: var(--accent); }

.tc-pinyin {
  display: flex; flex-wrap: wrap; align-items: flex-end; gap: 2px 0;
  margin-top: 16px; padding: 15px 14px 13px; border-radius: var(--radius-md);
  background: rgba(0, 0, 0, .24); border: 1px solid var(--line-soft);
}
.tc-pinyin-cell {
  display: inline-flex; flex-direction: column; align-items: center;
  min-width: 1.6em; padding: 0 1px;
}
.tc-pinyin-han { font-size: 24px; line-height: 1.12; color: #f5f5f7; font-weight: 590; letter-spacing: -.01em; }
.tc-pinyin-tone { font-size: 11px; line-height: 1.15; color: var(--muted); font-weight: 540; margin-top: 6px; white-space: nowrap; letter-spacing: .02em; }
.tc-pinyin-punct { font-size: 18px; color: var(--muted); font-weight: 500; align-self: flex-end; padding-bottom: 18px; }

.tc-highlight-output { white-space: pre-wrap; line-height: 1.9; font-size: 20px; color: #f5f5f7; }
.tc-accent-sentence { white-space: pre-wrap; line-height: 1.95; font-size: 20px; color: #f5f5f7; }
.tc-accent-hit {
  display: inline; background: var(--amber-soft); color: #ffe58a;
  border-bottom: 2px solid var(--amber); border-radius: 6px; padding: 2px 4px;
}
.tc-expression-hit {
  display: inline; background: var(--accent-soft); color: #dcecff;
  border-bottom: 2px solid var(--accent); border-radius: 6px; padding: 2px 4px;
}
.tc-live-hints { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 10px; }
.tc-live-chip {
  border: 1px solid rgba(255, 176, 32, .28); border-radius: 999px; padding: 5px 9px;
  background: rgba(255, 176, 32, .08); color: #ffe58a; font-size: 12px; line-height: 1.4;
}
.tc-input {
  width: 100%; min-height: 120px; resize: vertical; border: 1px solid rgba(255, 255, 255, .1);
  background: rgba(0, 0, 0, .26); color: var(--text); border-radius: 16px; padding: 16px 18px;
  line-height: 1.7; outline: 0; font-size: 17px; transition: border-color .18s ease, box-shadow .18s ease;
}
.tc-input:focus { border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }

.tc-custom-list { display: grid; gap: 10px; }
.tc-custom-row {
  display: flex; align-items: center; justify-content: space-between; gap: 18px;
  border: 1px solid var(--line-soft); border-radius: var(--radius-md);
  background: rgba(255, 255, 255, .028); padding: 14px 16px;
}
.tc-custom-main { min-width: 0; }
.tc-custom-text { color: #f5f5f7; font-size: 16px; line-height: 1.55; white-space: pre-wrap; }
.tc-custom-actions { display: flex; align-items: center; gap: 8px; flex: 0 0 auto; flex-wrap: wrap; justify-content: flex-end; }
.text-button.danger {
  border: 0; background: transparent; color: #ff9f99; padding: 8px 6px; font-weight: 620;
}

.tc-warmup { display: grid; gap: 10px; }
.tc-warmup-step {
  display: grid; grid-template-columns: 44px minmax(0, 1fr) auto; align-items: center; gap: 16px;
  border: 1px solid var(--line-soft); border-radius: var(--radius-md);
  background: rgba(255, 255, 255, .025); padding: 16px 18px;
}
.tc-warmup-index {
  width: 36px; height: 36px; border-radius: 12px; display: grid; place-items: center;
  color: #dcecff; background: var(--accent-soft); border: 1px solid rgba(10, 132, 255, .18);
  font-size: 12px; font-weight: 700; letter-spacing: .04em;
}
.tc-warmup-body { min-width: 0; }
.tc-warmup-body strong { display: block; color: #f5f5f7; font-size: 16px; margin-bottom: 5px; }
.tc-warmup-body p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.65; }
@media (max-width: 640px) {
  .tc-warmup-step { grid-template-columns: 38px minmax(0, 1fr); }
  .tc-warmup-step .tc-button { grid-column: 1 / -1; justify-self: start; }
}

.tc-route-card { padding: 0; overflow: hidden; }
.tc-feature-card {
  border-color: rgba(10, 132, 255, .30);
  background:
    linear-gradient(180deg, rgba(10, 132, 255, .07), rgba(10, 132, 255, .015)),
    rgba(255, 255, 255, .012);
  box-shadow: 0 1px 0 rgba(255, 255, 255, .04) inset, 0 24px 70px rgba(0, 0, 0, .34), 0 0 0 1px rgba(10, 132, 255, .04) inset;
}
.tc-route-card summary {
  list-style: none; cursor: pointer; display: flex; align-items: center; justify-content: space-between;
  gap: 20px; padding: 22px 26px; user-select: none;
}
.tc-route-card summary::-webkit-details-marker { display: none; }
.tc-route-card summary > div { display: grid; gap: 5px; min-width: 0; }
.tc-route-card summary span { font-size: 20px; font-weight: 690; color: var(--text); letter-spacing: -.02em; }
.tc-route-card summary small { color: var(--muted); font-size: 13px; line-height: 1.55; }
.tc-route-card summary::after {
  content: ''; flex: 0 0 auto; width: 8px; height: 8px;
  border-right: 2px solid var(--muted); border-bottom: 2px solid var(--muted);
  transform: rotate(45deg) translateY(-2px); transition: transform .2s ease;
}
.tc-route-card[open] summary::after { transform: rotate(225deg) translateY(-1px); }

.tc-plan-toolbar { display: flex; gap: 9px; flex-wrap: wrap; padding: 20px 26px 0; }
.tc-plan-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(270px, 1fr)); gap: 14px; padding: 20px 26px 26px; }
.tc-plan-day {
  border: 1px solid var(--line-soft); border-radius: var(--radius-md); padding: 19px;
  background: rgba(255, 255, 255, .028);
  transition: border-color .18s ease, background .18s ease, transform .18s ease;
}
.tc-plan-day:hover { border-color: rgba(255, 255, 255, .14); background: rgba(255, 255, 255, .045); transform: translateY(-1px); }
.tc-plan-day-head { display: flex; align-items: center; gap: 10px; margin-bottom: 15px; }
.tc-plan-day-head span {
  color: #dcecff; font-size: 11px; font-weight: 740; letter-spacing: .04em;
  border: 1px solid rgba(10, 132, 255, .28); padding: 4px 8px; border-radius: 999px; background: var(--accent-soft);
}
.tc-plan-day-head strong { font-size: 16px; font-weight: 660; color: var(--text); letter-spacing: -.01em; }

.tc-song-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap; padding: 20px 26px 0; }
.tc-song-list { display: grid; gap: 11px; padding: 18px 26px 26px; }
.tc-song-item {
  display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 20px; align-items: start;
  border: 1px solid var(--line-soft); border-radius: var(--radius-md); padding: 20px;
  background: rgba(255, 255, 255, .024);
}
.tc-song-main { min-width: 0; }

@keyframes tcFade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 820px) {
  .tc-layout { display: block; }
  .tc-nav { flex-direction: row; overflow-x: auto; padding: 12px; border-right: 0; border-bottom: 1px solid var(--line-soft); }
  .tc-nav-item { flex: 0 0 auto; }
  .tc-main { padding: 28px 18px 56px; }
  .tc-module h1 { font-size: 34px; }
  .tc-topbar { padding: 0 18px; }
}
@media (max-width: 620px) {
  .tc-plan-grid { grid-template-columns: 1fr; }
  .tc-song-item { grid-template-columns: 1fr; }
  .tc-card { padding: 20px; }
}


/* Apple-style overrides for shared controls loaded from web/styles.css */
.status-pill { color: var(--muted); font-size: 13px; font-weight: 560; }
.status-pill::before { display: none; }
.ghost-button, .secondary-button {
  border: 1px solid rgba(255, 255, 255, .12); background: rgba(255, 255, 255, .06);
  color: var(--text); border-radius: 999px; padding: 9px 15px; font-weight: 620;
  transition: background .18s ease, border-color .18s ease, color .18s ease;
}
.ghost-button:hover, .secondary-button:hover { background: rgba(255, 255, 255, .1); border-color: rgba(255, 255, 255, .18); }
.primary-button { border-radius: 999px; background: var(--accent); color: #fff; font-weight: 700; box-shadow: 0 9px 26px rgba(10, 132, 255, .25); }
.primary-button:hover { background: var(--accent-strong); }
.text-button { color: var(--muted); padding: 11px; }
.text-button.danger { color: #ff9f99; margin-right: auto; }

.modal { width: min(640px, calc(100vw - 32px)); border: 1px solid rgba(255, 255, 255, .1); border-radius: 24px; padding: 0; background: #0c0c0f; color: var(--text); box-shadow: 0 32px 110px rgba(0, 0, 0, .7); }
.modal::backdrop { background: rgba(0, 0, 0, .8); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); }
.modal-card { padding: 30px; }
.modal-heading { display: flex; align-items: flex-start; justify-content: space-between; margin-bottom: 24px; }
.modal-heading h2 { margin: 6px 0 0; font-size: 30px; letter-spacing: -.04em; }
.eyebrow { color: var(--accent); font-size: 12px; font-weight: 750; letter-spacing: .02em; }
.close-button { color: var(--muted); font-size: 28px; transition: color .16s ease; }
.close-button:hover { color: var(--text); }
.settings-card { max-height: min(860px, 90vh); overflow: auto; }
.settings-card fieldset { border-color: rgba(255, 255, 255, .09); border-radius: 18px; background: rgba(255, 255, 255, .02); }
.settings-card legend { color: var(--text); font-weight: 680; }
.settings-card input { border-color: rgba(255, 255, 255, .1); background: rgba(0, 0, 0, .24); border-radius: 12px; color: var(--text); }
.settings-card input:focus { border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
.settings-warning { color: #f3d58a; background: rgba(255, 214, 10, .07); border: 1px solid rgba(255, 214, 10, .2); border-radius: 13px; }
.settings-message { color: var(--green); }



/* English pronunciation course */
.tc-course-section { margin-bottom: 46px; }
.tc-course-head { margin-bottom: 20px; }
.tc-course-kicker {
  display: inline-flex; color: #7db7ff; font-size: 12px; font-weight: 760;
  letter-spacing: .09em; text-transform: uppercase; margin-bottom: 8px;
}
.tc-course-head h2 {
  margin: 0 0 8px; font-size: 31px; font-weight: 740; letter-spacing: -.035em; color: #f5f5f7;
}
.tc-course-head p { margin: 0; max-width: 680px; color: var(--muted); font-size: 15px; line-height: 1.7; }

.tc-course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }
.tc-course-card {
  display: flex; flex-direction: column; gap: 16px;
  border: 1px solid var(--line); border-radius: 24px; padding: 22px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .052), rgba(255, 255, 255, .014)),
    rgba(255, 255, 255, .014);
  box-shadow: 0 1px 0 rgba(255, 255, 255, .04) inset, 0 22px 64px rgba(0, 0, 0, .32);
  transition: border-color .2s ease, transform .2s ease, box-shadow .2s ease;
}
.tc-course-card:hover { border-color: rgba(255, 255, 255, .15); transform: translateY(-2px); box-shadow: 0 28px 80px rgba(0, 0, 0, .38); }
.tc-course-card-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; }
.tc-course-card-head h3 { margin: 0 0 6px; font-size: 17px; font-weight: 680; letter-spacing: -.015em; color: #f5f5f7; }
.tc-course-card-head p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.6; }
.tc-course-play {
  flex: 0 0 auto; width: 40px; height: 40px; border-radius: 50%; border: 0;
  background: var(--accent); color: #fff; font-size: 15px; font-weight: 800;
  display: grid; place-items: center; box-shadow: 0 9px 26px rgba(10, 132, 255, .26);
  transition: background .18s ease, transform .18s ease;
}
.tc-course-play:hover { background: var(--accent-strong); transform: scale(1.05); }
.tc-course-play:disabled { opacity: .6; transform: none; }
.tc-course-example { color: #f5f5f7; font-size: 23px; line-height: 1.45; font-weight: 630; letter-spacing: -.018em; }
.tc-course-focus { display: flex; flex-wrap: wrap; gap: 7px; margin-top: auto; }
.tc-course-focus span {
  color: #dcecff; font-size: 12px; line-height: 1.45; border: 1px solid rgba(10, 132, 255, .2);
  background: rgba(10, 132, 255, .08); border-radius: 999px; padding: 5px 9px;
}
@media (max-width: 620px) {
  .tc-course-grid { grid-template-columns: 1fr; }
  .tc-course-head h2 { font-size: 26px; }
}


/* =========================================================
   Apple-style visual refresh for the full training center
   ========================================================= */
:root {
  --bg: #050507;
  --bg-elevated: #0b0b0e;
  --panel: rgba(255, 255, 255, .052);
  --panel-strong: rgba(255, 255, 255, .082);
  --line: rgba(255, 255, 255, .095);
  --line-soft: rgba(255, 255, 255, .06);
  --muted: #9b9ba3;
  --muted-2: #c9c9cf;
  --text: #f5f5f7;
  --accent: #0a84ff;
  --accent-strong: #4da3ff;
  --accent-soft: rgba(10, 132, 255, .16);
  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 14px;
  --shadow: 0 1px 0 rgba(255, 255, 255, .05) inset, 0 30px 90px rgba(0, 0, 0, .42);
}

html, body {
  background: var(--bg);
  color: var(--text);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(900px 520px at 78% -8%, rgba(10, 132, 255, .16), transparent 62%),
    radial-gradient(720px 480px at -8% 42%, rgba(191, 90, 242, .09), transparent 60%),
    radial-gradient(820px 560px at 52% 108%, rgba(48, 209, 88, .07), transparent 62%),
    #050507;
}

.tc-topbar {
  min-height: 78px;
  padding: 0 38px;
  background: rgba(8, 8, 11, .66);
  border-bottom: 1px solid rgba(255, 255, 255, .065);
  backdrop-filter: saturate(190%) blur(30px);
  -webkit-backdrop-filter: saturate(190%) blur(30px);
}

.tc-brand { gap: 13px; font-size: 19px; }
.tc-brand .brand-mark {
  width: 38px; height: 38px; border-radius: 12px;
  background: linear-gradient(135deg, #0a84ff 0%, #5ac8fa 100%);
  box-shadow: 0 12px 34px rgba(10, 132, 255, .32), 0 1px 0 rgba(255, 255, 255, .26) inset;
}
.tc-brand small {
  color: var(--muted); font-size: 11px; font-weight: 650;
  border: 1px solid rgba(255, 255, 255, .09); padding: 5px 10px; border-radius: 999px;
  background: rgba(255, 255, 255, .04); letter-spacing: .02em;
}
.tc-top-actions { gap: 11px; }

.tc-layout {
  max-width: 1520px;
  margin: 0 auto;
  grid-template-columns: 286px minmax(0, 1fr);
}

.tc-nav {
  position: sticky;
  top: 78px;
  align-self: start;
  height: calc(100vh - 78px);
  overflow: auto;
  padding: 30px 18px;
  gap: 9px;
  border-right: 1px solid rgba(255, 255, 255, .06);
  background: linear-gradient(180deg, rgba(14, 14, 18, .78), rgba(8, 8, 11, .88));
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
}
.tc-nav::before {
  content: "训练模块";
  display: block;
  padding: 0 15px 14px;
  color: #6f6f78;
  font-size: 11px;
  font-weight: 750;
  letter-spacing: .14em;
  text-transform: uppercase;
}
.tc-nav-item {
  display: flex;
  align-items: center;
  gap: 11px;
  border-radius: 16px;
  padding: 14px 16px;
  color: #9b9ba3;
  font-size: 14px;
  font-weight: 580;
  transition: background .2s ease, color .2s ease, box-shadow .2s ease, transform .2s ease;
}
.tc-nav-item::before {
  content: "";
  width: 8px; height: 8px; flex: 0 0 auto; border-radius: 50%;
  background: currentColor; opacity: .38;
  box-shadow: 0 0 0 0 transparent;
  transition: opacity .2s ease, box-shadow .2s ease;
}
.tc-nav-item:hover {
  background: rgba(255, 255, 255, .065);
  color: #f5f5f7;
  transform: translateX(2px);
}
.tc-nav-item.active {
  background: linear-gradient(135deg, rgba(10, 132, 255, .20), rgba(10, 132, 255, .07));
  color: #dcecff;
  font-weight: 650;
  box-shadow: 0 1px 0 rgba(255, 255, 255, .08) inset, 0 14px 40px rgba(10, 132, 255, .10);
}
.tc-nav-item.active::before {
  background: #4da3ff;
  opacity: 1;
  box-shadow: 0 0 0 5px rgba(77, 163, 255, .14);
}

.tc-main {
  padding: 58px 62px 96px;
  background:
    radial-gradient(1000px 480px at 96% -4%, rgba(255, 255, 255, .045), transparent 62%),
    radial-gradient(720px 480px at -6% 34%, rgba(10, 132, 255, .05), transparent 58%);
}
.tc-module { max-width: 1180px; }
.tc-module h1 {
  margin: 0 0 14px;
  font-size: clamp(40px, 4.5vw, 56px);
  font-weight: 770;
  letter-spacing: -.05em;
  line-height: 1.05;
}
.tc-module .lead {
  margin-bottom: 34px;
  color: #a1a1a9;
  font-size: 17px;
  line-height: 1.75;
}

.tc-card {
  border-radius: var(--radius-lg);
  border-color: rgba(255, 255, 255, .095);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .055), rgba(255, 255, 255, .016)),
    rgba(255, 255, 255, .012);
  box-shadow: var(--shadow);
}
.tc-button,
.ghost-button,
.secondary-button {
  border-radius: 999px;
  padding: 10px 17px;
}
.primary-button { box-shadow: 0 12px 34px rgba(10, 132, 255, .30); }

/* Course hero */
.tc-course-hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 34px;
  overflow: hidden;
  margin-bottom: 58px;
  padding: 40px 42px;
  border: 1px solid rgba(255, 255, 255, .10);
  border-radius: 34px;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, .075), rgba(255, 255, 255, .02) 48%),
    rgba(255, 255, 255, .012);
  box-shadow: 0 1px 0 rgba(255, 255, 255, .07) inset, 0 38px 110px rgba(0, 0, 0, .42);
}
.tc-course-hero::after {
  content: "";
  position: absolute;
  right: -80px; top: -90px;
  width: 360px; height: 360px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(10, 132, 255, .20), transparent 66%);
  pointer-events: none;
}
.tc-course-hero-copy { position: relative; z-index: 1; min-width: 0; }
.tc-course-hero-copy h1 { margin: 6px 0 14px; }
.tc-course-hero-copy p { max-width: 720px; margin: 0; color: #a6a6ae; font-size: 16px; line-height: 1.8; }
.tc-course-hero-stats {
  position: relative; z-index: 1;
  display: flex; gap: 12px; flex-wrap: wrap; justify-content: flex-end;
}
.tc-course-hero-stats div {
  min-width: 112px;
  padding: 16px 18px;
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: 20px;
  background: rgba(0, 0, 0, .22);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.tc-course-hero-stats strong {
  display: block; margin-bottom: 6px;
  font-size: 25px; font-weight: 740; letter-spacing: -.04em; color: #fff;
  font-variant-numeric: tabular-nums;
}
.tc-course-hero-stats span { color: #92929b; font-size: 12px; font-weight: 620; }


/* Section headings */
.tc-course-section { margin-bottom: 54px; }
.tc-course-head {
  display: flex; align-items: flex-end; justify-content: space-between; gap: 24px;
  margin-bottom: 22px;
}
.tc-course-head-copy { min-width: 0; }
.tc-course-kicker {
  display: inline-flex; align-items: center; gap: 9px;
  color: #7db7ff; font-size: 11px; font-weight: 770;
  letter-spacing: .13em; text-transform: uppercase; margin-bottom: 9px;
}
.tc-course-kicker::before {
  content: ""; width: 26px; height: 1px;
  background: currentColor; opacity: .55;
}
.tc-course-head h2 {
  margin: 0 0 8px; font-size: 34px; font-weight: 750; letter-spacing: -.04em; color: #fff;
}
.tc-course-head p { margin: 0; max-width: 720px; color: #a0a0a8; font-size: 15px; line-height: 1.75; }
.tc-course-count {
  flex: 0 0 auto; color: #d4d4da; font-size: 12px; font-weight: 660;
  border: 1px solid rgba(255, 255, 255, .10); background: rgba(255, 255, 255, .045);
  padding: 8px 13px; border-radius: 999px; letter-spacing: .01em;
}
.tc-course-head-actions { flex: 0 0 auto; display: flex; align-items: center; gap: 10px; }
.tc-course-toggle {
  display: inline-flex; align-items: center; gap: 8px; border: 1px solid rgba(255, 255, 255, .11);
  background: rgba(255, 255, 255, .05); color: #d8d8de; font-size: 13px; font-weight: 680;
  padding: 8px 13px; border-radius: 999px; cursor: pointer; transition: background .18s ease, border-color .18s ease, color .18s ease;
}
.tc-course-toggle:hover { background: rgba(255, 255, 255, .10); color: #fff; border-color: rgba(255, 255, 255, .18); }
.tc-course-chevron { font-size: 13px; line-height: 1; transition: transform .18s ease; }
.tc-course-section.tc-course-collapsed .tc-course-grid { display: none; }
.tc-course-section.tc-course-collapsed .tc-course-chevron { transform: rotate(-90deg); }
.tc-course-section.tc-course-collapsed .tc-course-head { margin-bottom: 0; }


/* Section accent colors */
[data-course-section="phonemes"] {
  --course-accent: #4da3ff;
  --course-soft: rgba(77, 163, 255, .15);
  --course-line: rgba(77, 163, 255, .30);
}
[data-course-section="rhythm"] {
  --course-accent: #bf5af2;
  --course-soft: rgba(191, 90, 242, .15);
  --course-line: rgba(191, 90, 242, .30);
}
[data-course-section="prosody"] {
  --course-accent: #30d158;
  --course-soft: rgba(48, 209, 88, .15);
  --course-line: rgba(48, 209, 88, .30);
}
[data-course-section="process-simulation"] { --course-accent: #64d2ff; --course-soft: rgba(100, 210, 255, .15); --course-line: rgba(100, 210, 255, .30); }
[data-course-section="phonemes"] .tc-course-kicker { color: #8cc0ff; }
[data-course-section="rhythm"] .tc-course-kicker { color: #dfa2ff; }
[data-course-section="prosody"] .tc-course-kicker { color: #8ce99a; }
[data-course-section="process-simulation"] .tc-course-kicker { color: #8ee4ff; }
[data-course-section="industry"] { --course-accent: #ffb340; --course-soft: rgba(255, 179, 64, .15); --course-line: rgba(255, 179, 64, .30); }
[data-course-section="products"] { --course-accent: #ff8a66; --course-soft: rgba(255, 138, 102, .15); --course-line: rgba(255, 138, 102, .30); }
[data-course-section="chemicals"] { --course-accent: #4dd8d0; --course-soft: rgba(77, 216, 208, .15); --course-line: rgba(77, 216, 208, .30); }
[data-course-section="processes"] { --course-accent: #f5c34d; --course-soft: rgba(245, 195, 77, .15); --course-line: rgba(245, 195, 77, .30); }
[data-course-section="crude"] { --course-accent: #c99a6b; --course-soft: rgba(201, 154, 107, .15); --course-line: rgba(201, 154, 107, .30); }
[data-course-section="romeo"] { --course-accent: #7aa2f7; --course-soft: rgba(122, 162, 247, .15); --course-line: rgba(122, 162, 247, .30); }
[data-course-section="simulation-tools"] { --course-accent: #9d7bff; --course-soft: rgba(157, 123, 255, .15); --course-line: rgba(157, 123, 255, .30); }
[data-course-section="aspen-eo"] { --course-accent: #57c7ff; --course-soft: rgba(87, 199, 255, .15); --course-line: rgba(87, 199, 255, .30); }
[data-course-section="equipment-models"] { --course-accent: #ff7aa8; --course-soft: rgba(255, 122, 168, .15); --course-line: rgba(255, 122, 168, .30); }
[data-course-section="industry"] .tc-course-kicker { color: #ffc46b; }
[data-course-section="products"] .tc-course-kicker { color: #ff9a7a; }
[data-course-section="chemicals"] .tc-course-kicker { color: #6fe3dc; }
[data-course-section="processes"] .tc-course-kicker { color: #f7d171; }
[data-course-section="crude"] .tc-course-kicker { color: #d7a77a; }
[data-course-section="romeo"] .tc-course-kicker { color: #93b5ff; }
[data-course-section="simulation-tools"] .tc-course-kicker { color: #b394ff; }
[data-course-section="aspen-eo"] .tc-course-kicker { color: #77d3ff; }
[data-course-section="equipment-models"] .tc-course-kicker { color: #ff8fba; }


.tc-course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}
.tc-course-card {
  position: relative;
  overflow: hidden;
  gap: 17px;
  border: 1px solid rgba(255, 255, 255, .10);
  border-radius: 28px;
  padding: 25px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .058), rgba(255, 255, 255, .014)),
    rgba(255, 255, 255, .012);
  box-shadow: 0 1px 0 rgba(255, 255, 255, .05) inset, 0 24px 72px rgba(0, 0, 0, .34);
  transition: border-color .24s ease, transform .24s ease, box-shadow .24s ease;
}
.tc-course-card::after {
  content: "";
  position: absolute; inset: 0; border-radius: inherit; pointer-events: none;
  box-shadow: 0 0 0 1px var(--course-soft) inset;
  opacity: 0;
  transition: opacity .24s ease;
}
.tc-course-card:hover {
  border-color: var(--course-line);
  transform: translateY(-4px);
  box-shadow: 0 30px 88px rgba(0, 0, 0, .42), 0 0 60px var(--course-soft);
}
.tc-course-card:hover::after { opacity: 1; }
.tc-course-card-glow {
  position: absolute;
  top: -110px; right: -90px;
  width: 260px; height: 260px; border-radius: 50%;
  background: radial-gradient(circle, var(--course-soft), transparent 68%);
  pointer-events: none;
}
.tc-course-card-head {
  position: relative; z-index: 1;
  align-items: flex-start; justify-content: space-between; gap: 16px;
}
.tc-course-card-title { display: flex; align-items: flex-start; gap: 12px; min-width: 0; }
.tc-course-card-index {
  flex: 0 0 auto; width: 32px; height: 32px; border-radius: 10px;
  display: grid; place-items: center;
  color: var(--course-accent); background: var(--course-soft);
  border: 1px solid var(--course-line); font-size: 11px; font-weight: 770;
  letter-spacing: .02em; font-variant-numeric: tabular-nums;
}
.tc-course-card-title h3 { margin: 0 0 6px; font-size: 17px; font-weight: 700; letter-spacing: -.018em; color: #fff; }
.tc-course-card-title p { margin: 0; color: #a2a2aa; font-size: 13px; line-height: 1.62; }
.tc-course-play {
  position: relative; z-index: 1;
  flex: 0 0 auto; width: 42px; height: 42px; border-radius: 50%; border: 0;
  background: var(--course-accent); color: #fff; font-size: 15px; font-weight: 800;
  display: grid; place-items: center;
  box-shadow: 0 10px 30px color-mix(in srgb, var(--course-accent) 34%, transparent);
  transition: background .18s ease, transform .18s ease, box-shadow .18s ease;
}
.tc-course-play:hover { transform: scale(1.06); filter: brightness(1.06); }
.tc-course-play:disabled { opacity: .55; transform: none; }
.tc-course-example {
  position: relative; z-index: 1;
  color: #fff; font-size: 25px; line-height: 1.42; font-weight: 630; letter-spacing: -.022em;
}
.tc-course-translation {
  position: relative; z-index: 1;
  color: #aeb8c8; font-size: 13px; line-height: 1.55; margin-top: 8px; font-weight: 500;
}
.tc-course-focus {
  position: relative; z-index: 1;
  display: flex; flex-wrap: wrap; gap: 7px; margin-top: auto;
}
.tc-course-focus span {
  color: #f4f4f7; font-size: 11px; line-height: 1.45;
  border: 1px solid var(--course-line); background: var(--course-soft);
  border-radius: 999px; padding: 5px 10px; font-weight: 590;
}

@media (max-width: 900px) {
  .tc-layout { grid-template-columns: 230px minmax(0, 1fr); }
  .tc-main { padding: 42px 34px 72px; }
  .tc-course-hero { grid-template-columns: 1fr; align-items: start; padding: 32px 30px; }
  .tc-course-hero-stats { justify-content: flex-start; }
}
@media (max-width: 820px) {
  .tc-layout { display: block; }
  .tc-nav {
    position: static; height: auto; overflow-x: auto; padding: 12px;
    border-right: 0; border-bottom: 1px solid var(--line-soft);
    background: rgba(10, 10, 13, .86);
  }
  .tc-nav::before { display: none; }
  .tc-nav-item { flex: 0 0 auto; }
}
@media (max-width: 620px) {
  .tc-topbar { padding: 0 16px; }
  .tc-main { padding: 28px 18px 60px; }
  .tc-module h1 { font-size: 38px; }
  .tc-course-hero { padding: 28px 22px; border-radius: 26px; }
  .tc-course-hero-stats div { min-width: 96px; }
  .tc-course-head { align-items: flex-start; flex-direction: column; gap: 12px; }
  .tc-course-head h2 { font-size: 28px; }
  .tc-course-grid { grid-template-columns: 1fr; }
  .tc-course-card { padding: 22px; border-radius: 24px; }
  .tc-course-example { font-size: 23px; }
}


/* Course quick navigation / search */
.tc-main { overflow: visible; }
.tc-course-section { scroll-margin-top: 152px; }
.tc-course-toolbar {
  position: sticky;
  top: 78px;
  z-index: 4;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
  margin: -8px 0 38px;
  padding: 14px 15px;
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: 22px;
  background: rgba(10, 10, 13, .78);
  backdrop-filter: saturate(180%) blur(24px);
  -webkit-backdrop-filter: saturate(180%) blur(24px);
  box-shadow: 0 18px 50px rgba(0, 0, 0, .26);
}
.tc-course-toolbar-main {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: 1 1 520px;
  min-width: 0;
  flex-wrap: wrap;
}
.tc-course-filters {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 4px;
  padding: 4px;
  border: 1px solid rgba(255, 255, 255, .08);
  border-radius: 999px;
  background: rgba(0, 0, 0, .22);
}
.tc-course-filter {
  border: 0;
  border-radius: 999px;
  padding: 9px 15px;
  color: #a0a0a8;
  background: transparent;
  font-size: 13px;
  font-weight: 640;
  white-space: nowrap;
  transition: background .18s ease, color .18s ease, box-shadow .18s ease;
}
.tc-course-filter:hover { color: #fff; background: rgba(255, 255, 255, .07); }
.tc-course-filter.active {
  color: #fff;
  background: var(--accent);
  box-shadow: 0 8px 22px rgba(10, 132, 255, .26);
}
.tc-course-search {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  min-width: min(320px, 100%);
  flex: 1 1 260px;
  padding: 0 14px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, .10);
  border-radius: 999px;
  background: rgba(0, 0, 0, .24);
  color: #8f8f98;
  transition: border-color .18s ease, box-shadow .18s ease, background .18s ease;
}
.tc-course-search:focus-within {
  border-color: rgba(10, 132, 255, .55);
  background: rgba(10, 132, 255, .07);
  box-shadow: 0 0 0 4px rgba(10, 132, 255, .10);
}
.tc-course-search span {
  flex: 0 0 auto;
  font-size: 12px;
  font-weight: 720;
  letter-spacing: .04em;
  color: #7d7d86;
}
.tc-course-search input {
  width: 100%;
  min-width: 0;
  border: 0;
  outline: 0;
  background: transparent;
  color: #f5f5f7;
  font-size: 14px;
}
.tc-course-search input::placeholder { color: #74747d; }
.tc-course-result {
  flex: 0 0 auto;
  color: #92929b;
  font-size: 12px;
  font-weight: 620;
  padding: 8px 11px;
  border-radius: 999px;
  background: rgba(255, 255, 255, .045);
  white-space: nowrap;
}
.tc-course-filter[hidden] { display: none !important; }
.tc-course-filters[hidden] { display: none !important; }
.tc-course-speaking-context { margin-top: -6px; color: #b4b4bd; font-size: 12px; line-height: 1.65; }
.tc-course-speaking-context span { display: inline-block; margin-right: 8px; padding: 2px 7px; border-radius: 999px; color: var(--course-accent); background: var(--course-soft); font-size: 10px; font-weight: 750; }

/* Filtered Aspen vocabulary bank */
.tc-course-view-switch { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin: -8px 0 28px; }

.tc-course-view-switch button { display: flex; flex-direction: column; align-items: flex-start; gap: 4px; padding: 18px 20px; border: 1px solid rgba(255,255,255,.09); border-radius: 20px; color: #9999a2; background: rgba(255,255,255,.035); text-align: left; }
.tc-course-view-switch button:hover { border-color: rgba(100,210,255,.28); background: rgba(100,210,255,.055); }
.tc-course-view-switch button.active { border-color: rgba(100,210,255,.48); color: #fff; background: linear-gradient(135deg, rgba(10,132,255,.16), rgba(100,210,255,.08)); box-shadow: 0 16px 44px rgba(0,0,0,.20); }
.tc-course-view-switch strong { font-size: 16px; }
.tc-course-view-switch span { font-size: 12px; color: #8d8d96; }
.tc-professional-mode-switch { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin: -10px 0 22px; padding: 16px 18px; border: 1px solid rgba(100,210,255,.16); border-radius: 18px; background: rgba(100,210,255,.045); }
.tc-professional-mode-switch[hidden] { display: none !important; }
.tc-professional-mode-switch > div:first-child { display: flex; flex-direction: column; gap: 3px; }
.tc-professional-mode-switch span { color: #64d2ff; font-size: 11px; font-weight: 760; letter-spacing: .05em; }
.tc-professional-mode-switch strong { color: #c3c3cb; font-size: 13px; }
.tc-professional-mode-actions { display: inline-flex; flex: 0 0 auto; gap: 5px; padding: 4px; border: 1px solid rgba(255,255,255,.09); border-radius: 999px; background: rgba(0,0,0,.24); }
.tc-professional-mode-actions button { min-width: 104px; padding: 9px 16px; border: 0; border-radius: 999px; color: #92929b; background: transparent; font-size: 13px; font-weight: 700; }
.tc-professional-mode-actions button.active { color: #fff; background: var(--accent); box-shadow: 0 7px 20px rgba(10,132,255,.24); }
.tc-aspen-bank { margin: 0 0 54px; padding: 28px; border: 1px solid rgba(100, 210, 255, .18); border-radius: 28px; background: linear-gradient(145deg, rgba(100, 210, 255, .08), rgba(18, 18, 22, .86) 34%); }
.tc-aspen-bank[hidden], .tc-course-section[hidden] { display: none !important; }
.tc-aspen-bank-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; margin-bottom: 20px; }
.tc-aspen-bank-head h2 { margin: 5px 0 7px; color: #fff; font-size: 30px; letter-spacing: -.025em; }
.tc-aspen-bank-head p { margin: 0; color: #9f9fa8; font-size: 14px; line-height: 1.65; }
.tc-aspen-bank-head > strong { flex: 0 0 auto; padding: 8px 12px; border-radius: 999px; color: #9be8ff; background: rgba(100, 210, 255, .10); font-size: 12px; }
.tc-aspen-controls { display: flex; align-items: end; gap: 12px; margin-bottom: 18px; padding: 14px; border: 1px solid rgba(255,255,255,.07); border-radius: 16px; background: rgba(255,255,255,.025); }
.tc-aspen-controls label { display: flex; flex-direction: column; gap: 6px; }
.tc-aspen-controls label > span { color: #777782; font-size: 10px; font-weight: 760; letter-spacing: .06em; }
.tc-aspen-controls select { min-width: 220px; height: 38px; padding: 0 34px 0 12px; border: 1px solid rgba(100,210,255,.22); border-radius: 11px; color: #e9e9ed; background: #15171b; font-size: 12px; }
.tc-aspen-controls label:nth-child(2) select { min-width: 120px; }
.tc-aspen-control-hint { margin-left: auto; padding-bottom: 10px; color: #6f6f79; font-size: 11px; }
.tc-aspen-term > small { display: block; margin-bottom: 5px; color: #64d2ff; font-size: 10px; font-weight: 760; letter-spacing: .04em; }
.tc-aspen-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(310px, 1fr)); gap: 16px; }
.tc-word-card { display: flex; min-width: 0; flex-direction: column; padding: 22px; border: 1px solid rgba(255,255,255,.10); border-radius: 22px; background: linear-gradient(155deg, rgba(255,255,255,.075), rgba(255,255,255,.018)); box-shadow: 0 1px 0 rgba(255,255,255,.06) inset, 0 18px 44px rgba(0,0,0,.16); transition: transform .2s ease, border-color .2s ease, box-shadow .2s ease; }
.tc-word-card:hover { transform: translateY(-3px); border-color: rgba(100,210,255,.38); box-shadow: 0 22px 56px rgba(0,0,0,.28), 0 0 0 1px rgba(100,210,255,.08) inset; }
.tc-word-card-top { display: flex; align-items: center; justify-content: space-between; gap: 14px; }
.tc-word-card-top > span { color: #7ccfff; font-size: 10px; font-weight: 760; letter-spacing: .08em; text-transform: uppercase; }
.tc-word-card h3 { margin: 18px 0 4px; color: #fff; font-size: 21px; line-height: 1.18; letter-spacing: -.025em; overflow-wrap: anywhere; }
.tc-word-meaning { min-height: 20px; margin: 0; color: #8edcff; font-size: 13px; line-height: 1.5; }
.tc-word-context { min-height: 42px; margin: 14px 0 16px; color: #a1a1aa; font-size: 12px; line-height: 1.65; }
.tc-word-context > span { display: block; margin-bottom: 4px; color: #777782; font-size: 10px; font-weight: 750; letter-spacing: .08em; }
.tc-word-context p { margin: 0; }
.tc-word-example { margin-top: auto; padding: 14px; border: 1px solid rgba(255,255,255,.075); border-radius: 14px; background: rgba(0,0,0,.18); }
.tc-word-example > span { color: #777782; font-size: 10px; font-weight: 750; letter-spacing: .08em; }
.tc-word-example p { margin: 7px 0 6px; color: #f3f3f6; font-size: 13px; line-height: 1.58; }
.tc-word-example small { color: #9999a2; font-size: 12px; line-height: 1.5; }
.tc-word-audio, .tc-word-sentence { border: 1px solid rgba(100,210,255,.28); border-radius: 999px; color: #b8edff; background: rgba(100,210,255,.08); font-size: 11px; font-weight: 740; transition: background .18s ease, color .18s ease, transform .18s ease; }
.tc-word-audio { display: inline-flex; align-items: center; gap: 5px; padding: 7px 10px; }
.tc-word-audio i { color: inherit; font-style: normal; }
.tc-word-actions { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 8px; margin-top: 13px; }
.tc-word-sentence { display: flex; align-items: center; justify-content: space-between; width: 100%; padding: 10px 13px; text-align: left; }
.tc-word-shadow { border: 1px solid rgba(255,255,255,.13); border-radius: 999px; padding: 10px 12px; color: #d5d5dc; background: rgba(255,255,255,.045); font-size: 11px; font-weight: 740; }
.tc-word-shadow:hover { color: #fff; border-color: rgba(255,255,255,.3); background: rgba(255,255,255,.10); }
.tc-word-practice { margin-top: 12px; padding: 15px; border: 1px solid rgba(100,210,255,.20); border-radius: 15px; background: rgba(100,210,255,.055); }
.tc-word-practice[hidden] { display: none; }
.tc-word-practice-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.tc-word-practice-head span { color: #7ccfff; font-size: 10px; font-weight: 760; letter-spacing: .08em; }
.tc-word-practice-head strong { color: #fff; font-size: 12px; overflow-wrap: anywhere; text-align: right; }
.tc-word-practice > p { margin: 9px 0 12px; color: #e9e9ed; font-size: 13px; line-height: 1.55; }
.tc-word-practice-actions { display: flex; gap: 8px; }
.tc-word-practice-actions button { border: 1px solid rgba(255,255,255,.13); border-radius: 999px; padding: 8px 11px; color: #d8d8df; background: rgba(0,0,0,.14); font-size: 11px; font-weight: 730; }
.tc-word-practice-actions button.primary { color: #fff; border-color: #0a84ff; background: #0a84ff; }
.tc-word-transcript { min-height: 18px; margin-top: 11px; color: #a6a6af; font-size: 12px; line-height: 1.55; }
.tc-word-score { display: flex; align-items: center; flex-wrap: wrap; gap: 7px 10px; margin-top: 12px; padding-top: 12px; border-top: 1px solid rgba(255,255,255,.09); }
.tc-word-score strong { color: #8ee4ff; font-size: 24px; font-variant-numeric: tabular-nums; }
.tc-word-score span { color: #8e8e98; font-size: 11px; }
.tc-word-score p { flex-basis: 100%; margin: 0; color: #d4d4db; font-size: 12px; line-height: 1.5; }
.tc-word-assessment { margin-top: 8px; color: #7fe3a3; font-size: 11px; }
.tc-word-audio:hover, .tc-word-sentence:hover { color: #07141a; background: #64d2ff; transform: translateY(-1px); }
.tc-word-audio:disabled, .tc-word-sentence:disabled { opacity: .5; transform: none; }
.tc-aspen-more { display: block; margin: 20px auto 0; border: 1px solid rgba(100,210,255,.30); border-radius: 999px; padding: 10px 18px; color: #a6eaff; background: rgba(100,210,255,.08); font-size: 12px; font-weight: 700; }
.tc-aspen-pagination { display: flex; align-items: center; justify-content: center; gap: 14px; margin-top: 20px; }
.tc-aspen-pagination button { border: 1px solid rgba(100,210,255,.28); border-radius: 999px; padding: 9px 15px; color: #b8edff; background: rgba(100,210,255,.07); font-size: 12px; font-weight: 700; }
.tc-aspen-pagination button:disabled { opacity: .35; }
.tc-aspen-pagination span { min-width: 120px; color: #8f8f98; font-size: 12px; text-align: center; }
.tc-aspen-page-numbers { display: flex; align-items: center; gap: 5px; }
.tc-aspen-page-numbers button { min-width: 34px; padding: 8px 9px; }
.tc-aspen-page-numbers button.active { color: #07141a; border-color: #64d2ff; background: #64d2ff; }
.tc-aspen-page-numbers span { min-width: auto; padding: 0 2px; }
.tc-aspen-empty { grid-column: 1 / -1; padding: 28px; color: #85858e; text-align: center; }

@media (max-width: 900px) {
  .tc-course-toolbar { top: 76px; }
  .tc-course-view-switch { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 820px) {
  .tc-course-toolbar {
    position: static;
    margin: -4px 0 30px;
  }
  .tc-course-section { scroll-margin-top: 18px; }
}
@media (max-width: 620px) {
  .tc-aspen-controls { align-items: stretch; flex-direction: column; }
  .tc-aspen-controls select { width: 100%; min-width: 0; }
  .tc-aspen-control-hint { margin-left: 0; padding: 0; }
  .tc-aspen-pagination { flex-wrap: wrap; }
  .tc-course-toolbar-main { gap: 10px; }
  .tc-course-filters { width: 100%; overflow-x: auto; }
  .tc-course-filter { flex: 1 0 auto; }
  .tc-course-search { min-width: 100%; }
  .tc-course-result { width: 100%; text-align: center; }
  .tc-aspen-bank { padding: 22px 16px; }
  .tc-aspen-bank-head { flex-direction: column; gap: 10px; }
  .tc-aspen-list { grid-template-columns: 1fr; }
  .tc-word-card { padding: 19px; }
}


/* Free-expression topic inspiration */
.tc-topic-picker {
  margin-top: 16px;
  padding: 16px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-md);
  background: rgba(0, 0, 0, .18);
}
.tc-topic-picker-head {
  margin-bottom: 10px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 720;
  letter-spacing: .05em;
}
.tc-topic-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.tc-topic-chip {
  border: 1px solid rgba(255, 255, 255, .12);
  border-radius: 999px;
  padding: 8px 13px;
  color: var(--muted-2);
  background: rgba(255, 255, 255, .045);
  font-size: 13px;
  font-weight: 620;
  transition: background .18s ease, border-color .18s ease, color .18s ease, transform .18s ease;
}
.tc-topic-chip:hover {
  border-color: rgba(255, 255, 255, .22);
  background: rgba(255, 255, 255, .08);
  color: #fff;
}
.tc-topic-chip.active {
  border-color: var(--accent);
  color: #fff;
  background: var(--accent);
}
.tc-topic-chip.free.active {
  border-color: var(--green);
  background: var(--green);
  color: #04210d;
}


/* Advanced optional pronunciation settings */
.advanced-setting {
  margin: 0 0 16px;
  padding: 18px;
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: 18px;
  background: rgba(255, 255, 255, .02);
}
.advanced-setting summary {
  cursor: pointer;
  color: var(--text);
  font-weight: 680;
  font-size: 14px;
  letter-spacing: -.01em;
}
.advanced-setting summary:hover { color: #fff; }
.advanced-setting[open] summary { margin-bottom: 14px; }
.advanced-setting label {
  display: grid;
  gap: 6px;
  margin-top: 12px;
  color: var(--muted-2);
  font-size: 13px;
  font-weight: 620;
}
@media (max-width: 620px) {
  .tc-course-view-switch { grid-template-columns: 1fr; }
  .tc-professional-mode-switch { align-items: stretch; flex-direction: column; }
  .tc-professional-mode-actions { display: grid; grid-template-columns: 1fr 1fr; }
}