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

body {
  background: #0d1117;
  color: #e6edf3;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  min-height: 100vh;
}

header {
  background: #161b22;
  border-bottom: 1px solid #30363d;
  padding: 1.25rem;
  text-align: center;
  position: sticky;
  top: 0;
  z-index: 100;
}

header h1 {
  font-size: 1.5rem;
  background: linear-gradient(135deg, #8b5cf6, #ff6b35);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.25rem;
}

.admin-link {
  display: inline-block;
  font-size: 0.8125rem;
  color: #8b949e;
  text-decoration: none;
  transition: color 0.2s;
}

.admin-link:hover {
  color: #8b5cf6;
}

.container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1rem;
}

.post-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.post-card {
  background: #161b22;
  border: 1px solid #30363d;
  border-radius: 12px;
  overflow: hidden;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
  border-color: #8b5cf6;
}

.post-card:active {
  transform: translateY(-1px);
}

.post-card img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  display: block;
}

.post-card .card-title {
  padding: 1rem;
  font-size: 1rem;
  font-weight: 600;
}

.post-detail {
  display: none;
}

.post-detail.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.post-grid.hidden {
  display: none;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: #8b5cf6;
  cursor: pointer;
  font-size: 1rem;
  margin-bottom: 1.5rem;
  background: none;
  border: none;
  padding: 0.5rem 0;
  transition: opacity 0.2s;
  font-family: inherit;
}

.back-btn:hover {
  opacity: 0.8;
}

.detail-thumb {
  width: 100%;
  max-height: 400px;
  object-fit: cover;
  border-radius: 12px;
  margin-bottom: 1rem;
  border: 1px solid #30363d;
}

.detail-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  background: linear-gradient(135deg, #e6edf3, #8b5cf6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.quality-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.quality-btn {
  padding: 0.75rem 2.5rem;
  border-radius: 8px;
  border: none;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
  font-family: inherit;
}

.quality-btn:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.quality-btn:active {
  transform: scale(0.97);
}

.btn-480p {
  background: #2563eb;
  color: #fff;
}

.btn-720p {
  background: #16a34a;
  color: #fff;
}

.btn-1080p {
  background: #dc2626;
  color: #fff;
}

@media (max-width: 640px) {
  .post-grid {
    grid-template-columns: 1fr;
  }

  .quality-buttons {
    flex-direction: column;
  }

  .quality-btn {
    width: 100%;
    text-align: center;
  }

  .detail-title {
    font-size: 1.35rem;
  }
}