:root{--bg:#f1f5f9;--card:#fff;--text:#1e293b;--text-secondary:#64748b;--border:#e2e8f0;--primary:#6366f1;--primary-hover:#4f46e5;--danger:#ef4444}.app.dark{--bg:#0f172a;--card:#1e293b;--text:#e2e8f0;--text-secondary:#94a3b8;--border:#334155;--primary:#818cf8;--primary-hover:#6366f1}*{box-sizing:border-box;margin:0;padding:0}body{font-family:Segoe UI,sans-serif}.app{background:var(--bg);min-height:100vh;color:var(--text);padding:2rem}nav{background:var(--card);border:1px solid var(--border);border-radius:12px;justify-content:space-between;align-items:center;max-width:1200px;margin:0 auto 2rem;padding:1rem 2rem;display:flex}.logo{color:var(--primary)}.links{gap:1.5rem;display:flex}.links a{color:var(--text);font-weight:600;text-decoration:none}.links a:hover{color:var(--primary)}.page,.users-page{max-width:1200px;margin:auto}.card{background:var(--card);border:1px solid var(--border);border-radius:16px;padding:2rem}.card h1{margin-bottom:1rem}.card h3{margin:1rem 0 .5rem}.card p{line-height:1.6}.card ul{padding-left:1.2rem}.card li{margin:.4rem 0}.form-grid{grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:1rem;margin:1.5rem 0;display:grid}input{background:var(--card);width:100%;color:var(--text);border:1px solid var(--border);border-radius:8px;padding:12px}.btn-row,.sort-bar{gap:1rem;display:flex}.sort-bar{margin:1.5rem 0}button{cursor:pointer;background:var(--primary);color:#fff;border:none;border-radius:8px;padding:10px 16px}button:hover{background:var(--primary-hover)}.theme-btn{position:fixed;top:20px;right:20px}.user-list{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:1rem;display:grid}.user-card{background:var(--card);border:1px solid var(--border);border-radius:12px;padding:1rem}.user-card h3{margin-bottom:.5rem}.user-card p{margin-bottom:.4rem}.user-card button{width:100%;margin-top:.5rem}.error{color:var(--danger);margin-top:1rem}.empty{text-align:center;color:var(--text-secondary);margin-top:2rem}@media (width<=768px){.app{padding:1rem}nav{flex-direction:column;gap:1rem}.btn-row,.sort-bar{flex-direction:column}}