/* ============================================================
   main.css — Design system + layout chung (trang chủ, header, footer)
   ------------------------------------------------------------
   Hướng thiết kế: "SaaS sản phẩm" — nền sáng, khoảng trắng rộng rãi,
   card bo góc mềm với shadow tinh tế, một điểm nhấn gradient "spotlight"
   phía sau khối hero, và một accent màu chủ đạo có thể tuỳ biến theo
   Settings (--accent) để mỗi site vẫn giữ được bản sắc riêng.
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  /* ── Màu nền tảng (trung tính, mát) ── */
  --canvas:      #F6F7FB;
  --surface:     #FFFFFF;
  --surface-2:   #F0F2F8;
  --border:      #E4E7F0;
  --border-strong: #D3D7E4;

  /* ── Chữ ── */
  --text:        #10141F;
  --text-2:      #5B6472;
  --text-3:      #8A93A3;

  /* ── Accent (đổi được qua Settings > accent_color) ── */
  --accent:        #1877f2;
  --accent-ink:    #FFFFFF;
  --accent-soft:   color-mix(in srgb, var(--accent) 12%, white);
  --accent-strong: color-mix(in srgb, var(--accent) 82%, black);

  /* ── Màu phụ trợ ── */
  --ember:       #F59E0B;
  --success:     #16A34A;
  --danger:      #E11D48;

  /* ── Bo góc ── */
  --radius-sm:   10px;
  --radius-md:   14px;
  --radius-lg:   20px;
  --radius-pill: 999px;

  /* ── Đổ bóng ── */
  --shadow-xs: 0 1px 2px rgba(16, 20, 31, .04);
  --shadow-sm: 0 2px 10px rgba(16, 20, 31, .06);
  --shadow-md: 0 10px 28px rgba(16, 20, 31, .08);
  --shadow-lg: 0 28px 56px -16px rgba(16, 20, 31, .22);

  /* ── Font ── */
  --font-display: 'Manrope', 'Inter', system-ui, sans-serif;
  --font: 'Inter', system-ui, -apple-system, sans-serif;
}

html { -webkit-text-size-adjust: 100%; }

body {
  background: var(--canvas);
  color: var(--text);
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.55;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { display: block; width: 100%; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Header ───────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: blur(14px) saturate(160%);
  -webkit-backdrop-filter: blur(14px) saturate(160%);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  letter-spacing: -.01em;
  color: var(--text);
}

.logo svg { flex-shrink: 0; filter: drop-shadow(0 4px 10px rgba(16, 20, 31, .18)); }

.video-count {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text-2);
  background: var(--surface-2);
  border: 1px solid var(--border);
  padding: 6px 14px 6px 10px;
  border-radius: var(--radius-pill);
  white-space: nowrap;
}

.video-count::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--success) 18%, transparent);
  flex-shrink: 0;
}

.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text-2);
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-xs);
  transition: border-color .15s, color .15s, box-shadow .15s;
}
.btn-back:hover { color: var(--text); border-color: var(--border-strong); box-shadow: var(--shadow-sm); }

/* ── Page tabs (đa page) ──────────────────────────────── */
.page-tabs {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding: 0 0 18px;
  scrollbar-width: none;
}
.page-tabs::-webkit-scrollbar { display: none; }

.page-tab {
  flex-shrink: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-2);
  font-family: var(--font);
  font-size: 13px;
  font-weight: 600;
  padding: 8px 18px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s, box-shadow .15s;
  white-space: nowrap;
}

.page-tab:hover { border-color: var(--border-strong); color: var(--text); }

.page-tab.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-ink);
  box-shadow: 0 6px 16px -4px color-mix(in srgb, var(--accent) 55%, transparent);
}

/* ── Hero ─────────────────────────────────────────────── */
.hero {
  position: relative;
  padding: 48px 32px;
  margin: 28px 0 32px;
  text-align: left;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  overflow: hidden;
  isolation: isolate;
}

/* Signature: spotlight gradient blob phía sau nội dung hero */
.hero::before {
  content: '';
  position: absolute;
  z-index: -1;
  top: -140px;
  right: -120px;
  width: 420px;
  height: 420px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, color-mix(in srgb, var(--accent) 30%, transparent), transparent 70%);
  filter: blur(4px);
}
.hero::after {
  content: '';
  position: absolute;
  z-index: -1;
  bottom: -160px;
  left: -80px;
  width: 340px;
  height: 340px;
  border-radius: 50%;
  background: radial-gradient(circle at 60% 60%, color-mix(in srgb, var(--ember) 22%, transparent), transparent 70%);
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--accent-strong);
  background: var(--accent-soft);
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  margin-bottom: 16px;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 34px);
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1.2;
  margin-bottom: 10px;
  max-width: 640px;
}

.hero p {
  color: var(--text-2);
  font-size: 15px;
  max-width: 560px;
}

@media (max-width: 640px) {
  .hero { padding: 32px 20px; margin: 20px 0 24px; }
}

/* ── Sort bar ─────────────────────────────────────────── */
.sort-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 22px;
}

.sort-label {
  font-size: 12px;
  color: var(--text-3);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .05em;
  white-space: nowrap;
  margin-right: 2px;
}

.sort-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 15px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text-2);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all .15s;
  font-family: var(--font);
  white-space: nowrap;
}

.sort-btn:hover { color: var(--text); border-color: var(--border-strong); }

.sort-btn.active {
  background: var(--text);
  border-color: var(--text);
  color: var(--surface);
}

.sort-btn .sort-icon { font-size: 12px; opacity: .85; }

/* ── Video Grid — Reels layout (dọc) ─────────────────── */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(190px, 1fr));
  gap: 20px;
  padding-bottom: 40px;
}

@media (max-width: 600px) {
  .video-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
}

/* ── Video Card ───────────────────────────────────────── */
.video-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  cursor: pointer;
  transition: transform .18s cubic-bezier(.2,.8,.2,1), box-shadow .18s, border-color .18s;
  position: relative;
  box-shadow: var(--shadow-xs);
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

.card-thumb {
  position: relative;
  width: 100%;
  aspect-ratio: 9 / 16;
  background: var(--surface-2);
  overflow: hidden;
}

.card-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .35s ease;
}
.video-card:hover .card-thumb img { transform: scale(1.045); }

.thumb-placeholder {
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--surface-2) 0%, var(--border) 100%);
}

.card-play {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(180deg, rgba(16,20,31,0) 55%, rgba(16,20,31,.55) 100%);
  opacity: 0;
  transition: opacity .18s;
}

.video-card:hover .card-play { opacity: 1; }

.card-play svg { width: 44px; height: 44px; }
.card-play circle { fill: rgba(255,255,255,.92); }
.card-play path { fill: var(--text); }

.card-duration {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: rgba(16, 20, 31, .72);
  backdrop-filter: blur(4px);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  padding: 3px 8px;
  border-radius: 6px;
  letter-spacing: .2px;
}

.card-body { padding: 14px; }

.card-title {
  font-size: 13.5px;
  font-weight: 700;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  color: var(--text);
  margin-bottom: 8px;
  letter-spacing: -.005em;
}

.card-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 3px 10px;
  font-size: 11.5px;
  font-weight: 600;
  color: var(--text-3);
  font-variant-numeric: tabular-nums;
}

.meta-date { margin-left: auto; font-weight: 500; }

/* ── Load more / Infinite scroll indicator ────────────── */
.load-sentinel { height: 1px; }

.loading-spinner {
  display: none;
  text-align: center;
  padding: 32px;
  color: var(--text-2);
  font-size: 13.5px;
  font-weight: 600;
}
.loading-spinner.active { display: block; }

.spinner {
  display: inline-block;
  width: 22px;
  height: 22px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin .7s linear infinite;
  margin-bottom: 10px;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* ── Empty state ──────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 72px 20px;
  color: var(--text-2);
  background: var(--surface);
  border: 1px dashed var(--border-strong);
  border-radius: var(--radius-lg);
  margin: 24px 0 40px;
}
.empty-state svg { margin: 0 auto 18px; }
.empty-state p:first-of-type { font-weight: 700; color: var(--text); margin-bottom: 4px; font-size: 15px; }
.hidden { display: none !important; }

/* ── Footer ───────────────────────────────────────────── */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0 40px;
  text-align: center;
  font-size: 13px;
  color: var(--text-3);
}
.site-footer a { color: var(--accent); font-weight: 600; }
.site-footer a:hover { text-decoration: underline; }
.page-tabs {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  overflow-y: hidden;
  flex-wrap: nowrap;
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;      /* Firefox: ẩn scrollbar */
  -ms-overflow-style: none;   /* IE/Edge */
  padding-bottom: 4px;
  /* để không bị header container che mất cạnh phải */
  mask-image: linear-gradient(to right, black 92%, transparent 100%);
  -webkit-mask-image: linear-gradient(to right, black 92%, transparent 100%);
}

.page-tabs::-webkit-scrollbar {
  display: none;              /* Chrome/Safari: ẩn scrollbar */
}

.page-tab {
  flex: 0 0 auto;             /* quan trọng: không bị co lại/cắt */
  white-space: nowrap;
}
.page-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}