/* simple, clean UI */
.da-grid{display:grid;gap:16px}
.da-grid.cols-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.da-grid.cols-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.da-grid.cols-4{grid-template-columns:repeat(4,minmax(0,1fr))}
@media(max-width:782px){.da-grid{grid-template-columns:1fr !important}}
.da-card{border:1px solid #e5e7eb;border-radius:16px;padding:16px;background:#fff;box-shadow:0 2px 10px rgba(0,0,0,.03)}
.da-card-title{margin:0 0 8px}
.da-progress{height:8px;background:#f1f5f9;border-radius:999px;overflow:hidden;margin:8px 0}
.da-progress span{display:block;height:100%;background:#2563eb}
.da-meta{font-size:.85rem;color:#64748b}
.da-btn{display:inline-block;margin-top:10px;padding:10px 14px;border-radius:10px;background:#111827;color:#fff;text-decoration:none}
.da-btn.primary{background:#2563eb}
.da-hint{color:#64748b}
.da-msg{padding:12px;border:1px dashed #e5e7eb;border-radius:12px;background:#fafafa}
.da-course{border:1px solid #e5e7eb;border-radius:16px;padding:16px;background:#fff}
.da-title{margin-top:0}
.da-section{margin-bottom:20px}
.da-sec-title{margin:10px 0}
.da-lesson{border:1px solid #eef2f7;border-radius:12px;padding:12px;margin-bottom:12px}
.da-lesson.done{border-color:#bbf7d0;background:#f0fdf4}
.da-lesson-title{margin:4px 0 8px}
.da-notes{color:#334155}
.da-lesson .da-toggle{margin-top:8px;padding:8px 12px;border-radius:8px;border:1px solid #e5e7eb;background:#f8fafc;cursor:pointer}
.da-lesson .da-toggle:hover{background:#f1f5f9}