:root {
  --bg0: #0b1020;
  --bg1: #0f172a;
  --card: rgba(255, 255, 255, 0.06);
  --card2: rgba(255, 255, 255, 0.08);
  --stroke: rgba(255, 255, 255, 0.12);
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.62);
  --muted2: rgba(255, 255, 255, 0.45);
  --accent: #7c3aed;
  --accent2: #22d3ee;
  --shadow: 0 14px 40px rgba(0, 0, 0, 0.4);
  --radius: 16px;
  --radius2: 12px;
  --gap: 14px;
  --maxw: 1200px;
  color-scheme: dark light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei",
    "Noto Sans CJK SC", Arial, sans-serif;
  color: var(--text);
  background: radial-gradient(1400px 900px at 20% -10%, rgba(124, 58, 237, 0.35), transparent 55%),
    radial-gradient(900px 700px at 110% 10%, rgba(34, 211, 238, 0.25), transparent 45%),
    linear-gradient(180deg, var(--bg0), var(--bg1));
  padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.95em;
  padding: 1px 7px;
  border-radius: 9px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(0, 0, 0, 0.25);
  color: rgba(255, 255, 255, 0.86);
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(14px);
  background: rgba(10, 14, 28, 0.68);
  border-bottom: 1px solid var(--stroke);
}

.topbar__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 14px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand {
  display: grid;
  gap: 4px;
  min-width: 0;
}

.brand__title {
  font-weight: 750;
  letter-spacing: 0.2px;
  font-size: 18px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.brand__subtitle {
  font-size: 12px;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.topbar__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: flex-end;
}

.btn {
  appearance: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--stroke);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.10), rgba(255, 255, 255, 0.06));
  color: var(--text);
  padding: 9px 12px;
  border-radius: 10px;
  cursor: pointer;
  font-weight: 650;
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.22);
  transition: transform 120ms ease, border-color 120ms ease, background 120ms ease, opacity 120ms ease;
}

.btn:hover {
  transform: translateY(-1px);
  border-color: rgba(255, 255, 255, 0.22);
}

.btn:active {
  transform: translateY(0);
  opacity: 0.92;
}

.btn:disabled {
  cursor: not-allowed;
  opacity: 0.5;
  transform: none;
}

.btn--ghost {
  background: transparent;
}

.app {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 16px;
  display: grid;
  grid-template-columns: 1.6fr 0.9fr;
  gap: var(--gap);
  align-items: start;
}

.card {
  border: 1px solid var(--stroke);
  background: linear-gradient(180deg, var(--card), rgba(255, 255, 255, 0.03));
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.player {
  padding: 14px;
  display: grid;
  gap: 12px;
}

.player__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}

.player__title {
  font-size: 16px;
  font-weight: 750;
  letter-spacing: 0.2px;
}

.player__hint {
  font-size: 12px;
  color: var(--muted);
}

.player__stage {
  border-radius: calc(var(--radius) - 6px);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.10);
  background: radial-gradient(500px 300px at 20% 20%, rgba(124, 58, 237, 0.28), transparent 60%),
    radial-gradient(500px 300px at 80% 10%, rgba(34, 211, 238, 0.22), transparent 55%),
    rgba(0, 0, 0, 0.35);
}

.player__video {
  width: 100%;
  height: auto;
  display: block;
  aspect-ratio: 16 / 9;
  background: transparent;
}

.player__footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  color: var(--muted);
  font-size: 12px;
}

.status {
  color: var(--muted2);
}

.kbd-hint {
  display: flex;
  align-items: center;
  gap: 6px;
}

.kbd {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 2px 8px;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(0, 0, 0, 0.25);
  font-weight: 700;
  color: rgba(255, 255, 255, 0.82);
}

.playlist {
  padding: 14px;
  display: grid;
  gap: 12px;
}

.playlist__header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}

.playlist__title {
  font-weight: 750;
  letter-spacing: 0.2px;
}

.playlist__count {
  font-size: 12px;
  color: var(--muted);
}

.video-list {
  display: grid;
  gap: 10px;
}

.video-item {
  width: 100%;
  display: grid;
  grid-template-columns: 132px 1fr;
  gap: 12px;
  padding: 10px;
  text-align: left;
  border-radius: var(--radius2);
  border: 1px solid rgba(255, 255, 255, 0.10);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.06), rgba(255, 255, 255, 0.03));
  cursor: pointer;
  color: inherit;
  transition: border-color 120ms ease, transform 120ms ease, background 120ms ease;
}

.video-item:hover {
  transform: translateY(-1px);
  border-color: rgba(255, 255, 255, 0.20);
}

.video-item:active {
  transform: translateY(0);
}

.video-item:focus-visible {
  outline: 2px solid rgba(34, 211, 238, 0.7);
  outline-offset: 2px;
}

.video-item.is-active {
  border-color: rgba(124, 58, 237, 0.72);
  background: linear-gradient(180deg, rgba(124, 58, 237, 0.18), rgba(255, 255, 255, 0.03));
}

.thumb {
  position: relative;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.10);
  background: radial-gradient(220px 140px at 20% 20%, rgba(124, 58, 237, 0.35), transparent 62%),
    radial-gradient(220px 140px at 90% 30%, rgba(34, 211, 238, 0.26), transparent 60%),
    rgba(0, 0, 0, 0.35);
  aspect-ratio: 16 / 9;
}

.thumb__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(1.05) contrast(1.02);
}

.thumb::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 40%, rgba(0, 0, 0, 0.44));
  pointer-events: none;
}

.thumb__badge {
  position: absolute;
  top: 8px;
  left: 8px;
  z-index: 2;
  font-size: 12px;
  font-weight: 800;
  padding: 2px 8px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(0, 0, 0, 0.30);
}

.thumb__dur {
  position: absolute;
  right: 8px;
  bottom: 8px;
  z-index: 2;
  font-size: 12px;
  font-weight: 750;
  padding: 2px 8px;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(0, 0, 0, 0.32);
  color: rgba(255, 255, 255, 0.90);
}

.thumb__play {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  z-index: 1;
  pointer-events: none;
}

.thumb__play > span {
  width: 44px;
  height: 44px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.20);
  background: rgba(0, 0, 0, 0.26);
  display: grid;
  place-items: center;
  backdrop-filter: blur(10px);
  box-shadow: 0 10px 22px rgba(0, 0, 0, 0.30);
}

.thumb__play > span::before {
  content: "";
  display: block;
  width: 0;
  height: 0;
  border-left: 11px solid rgba(255, 255, 255, 0.88);
  border-top: 7px solid transparent;
  border-bottom: 7px solid transparent;
  transform: translateX(1px);
}

.meta {
  display: grid;
  gap: 6px;
  align-content: center;
  min-width: 0;
}

.meta__title {
  font-weight: 750;
  letter-spacing: 0.2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.meta__desc {
  font-size: 12px;
  color: var(--muted);
  line-height: 1.35;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

@media (max-width: 980px) {
  .app {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .topbar__inner {
    padding: 12px 12px;
  }
  .app {
    padding: 12px;
  }
  .video-item {
    grid-template-columns: 120px 1fr;
  }
  .brand__subtitle {
    display: none;
  }
  .kbd-hint {
    display: none;
  }
}

/* Home page (index.html) */
.home {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 18px 16px;
}

.home-intro {
  padding: 16px;
}

.home-intro__line {
  margin: 0;
  font-size: clamp(16px, 2.4vw, 20px);
  line-height: 1.65;
  color: rgba(255, 255, 255, 0.90);
}

.home-intro__cta {
  margin-top: 14px;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  width: fit-content;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(0, 0, 0, 0.25);
  color: rgba(255, 255, 255, 0.78);
  font-size: 12px;
  font-weight: 750;
}

.home-hero {
  padding: 18px;
  display: grid;
  gap: 12px;
  position: relative;
  overflow: hidden;
}

.home-hero::before {
  content: "";
  position: absolute;
  inset: -2px;
  background: radial-gradient(700px 420px at 20% 10%, rgba(124, 58, 237, 0.22), transparent 60%),
    radial-gradient(700px 420px at 90% 20%, rgba(34, 211, 238, 0.16), transparent 58%);
  pointer-events: none;
}

.home-hero > * {
  position: relative;
  z-index: 1;
}

.home-hero__title {
  margin: 0;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.18;
  font-weight: 860;
  letter-spacing: 0.2px;
}

.home-hero__desc {
  margin: 0;
  color: rgba(255, 255, 255, 0.74);
  line-height: 1.7;
  font-size: 14px;
}

.home-hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 2px;
}

.home-section {
  display: grid;
  gap: 12px;
}

.home-section__header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding: 0 2px;
}

.home-section__title {
  font-weight: 850;
  letter-spacing: 0.2px;
}

.home-section__subtitle {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.62);
}

.home-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
}

.field {
  padding: 14px;
  display: grid;
  gap: 10px;
}

.field__head {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}

.field__icon {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.10), rgba(255, 255, 255, 0.03));
  display: grid;
  place-items: center;
  color: rgba(255, 255, 255, 0.84);
  flex: 0 0 auto;
}

.field__icon svg {
  width: 22px;
  height: 22px;
}

.field__title {
  font-weight: 850;
  letter-spacing: 0.2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.field__en {
  margin-left: 6px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.62);
  font-size: 12px;
}

.field__desc {
  margin: 0;
  color: rgba(255, 255, 255, 0.70);
  line-height: 1.7;
  font-size: 13px;
}

.field__points {
  margin: 0;
  padding-left: 18px;
  color: rgba(255, 255, 255, 0.68);
  line-height: 1.7;
  font-size: 13px;
  display: grid;
  gap: 6px;
}

.home-cta {
  padding: 16px;
  display: grid;
  gap: 10px;
}

.home-cta__title {
  font-weight: 850;
  letter-spacing: 0.2px;
}

.home-cta__desc {
  color: rgba(255, 255, 255, 0.68);
  font-size: 13px;
  line-height: 1.7;
}

.home-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

@media (max-width: 560px) {
  .home-hero__desc {
    font-size: 13px;
  }
  .home-grid {
    grid-template-columns: 1fr;
  }
}