*{box-sizing:border-box;margin:0;padding:0}:root{--ink: #14213d;--accent: #2563eb;--accent-dark: #1d4ed8;--bg: #f6f8fc;--card: #ffffff;--muted: #64748b;--danger: #dc2626;--ok: #16a34a;--radius: 14px;--shadow: 0 2px 10px rgba(20, 33, 61, .08)}body{font-family:system-ui,-apple-system,Segoe UI,sans-serif;background:var(--bg);color:var(--ink)}.landing{min-height:100vh;display:flex;flex-direction:column;background:linear-gradient(160deg,#eef4ff,#f6f8fc 45%,#fdf7ef)}.landing-nav{padding:20px 32px}.brand{font-size:17px;letter-spacing:.2px}.brand b{font-weight:700}.landing-hero{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:24px 16px 48px}.landing-hero h1{font-size:clamp(28px,4.5vw,44px);line-height:1.15;margin-bottom:14px}.landing-hero .sub{color:var(--muted);font-size:clamp(15px,2vw,18px);max-width:560px;margin-bottom:40px}.signin-cards{display:flex;gap:24px;flex-wrap:wrap;justify-content:center}.signin-card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:32px 28px;width:300px;display:flex;flex-direction:column;align-items:center;gap:10px}.signin-icon{font-size:34px}.signin-card h2{font-size:20px}.signin-card p{color:var(--muted);font-size:14px;line-height:1.45;min-height:60px}.fineprint{margin-top:32px;color:var(--muted);font-size:13px;max-width:460px}.landing-footer{text-align:center;padding:18px;color:var(--muted);font-size:12px}.btn-primary{display:inline-flex;align-items:center;gap:8px;justify-content:center;background:var(--accent);color:#fff;border:none;border-radius:10px;padding:11px 18px;font-size:14px;font-weight:600;cursor:pointer}.btn-primary:hover{background:var(--accent-dark)}.btn-primary:disabled{background:#a5b4d4;cursor:default}.btn-secondary{display:inline-block;margin-top:12px;color:var(--accent);font-weight:600;text-decoration:none;font-size:14px}.btn-link{background:none;border:none;color:var(--accent);cursor:pointer;font-size:13px;text-decoration:none}.btn-link.danger{color:var(--danger)}.shell{min-height:100vh;display:flex;flex-direction:column}.topbar{display:flex;justify-content:space-between;align-items:center;background:var(--card);box-shadow:var(--shadow);padding:14px 24px;position:sticky;top:0;z-index:5}.topbar-right{display:flex;align-items:center;gap:14px}.content{max-width:1000px;width:100%;margin:0 auto;padding:28px 20px 60px}.content h1{font-size:26px;margin-bottom:8px}.muted{color:var(--muted);font-size:14px}.card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:22px;margin-top:20px}.card.narrow{max-width:420px;text-align:center}.card h2{font-size:17px;margin-bottom:12px}.card p{line-height:1.5}.two-col{display:grid;grid-template-columns:1fr 1fr;gap:20px}@media(max-width:720px){.two-col{grid-template-columns:1fr}}.page-center{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:16px}.tile-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px;margin-top:24px}.tile{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;text-decoration:none;color:inherit;transition:transform .12s}.tile:hover{transform:translateY(-2px)}.tile.disabled{opacity:.55}.tile h3{font-size:16px;margin-bottom:6px}.tile p{color:var(--muted);font-size:13px}.row-form{display:flex;gap:10px;margin-top:8px}input,select,textarea{font-family:inherit;font-size:14px;padding:10px 12px;border:1px solid #d7dee9;border-radius:10px;outline:none;background:#fff;width:100%}input:focus,select:focus,textarea:focus{border-color:var(--accent)}select{width:auto}textarea{resize:vertical;margin-bottom:10px}.data-table{width:100%;border-collapse:collapse;font-size:14px}.data-table th{text-align:left;color:var(--muted);font-size:12px;text-transform:uppercase;letter-spacing:.4px;padding:8px 10px;border-bottom:1px solid #e6ecf4}.data-table td{padding:10px;border-bottom:1px solid #eef2f8}.role-pill{font-size:12px;font-weight:600;padding:3px 10px;border-radius:99px}.role-student{background:#e8f0fe;color:#1d4ed8}.role-teacher{background:#e7f7ee;color:#15803d}.role-superadmin{background:#fdeee0;color:#c2570b}.acc-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}.acc-grid label,.content label{font-size:13px;color:var(--muted);display:flex;flex-direction:column;gap:6px}@media(max-width:720px){.acc-grid{grid-template-columns:1fr}}.title-input{font-size:22px;font-weight:700;flex:1}.question-card{border:1px solid #e6ecf4;border-radius:12px;padding:14px;margin-top:14px}.check-row{display:flex!important;flex-direction:row!important;align-items:center;gap:8px;padding:6px 0;font-size:14px!important;color:var(--ink)!important}.publish-modal{border:2px solid var(--accent)}.error-banner{margin-top:16px;background:#fdecea;color:var(--danger);padding:10px 14px;border-radius:10px;font-size:14px}.ok-banner{margin-top:16px;background:#eaf7ef;color:var(--ok);padding:10px 14px;border-radius:10px;font-size:14px}.spinner{width:28px;height:28px;border:3px solid #dbe4f0;border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite;margin:20px auto}@keyframes spin{to{transform:rotate(360deg)}}