/* Frontend styles */
.durdur-container { max-width: 1100px; margin: 0 auto; padding: 0 16px; }
.durdur-courses-grid, .durdur-chapters-grid { display:grid; gap:18px; margin: 8px 0 28px; }
.durdur-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.durdur-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.durdur-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
@media (max-width: 1024px) { .durdur-courses-grid, .durdur-chapters-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 640px) { .durdur-courses-grid, .durdur-chapters-grid { grid-template-columns: 1fr; } }

.durdur-card, .durdur-chapter-card { border: 1px solid #e5e7eb; border-radius: 16px; overflow: hidden; background: #fff; box-shadow: 0 6px 18px rgba(0,0,0,0.06); }
.durdur-card-media { background-size: cover; background-position: center; min-height: 160px; display:block; }
.durdur-card-body { padding: 16px 18px 20px; display: flex; flex-direction: column; gap: 10px; }
.durdur-card-title { font-size: 20px; margin: 0; font-weight: 800; }
.durdur-card-title a { text-decoration: none; color: #111827; }
.durdur-card-text { color: #4b5563; margin: 0; line-height: 1.55; font-size: 14px; }
.durdur-card-actions { display: flex; gap: 10px; margin-top: 6px; flex-wrap: wrap; }

.durdur-btn { display: inline-block; padding: 9px 14px; border-radius: 12px; text-decoration: none; background: linear-gradient(135deg, #047857, #16a34a); color: #fff; font-weight: 700; box-shadow: 0 3px 10px rgba(22,163,74,0.25); }
.durdur-btn:hover { filter: brightness(1.05); }
.durdur-btn-outline { background: transparent; border: 1px solid #16a34a; color: #047857; }

.durdur-section-title h2 { font-size: 22px; font-weight: 900; margin: 10px 0 6px; background: linear-gradient(135deg, #065f46, #16a34a); -webkit-background-clip: text; color: transparent; }

.durdur-chapter-head { display:flex; align-items:center; gap:14px; padding:14px; }
.durdur-chapter-thumb { width:88px; height:72px; border-radius:12px; background:#f3f4f6; background-size:cover; background-position:center; flex:0 0 auto; }
.durdur-chapter-meta { flex:1; min-width:0; }
.durdur-chapter-title { margin:0 0 4px; font-size:18px; font-weight:800; }
.durdur-chapter-excerpt { margin:0; color:#6b7280; font-size:13px; }
.durdur-toggle { border:1px solid #d1fae5; background:#ecfdf5; color:#065f46; border-radius:10px; padding:8px 12px; cursor:pointer; font-weight:700; }
.durdur-chapter-body { padding:0 16px 16px; border-top:1px dashed #e5e7eb; }
.durdur-video-wrap { margin:12px 0; aspect-ratio:16/9; max-width:100%; }
.durdur-video-wrap iframe, .durdur-video-wrap video { width:100%; height:100%; border:0; border-radius:14px; }
.durdur-pdf-actions, .durdur-course-pdf-actions { display:flex; gap:10px; margin:10px 0 18px; flex-wrap:wrap; }

.durdur-course-video-wrap { margin: 10px 0 18px; aspect-ratio:16/9; }
.durdur-course-video-wrap iframe { width:100%; height:100%; border:0; border-radius:14px; }

.durdur-locked{border:1px dashed #d1fae5;background:#ecfdf5;padding:18px;border-radius:14px}
.durdur-locked h3{margin:0 0 6px;font-weight:900;color:#065f46}

@media (max-width: 480px) {
  .durdur-card-body { padding: 14px; }
  .durdur-chapter-head { padding: 12px; }
  .durdur-chapter-thumb { width: 78px; height: 64px; }
}