*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{font-family:system-ui,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;color:#213547;background-color:#fff}body{min-width:320px;min-height:100vh}a{color:inherit;text-decoration:none}a:hover{text-decoration:underline}img{max-width:100%;display:block}#root{max-width:1280px;margin:0 auto;padding:0 2rem}nav{display:flex;align-items:center;justify-content:space-between;padding:1rem 0;border-bottom:1px solid #e5e7eb}nav ul{display:flex;list-style:none;gap:1.5rem;margin:0;padding:0}.courses-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:1.5rem;margin-top:1.5rem}.course-card{border:1px solid #e5e7eb;border-radius:12px;overflow:hidden;padding:1rem;display:flex;flex-direction:column;gap:.5rem}.course-card img{width:100%;border-radius:8px;object-fit:cover;aspect-ratio:16 / 9}.course-card-ghost{border:2px dashed #d1d5db;border-radius:12px;background:none;min-height:180px;display:flex;align-items:center;justify-content:center;font-size:2rem;color:#9ca3af;cursor:pointer;transition:border-color .2s,color .2s}.course-card-ghost:hover{border-color:#6b7280;color:#374151}.category-filters{display:flex;gap:.75rem;margin-top:1.5rem;flex-wrap:wrap}.category-filters button.active{background-color:#213547;color:#fff}.modal-backdrop{position:fixed;inset:0;background:#0006;display:flex;align-items:center;justify-content:center;z-index:100}.modal{background:#fff;border-radius:12px;padding:2rem;width:100%;max-width:520px;display:flex;flex-direction:column;gap:1rem}.modal form{display:flex;flex-direction:column;gap:.75rem}.modal textarea{resize:none;width:100%;box-sizing:border-box;overflow-y:auto;white-space:pre-wrap;word-wrap:break-word}.modal-actions{display:flex;justify-content:flex-end;gap:.75rem;margin-top:.5rem}.avatar-wrapper{position:relative;width:100px;height:100px;border-radius:50%;cursor:pointer;overflow:hidden;border:2px solid #e5e7eb;transition:border-color .2s}.avatar-wrapper:hover,.avatar-wrapper.drag-over{border-color:#213547}.avatar,.avatar-placeholder{width:100%;height:100%;object-fit:cover;border-radius:50%}.avatar-placeholder{display:flex;align-items:center;justify-content:center;background:#e5e7eb;font-size:2.5rem;font-weight:600;color:#374151}.avatar-overlay{position:absolute;inset:0;background:#00000080;color:#fff;display:flex;align-items:center;justify-content:center;font-size:.75rem;border-radius:50%}footer{margin-top:4rem;padding:1.5rem 0;border-top:1px solid #e5e7eb;text-align:center;font-size:.875rem;color:#6b7280}