/**
 * index.css — DOTUTO landing: luxury elegant, fullscreen, slider chọn vai trò.
 * Màu D/logo giống teacher: #059669 / #047857.
 */
:root {
  --index-brand: #059669;
  --index-brand-dark: #047857;
  --index-brand-glow: rgba(5, 150, 105, 0.4);
  --index-bg-deep: #0c0f14;
  --index-bg-mid: #111827;
  --index-text: #f1f5f9;
  --index-text-muted: #94a3b8;
  --index-card-bg: rgba(255, 255, 255, 0.06);
  --index-card-border: rgba(255, 255, 255, 0.08);
  --index-reel-w: 90vw;
  --index-slide-w: min(420px, 85vw);
}

* {
  box-sizing: border-box;
}

html {
  height: 100%;
}

body.index-page {
  margin: 0;
  min-height: 100%;
  min-height: 100dvh;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--index-text);
  overflow-x: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
  position: relative;
}

/* ——— Background AI-style ——— */
.index-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  overflow: hidden;
}

.index-bg-gradient {
  position: absolute;
  inset: -50%;
  background:
    radial-gradient(ellipse 80% 60% at 20% 20%, rgba(5, 150, 105, 0.15) 0%, transparent 50%),
    radial-gradient(ellipse 70% 50% at 80% 80%, rgba(4, 120, 87, 0.12) 0%, transparent 50%),
    radial-gradient(ellipse 100% 80% at 50% 50%, rgba(15, 23, 42, 0.9) 0%, #0c0f14 70%);
  animation: index-bg-pulse 12s ease-in-out infinite alternate;
}

.index-bg-mesh {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.02) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 80% at 50% 50%, black 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 80% 80% at 50% 50%, black 0%, transparent 70%);
}

.index-bg-shine {
  position: absolute;
  inset: 0;
  background: linear-gradient(125deg, transparent 30%, rgba(255,255,255,.03) 50%, transparent 70%);
  animation: index-shine 8s ease-in-out infinite;
}

@keyframes index-bg-pulse {
  from { opacity: 0.95; transform: scale(1); }
  to   { opacity: 1;   transform: scale(1.05); }
}

@keyframes index-shine {
  0%, 100% { opacity: 0; transform: translateX(-20%) skewX(-10deg); }
  50%      { opacity: 1; transform: translateX(20%) skewX(-10deg); }
}

/* ——— Content (above bg) ——— */
.index-content {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 960px;
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

/* ——— Logo DOTUTO ——— */
.index-header {
  text-align: center;
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
}

.index-logo {
  display: inline-flex;
  align-items: center;
  gap: 0;
  letter-spacing: -0.02em;
}

.index-logo-d {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 0.75rem;
  background: linear-gradient(180deg, var(--index-brand) 0%, var(--index-brand-dark) 100%);
  color: #fff;
  font-weight: 800;
  font-size: 1.5rem;
  line-height: 1;
  box-shadow: 0 4px 20px var(--index-brand-glow);
}

.index-logo-text {
  font-size: clamp(1.5rem, 5vw, 2rem);
  font-weight: 700;
  color: var(--index-text);
  margin-left: 0.25rem;
  letter-spacing: 0.02em;
}

.index-tagline {
  margin: 0.5rem 0 0;
  font-size: clamp(0.85rem, 2.5vw, 1rem);
  color: var(--index-text-muted);
  font-weight: 400;
}

/* ——— Reel / Slider ——— */
.index-reel {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.index-reel-track {
  display: flex;
  width: var(--index-reel-w);
  max-width: 900px;
  scroll-snap-type: x mandatory;
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-width: none;
  -ms-overflow-style: none;
  scroll-behavior: smooth;
  gap: 2rem;
  padding: 0.5rem 0;
}

.index-reel-track::-webkit-scrollbar {
  display: none;
}

.index-slide {
  flex: 0 0 var(--index-slide-w);
  width: var(--index-slide-w);
  scroll-snap-align: center;
  scroll-snap-stop: always;
}

.index-slide-inner {
  background: var(--index-card-bg);
  border: 1px solid var(--index-card-border);
  border-radius: 1.25rem;
  padding: clamp(1.5rem, 4vw, 2rem);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  min-height: 220px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.index-slide-inner:hover {
  transform: translateY(-2px);
  box-shadow: 0 20px 40px rgba(0,0,0,0.2);
}

.index-slide-title {
  margin: 0 0 0.5rem;
  font-size: clamp(1.25rem, 3.5vw, 1.5rem);
  font-weight: 700;
  color: var(--index-text);
}

.index-slide-desc {
  margin: 0 0 1.25rem;
  font-size: 0.9rem;
  color: var(--index-text-muted);
  line-height: 1.5;
}

/* ——— CTA Buttons (glow, sparkle) ——— */
.index-cta {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.75rem;
  border-radius: 9999px;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.3s ease;
}

.index-cta:hover {
  transform: scale(1.03);
}

.index-cta:active {
  transform: scale(0.98);
}

.index-cta--student {
  background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
  color: #fff;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.45);
}

.index-cta--student:hover {
  box-shadow: 0 8px 32px rgba(37, 99, 235, 0.5);
}

.index-cta--teacher {
  background: linear-gradient(135deg, var(--index-brand) 0%, var(--index-brand-dark) 100%);
  color: #fff;
  box-shadow: 0 4px 20px var(--index-brand-glow);
}

.index-cta--teacher:hover {
  box-shadow: 0 8px 32px rgba(5, 150, 105, 0.5);
}

.index-cta-shine {
  position: absolute;
  inset: 0;
  background: linear-gradient(110deg, transparent 25%, rgba(255,255,255,.25) 50%, transparent 75%);
  transform: translateX(-100%) skewX(-15deg);
  animation: index-cta-shine 3s ease-in-out infinite;
}

@keyframes index-cta-shine {
  0%   { transform: translateX(-100%) skewX(-15deg); }
  50%  { transform: translateX(100%) skewX(-15deg); }
  100% { transform: translateX(100%) skewX(-15deg); }
}

.index-cta-text {
  position: relative;
  z-index: 1;
}

/* ——— Dots ——— */
.index-reel-dots {
  display: flex;
  gap: 0.5rem;
  margin-top: 1.25rem;
}

.index-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  border: none;
  background: var(--index-text-muted);
  cursor: pointer;
  padding: 0;
  transition: background 0.3s ease, transform 0.2s ease;
}

.index-dot:hover {
  background: var(--index-text);
}

.index-dot--active {
  background: var(--index-brand);
  box-shadow: 0 0 12px var(--index-brand-glow);
  transform: scale(1.2);
}

.index-swipe-hint {
  margin: 0.75rem 0 0;
  font-size: 0.75rem;
  color: var(--index-text-muted);
}

/* ——— Admin (góc nhỏ) ——— */
.index-admin {
  position: fixed;
  bottom: 2.5rem;
  right: 1rem;
  z-index: 10;
  font-size: 0.7rem;
  color: var(--index-text-muted);
  text-decoration: none;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: color 0.2s ease, background 0.2s ease;
}

.index-admin:hover {
  color: var(--index-text);
  background: rgba(255,255,255,0.06);
}

/* ——— Footer hotline ——— */
.index-footer {
  position: relative;
  z-index: 1;
  margin-top: auto;
  padding: 0.75rem 1rem;
  font-size: 0.75rem;
  color: var(--index-text-muted);
}

.index-footer-tel {
  color: var(--index-brand);
  text-decoration: none;
  font-weight: 600;
}

.index-footer-tel:hover {
  text-decoration: underline;
}

/* ——— Desktop: 2 slides visible, centered ——— */
@media (min-width: 768px) {
  :root {
    --index-reel-w: 100%;
    --index-slide-w: min(380px, 42%);
  }

  .index-reel-track {
    justify-content: center;
    overflow: visible;
    scroll-snap-type: none;
  }

  .index-slide {
    flex: 0 0 var(--index-slide-w);
  }
}

@media (min-width: 1024px) {
  .index-reel-track {
    gap: 2.5rem;
  }
}