:root{--bg:#faf7f2;--surface:#ffffff;--text:#2b2320;--muted:#8a7f77;--accent:#c4623a;--accent-dark:#a34e2c;--border:#e8e0d6;--danger:#b3402e}*{box-sizing:border-box}body{margin:0;font-family:Segoe UI,system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.55}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}button{font:inherit;cursor:pointer;background:var(--accent);color:#fff;border:none;border-radius:8px;padding:.55rem 1.1rem}button:hover{background:var(--accent-dark)}button:disabled{opacity:.5;cursor:not-allowed}button.ghost{background:transparent;color:var(--accent);border:1px solid var(--border)}button.danger{background:var(--danger)}input,select{font:inherit;padding:.55rem .75rem;border:1px solid var(--border);border-radius:8px;background:var(--surface);color:var(--text);width:100%}.center-page{min-height:100vh;display:flex;align-items:center;justify-content:center;flex-direction:column;gap:1rem;padding:1rem}.container{max-width:960px;margin:0 auto;padding:1.5rem 1rem 4rem}.topbar{display:flex;align-items:center;justify-content:space-between;gap:1rem;padding:.9rem 1rem;background:var(--surface);border-bottom:1px solid var(--border)}.topbar .brand{font-weight:700;color:var(--text);font-size:1.05rem}.topbar nav{display:flex;gap:1rem;align-items:center}.card{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:1.25rem}.card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));grid-gap:1rem;gap:1rem}.lesson-row{display:flex;align-items:center;justify-content:space-between;gap:1rem;padding:.8rem 1rem;border:1px solid var(--border);border-radius:10px;background:var(--surface);margin-bottom:.6rem}.muted{color:var(--muted);font-size:.9rem}.error-text{color:var(--danger);font-size:.92rem}.form-stack{display:flex;flex-direction:column;gap:.8rem;width:100%;max-width:380px}table.admin-table{width:100%;border-collapse:collapse;background:var(--surface);border:1px solid var(--border);border-radius:10px;overflow:hidden}table.admin-table td,table.admin-table th{text-align:left;padding:.6rem .8rem;border-bottom:1px solid var(--border);font-size:.92rem}table.admin-table th{background:var(--bg);font-weight:600}.player-shell{position:relative;background:#000;border-radius:12px;overflow:hidden;-moz-user-select:none;user-select:none;-webkit-user-select:none}.player-shell video{display:block;width:100%;aspect-ratio:16/9;background:#000}.player-shell:-webkit-full-screen{border-radius:0}.player-shell:fullscreen{border-radius:0}.player-shell:-webkit-full-screen video{height:100%;aspect-ratio:auto}.player-shell:fullscreen video{height:100%;aspect-ratio:auto}.watermark{position:absolute;pointer-events:none;opacity:.25;color:#fff;font-size:.8rem;font-family:monospace;white-space:nowrap;text-shadow:0 0 4px rgba(0,0,0,.8);z-index:10;transition:top 1.2s ease,left 1.2s ease}.player-controls{position:absolute;right:.6rem;bottom:3.2rem;z-index:11}.player-controls button{background:rgba(0,0,0,.55);font-size:.8rem;padding:.35rem .7rem}.player-controls button:hover{background:rgba(0,0,0,.8)}