* { -webkit-tap-highlight-color: transparent; }

html, body {
  margin: 0;
  padding: 0;
  background: #f5f6fa;
  color: #111827;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}

::-webkit-scrollbar { width: 0; height: 0; display: none; }

.dt-shell {
  max-width: 720px;
  margin: 0 auto;
  min-height: 100vh;
  background: #f5f6fa;
  position: relative;
}

@media (min-width: 900px) {
  body { background: #e9ebf2; }
  .dt-shell {
    box-shadow: 0 0 0 1px rgba(15, 23, 42, .06), 0 24px 60px rgba(15, 23, 42, .12);
  }
}

/* 底部导航 */
.dt-tabbar {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  z-index: 40;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(12px);
  border-top: 1px solid rgba(15, 23, 42, .06);
  padding-bottom: env(safe-area-inset-bottom);
}

.dt-tabbar-inner {
  max-width: 720px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}

.dt-tab {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 8px 0 6px;
  font-size: 11px;
  color: #8a90a2;
  text-decoration: none;
}

.dt-tab svg { width: 22px; height: 22px; }
.dt-tab.nav-active { color: #4f46e5; font-weight: 700; }

/* 卡片 */
.dt-card {
  background: #fff;
  border-radius: 18px;
  box-shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 8px 24px rgba(15, 23, 42, .05);
}

/* 视频封面占位 */
.dt-cover {
  position: relative;
  width: 100%;
  aspect-ratio: 3 / 4;
  border-radius: 14px;
  overflow: hidden;
  background: linear-gradient(135deg, #c7d2fe, #a5b4fc 45%, #818cf8);
  display: flex;
  align-items: center;
  justify-content: center;
}

.dt-cover img { width: 100%; height: 100%; object-fit: cover; }

.dt-cover .ph {
  font-size: 34px;
  font-weight: 800;
  color: rgba(255, 255, 255, .88);
  text-shadow: 0 2px 10px rgba(0, 0, 0, .12);
}

.dt-badge {
  position: absolute;
  right: 6px;
  bottom: 6px;
  background: rgba(0, 0, 0, .55);
  color: #fff;
  font-size: 11px;
  padding: 2px 6px;
  border-radius: 6px;
}

/* 分类横滑 */
.dt-chips {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: 4px 16px 10px;
  scrollbar-width: none;
}

.dt-chip {
  flex: 0 0 auto;
  padding: 7px 14px;
  border-radius: 999px;
  background: #fff;
  color: #4b5563;
  font-size: 13px;
  border: 1px solid rgba(15, 23, 42, .06);
  white-space: nowrap;
}

.dt-chip.on {
  background: #4f46e5;
  color: #fff;
  border-color: #4f46e5;
  font-weight: 700;
}

/* Toast */
.dt-toast {
  position: fixed;
  left: 50%;
  bottom: 110px;
  transform: translate(-50%, 12px);
  background: rgba(17, 24, 39, .88);
  color: #fff;
  padding: 10px 18px;
  border-radius: 12px;
  font-size: 13px;
  max-width: 80vw;
  text-align: center;
  opacity: 0;
  pointer-events: none;
  transition: all .22s ease;
  z-index: 80;
}

.dt-toast.show { opacity: 1; transform: translate(-50%, 0); }

/* 骨架 */
.skeleton {
  background: linear-gradient(90deg, #eceef5 25%, #f7f8fc 37%, #eceef5 63%);
  background-size: 400% 100%;
  animation: sk 1.2s ease infinite;
}

@keyframes sk {
  0% { background-position: 100% 50%; }
  100% { background-position: 0 50%; }
}

.btn-primary {
  background: linear-gradient(135deg, #6366f1, #4f46e5);
  color: #fff;
  font-weight: 700;
  border-radius: 14px;
  box-shadow: 0 8px 20px rgba(79, 70, 229, .28);
}

.btn-primary:disabled { opacity: .55; box-shadow: none; }