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

html, body {
  height: 100%;
  overflow: hidden;
  background: #000;
  color: #fff;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  user-select: none;
}

/* ── Feed Container ── */
.feed {
  height: 100vh;
  height: 100dvh;
  overflow-y: scroll;
  scroll-snap-type: y mandatory;
  -webkit-overflow-scrolling: touch;
}

/* ── Individual Slide ── */
.slide {
  height: 100vh;
  height: 100dvh;
  scroll-snap-align: start;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #000;
  overflow: hidden;
}

/* ── YouTube Player Container ── */
.player-container {
  width: 100%;
  aspect-ratio: 16 / 9;
  position: relative;
  background-color: #111;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

.player-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
  pointer-events: none;
}

/* ── Video Info Overlay ── */
.overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 60px 16px 20px;
  padding-bottom: max(20px, env(safe-area-inset-bottom, 0px));
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.8));
  z-index: 10;
  display: flex;
  align-items: flex-end;
  gap: 12px;
  opacity: 1;
  transition: opacity 0.4s ease;
}

.overlay.hidden {
  opacity: 0;
  pointer-events: none;
}

.video-info {
  flex: 1;
  min-width: 0;
}

.video-title {
  font-size: 17px;
  font-weight: 700;
  line-height: 1.3;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.9);
}

.video-desc {
  font-size: 13px;
  line-height: 1.4;
  margin-top: 4px;
  opacity: 0.85;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.9);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 6px;
}

.video-year {
  display: inline-block;
  padding: 2px 8px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 4px;
  font-size: 11px;
  font-weight: 600;
}

.video-category {
  display: inline-block;
  padding: 2px 8px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 4px;
  font-size: 11px;
  text-transform: capitalize;
}

/* ── Heart Button ── */
.heart-btn {
  background: none;
  border: none;
  color: #fff;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  cursor: pointer;
  flex-shrink: 0;
  padding: 8px;
  -webkit-tap-highlight-color: transparent;
}

.heart-icon {
  width: 36px;
  height: 36px;
  transition: transform 0.3s ease;
}

.heart-icon path {
  fill: transparent;
  stroke: #fff;
  stroke-width: 1.5;
  transition: fill 0.3s ease, stroke 0.3s ease;
}

.heart-btn.hearted .heart-icon path {
  fill: #fe2c55;
  stroke: #fe2c55;
}

.heart-btn.hearted .heart-icon {
  animation: heartPop 0.4s ease;
}

/* ── Double-Tap Heart Burst ── */
.heart-burst {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0);
  width: 100px;
  height: 100px;
  pointer-events: none;
  z-index: 20;
  opacity: 0;
}

.heart-burst svg {
  width: 100%;
  height: 100%;
}

.heart-burst.animate {
  animation: burstHeart 0.8s ease forwards;
}

@keyframes heartPop {
  0% { transform: scale(1); }
  50% { transform: scale(1.4); }
  100% { transform: scale(1); }
}

@keyframes burstHeart {
  0% { transform: translate(-50%, -50%) scale(0); opacity: 1; }
  30% { transform: translate(-50%, -50%) scale(1.3); opacity: 1; }
  60% { transform: translate(-50%, -50%) scale(1); opacity: 0.8; }
  100% { transform: translate(-50%, -50%) scale(1.4); opacity: 0; }
}

/* ── Mute Hint Overlay ── */
.mute-hint {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  cursor: pointer;
  opacity: 1;
  transition: opacity 0.3s ease;
}

.mute-hint.dismissed {
  opacity: 0;
  pointer-events: none;
}

.mute-hint-content {
  text-align: center;
  animation: pulse 2s ease-in-out infinite;
}

.mute-hint-content p {
  margin-top: 12px;
  font-size: 16px;
  opacity: 0.9;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.9; }
  50% { transform: scale(1.05); opacity: 1; }
}

/* ── Loading Spinner ── */
.loader {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: #000;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  z-index: 50;
  transition: opacity 0.4s ease;
}

.loader.done {
  opacity: 0;
  pointer-events: none;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid rgba(255, 255, 255, 0.2);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.loader-text {
  font-size: 14px;
  opacity: 0.6;
}

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

/* ── Swipe Hint (shown on first visit) ── */
.swipe-hint {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 30;
  text-align: center;
  opacity: 0;
  animation: swipeHintIn 0.5s ease 1.5s forwards;
  pointer-events: none;
}

.swipe-hint.dismissed {
  animation: swipeHintOut 0.3s ease forwards;
}

.swipe-hint svg {
  animation: bobUp 1.5s ease-in-out infinite;
}

.swipe-hint p {
  font-size: 13px;
  opacity: 0.7;
  margin-top: 4px;
}

@keyframes bobUp {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes swipeHintIn {
  from { opacity: 0; transform: translateX(-50%) translateY(10px); }
  to { opacity: 1; transform: translateX(-50%) translateY(0); }
}

@keyframes swipeHintOut {
  from { opacity: 1; }
  to { opacity: 0; }
}

/* ── Portrait Mode: fill screen, crop sides ── */
@media (max-aspect-ratio: 16/9) {
  .player-container {
    aspect-ratio: auto;
    height: 100%;
    overflow: hidden;
  }

  .player-container iframe {
    width: calc(100dvh * 16 / 9);
    height: 100dvh;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
  }
}