:root {
    --bg: #f4f7fb;
    --surface: #ffffff;
    --surface-2: #eef3fb;
    --text: #132238;
    --muted: #627083;
    --primary: #0b5cab;
    --primary-dark: #073f78;
    --success: #0f8a4b;
    --danger: #b42318;
    --border: #d8e1ed;
    --shadow: 0 20px 50px rgba(19, 34, 56, .08);
}
* { box-sizing: border-box; }
body { margin: 0; font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; background: var(--bg); color: var(--text); }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
button, input, select, textarea { font: inherit; }
input, select, textarea { width: 100%; border: 1px solid var(--border); border-radius: 12px; padding: 12px 14px; margin-top: 6px; background: #fff; color: var(--text); }
textarea { resize: vertical; }
label { font-weight: 700; color: #27364d; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 14px 12px; border-bottom: 1px solid var(--border); text-align: left; vertical-align: top; }
th { color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: .04em; }
.guest-body { min-height: 100vh; display: grid; place-items: center; padding: 24px; background: linear-gradient(135deg, #062d57, #0b5cab 45%, #eef3fb 45%); }
.guest-shell { width: min(980px, 100%); min-height: 620px; display: grid; grid-template-columns: 1fr 1fr; background: var(--surface); border-radius: 30px; box-shadow: var(--shadow); overflow: hidden; }
.brand-panel { padding: 56px; color: #fff; background: radial-gradient(circle at top left, rgba(255,255,255,.22), transparent 32%), #062d57; display: flex; flex-direction: column; justify-content: center; }
.brand-mark { width: 74px; height: 74px; border-radius: 22px; background: #fff; color: var(--primary); display: grid; place-items: center; font-weight: 900; font-size: 26px; margin-bottom: 24px; overflow: hidden; }
.brand-mark img { width: 100%; height: 100%; object-fit: contain; padding: 4px; }
.brand-mark img:not([hidden]) + b { display: none; }
.guest-content { padding: 56px; display: flex; align-items: center; }
.auth-card { width: 100%; }
.auth-card h2, .auth-card h1 { margin: 0 0 12px; font-size: 32px; }
.eyebrow { margin: 0 0 8px; color: var(--primary); font-weight: 900; text-transform: uppercase; letter-spacing: .12em; font-size: 12px; }
.muted { color: var(--muted); font-weight: 500; }
.small { font-size: 14px; color: var(--muted); }
.is-hidden { display: none !important; }
.math-frac { display: inline-grid; grid-template-rows: auto auto; vertical-align: middle; text-align: center; line-height: 1; margin: 0 2px; }
.math-frac span:first-child { border-bottom: 1px solid currentColor; padding: 0 3px 2px; }
.math-frac span:last-child { padding: 2px 3px 0; }
.math-root { display: inline-flex; align-items: flex-start; gap: 2px; }
.math-root span { border-top: 1px solid currentColor; padding: 0 3px; }
.math-help { background: var(--surface-2); border: 1px solid var(--border); border-radius: 14px; padding: 12px 14px; font-size: 14px; color: var(--muted); }
.rights-help { background: #f8fafc; border: 1px solid var(--border); border-radius: 14px; padding: 13px 15px; color: var(--muted); line-height: 1.55; }
.permission-editor { display: grid; gap: 12px; background: var(--surface-2); border: 1px solid var(--border); border-radius: 16px; padding: 18px; }
.permission-editor h3 { margin: 0; }
.permission-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px 14px; }
.permission-option { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 12px; }
.form-stack { display: grid; gap: 18px; margin-top: 24px; }
.form-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.span-2 { grid-column: span 2; }
.btn { border: 0; border-radius: 12px; padding: 12px 18px; font-weight: 800; cursor: pointer; display: inline-flex; align-items: center; justify-content: center; gap: 8px; text-decoration: none; }
.btn:disabled { opacity: .55; cursor: not-allowed; }
.btn-spinner { width: 15px; height: 15px; border: 2px solid currentColor; border-right-color: transparent; border-radius: 50%; display: inline-block; animation: spin .65s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.btn-sm { padding: 8px 12px; border-radius: 10px; font-size: 13px; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); text-decoration: none; }
.btn-outline { background: #fff; border: 1px solid var(--border); color: var(--text); }
.btn-full { width: 100%; }
.alert { padding: 13px 16px; border-radius: 14px; margin-bottom: 16px; font-weight: 700; }
.alert-success { background: #ecfdf3; color: var(--success); border: 1px solid #b8eacb; }
.alert-error { background: #fff2f1; color: var(--danger); border: 1px solid #ffd0cc; }
.swal-lite-overlay { position: fixed; inset: 0; z-index: 1000; display: grid; place-items: center; padding: 24px; background: rgba(7,31,60,.42); }
.swal-lite-dialog { width: min(420px, 100%); background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 24px; box-shadow: var(--shadow); }
.swal-lite-dialog h2 { margin: 0 0 10px; font-size: 24px; }
.swal-lite-dialog p { margin: 0; color: var(--muted); line-height: 1.5; }
.swal-lite-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 22px; }
.sidebar { position: fixed; inset: 0 auto 0 0; width: 260px; max-height: 100vh; background: #071f3c; color: #fff; padding: 26px; display: flex; flex-direction: column; overflow: hidden; }
.sidebar-brand { flex: 0 0 auto; display: flex; gap: 12px; align-items: center; margin-bottom: 24px; }
.sidebar-brand span { width: 44px; height: 44px; display: grid; place-items: center; background: #fff; color: var(--primary); border-radius: 14px; font-weight: 900; }
.app-logo-mark { overflow: hidden; }
.app-logo-mark img { width: 100%; height: 100%; object-fit: contain; padding: 3px; }
.app-logo-mark img:not([hidden]) + b { display: none; }
.sidebar-nav { flex: 1 1 auto; min-height: 0; overflow-y: auto; overscroll-behavior: contain; padding-right: 4px; display: grid; align-content: start; gap: 8px; }
.sidebar-account { flex: 0 0 auto; display: grid; gap: 8px; margin-top: 16px; padding-top: 14px; border-top: 1px solid rgba(255,255,255,.16); }
.sidebar nav a { color: #dcecff; padding: 12px 14px; border-radius: 12px; font-weight: 700; }
.sidebar nav a:hover { background: rgba(255,255,255,.12); text-decoration: none; }
.sidebar-nav::-webkit-scrollbar { width: 8px; }
.sidebar-nav::-webkit-scrollbar-thumb { background: rgba(255,255,255,.24); border-radius: 999px; }
.app-shell { margin-left: 260px; min-height: 100vh; }
.topbar { height: 76px; background: #fff; border-bottom: 1px solid var(--border); display: flex; align-items: center; justify-content: space-between; padding: 0 32px; }
.topbar span { display: block; color: var(--muted); font-size: 13px; }
.content { padding: 32px; }
.page-header, .test-topbar { display: flex; justify-content: space-between; align-items: center; gap: 24px; margin-bottom: 24px; }
.page-header h1, .test-topbar h1 { margin: 0; font-size: 34px; }
.panel, .exam-card, .stat-card, .question-card { background: var(--surface); border: 1px solid var(--border); border-radius: 22px; padding: 24px; box-shadow: var(--shadow); }
.narrow { max-width: 920px; }
.stats-grid, .card-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 18px; margin-bottom: 24px; }
.card-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.stat-card span { color: var(--muted); font-weight: 700; }
.stat-card strong { display: block; font-size: 36px; margin-top: 8px; }
.stat-card .stat-text { font-size: 17px; overflow-wrap: anywhere; }
.action-grid { display: flex; gap: 14px; flex-wrap: wrap; }
.action-grid a { padding: 16px 18px; border-radius: 14px; background: var(--surface-2); font-weight: 800; }
.table-wrap { overflow-x: auto; }
.badge { display: inline-flex; border-radius: 999px; padding: 6px 10px; font-size: 12px; font-weight: 900; }
.badge-success { background: #ecfdf3; color: var(--success); }
.badge-error { background: #fff2f1; color: var(--danger); }
.badge-muted { background: var(--surface-2); color: var(--muted); }
.email-status-note { display: inline-flex; margin-left: 6px; margin-top: 6px; border-radius: 999px; padding: 5px 9px; font-size: 12px; font-weight: 900; }
.email-status-sent { background: #ecfdf3; color: var(--success); }
.email-status-failed { background: #fff2f1; color: var(--danger); }
.actions { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.actions form { display: inline; }
.link-button { background: none; border: 0; color: var(--primary); cursor: pointer; padding: 0; font-weight: 700; }
.link-button:disabled { color: var(--muted); cursor: not-allowed; }
.link-danger { background: none; border: 0; color: var(--danger); cursor: pointer; padding: 0; font-weight: 700; }
.checkbox { display: flex; gap: 8px; align-items: center; }
.checkbox input { width: auto; margin: 0; }
.form-actions { display: flex; justify-content: flex-end; gap: 12px; }
.assignment-actions { margin-top: 18px; }
.inline-check { width: auto; margin: 0; }
.card-tools { align-items: end; margin-bottom: 14px; padding-bottom: 18px; border-bottom: 1px solid var(--border); }
.email-card-form { margin-bottom: 18px; }
.card-tool-grid { display: grid; grid-template-columns: minmax(280px, 1fr) minmax(220px, auto); gap: 18px; align-items: end; margin-bottom: 20px; padding-bottom: 18px; border-bottom: 1px solid var(--border); }
.card-tool-panel { display: grid; gap: 12px; }
.card-row-actions { min-width: 360px; }
.card-row-actions, .inline-card-form { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.inline-card-form select { width: 150px; margin-top: 0; padding: 8px 10px; border-radius: 10px; }
.room-cell { min-width: 280px; }
.room-select-form { display: grid; gap: 6px; }
.room-select-form select { margin-top: 0; min-width: 250px; padding: 8px 10px; border-radius: 10px; }
.room-balance { color: var(--muted); font-size: 12px; font-weight: 800; }
.short-input { width: 88px; margin-top: 0; padding: 8px 10px; border-radius: 10px; }
.question-card { display: flex; justify-content: space-between; gap: 18px; margin-bottom: 14px; }
.option-editor { background: var(--surface-2); border-radius: 18px; padding: 18px; }
.option-row { display: grid; grid-template-columns: 24px 1fr; gap: 12px; align-items: center; margin-bottom: 10px; }
.option-row input[type="checkbox"] { width: auto; margin: 0; }
.exam-card { display: grid; gap: 18px; }
.exam-card h2 { margin: 0 0 8px; }
.meta-list, .option-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.meta-list li { background: var(--surface-2); border-radius: 12px; padding: 10px 12px; color: var(--muted); font-weight: 700; }
.exam-facts { display: flex; gap: 12px; flex-wrap: wrap; margin: 20px 0; }
.exam-facts span { padding: 12px 14px; border-radius: 14px; background: var(--surface-2); }
.timer { background: #fff; border: 1px solid var(--border); border-radius: 18px; padding: 14px 18px; box-shadow: var(--shadow); }
.timer strong { color: var(--danger); }
.question-panel { margin-bottom: 18px; }
.exam-progress-panel { display: flex; justify-content: space-between; gap: 18px; align-items: center; margin-bottom: 18px; }
.question-heading { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; }
.question-jump-list { display: flex; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
.question-jump { width: 38px; height: 38px; border: 1px solid var(--border); border-radius: 10px; background: #fff; color: var(--text); font-weight: 900; cursor: pointer; }
.question-jump.is-active { background: var(--primary); color: #fff; border-color: var(--primary); }
.question-jump.is-answered { border-color: #95d6ad; box-shadow: inset 0 -4px 0 #95d6ad; }
.question-text { font-size: 19px; line-height: 1.5; }
.question-image, .question-image-preview { display: block; width: min(720px, 100%); max-height: 430px; object-fit: contain; border: 1px solid var(--border); border-radius: 14px; background: #fff; margin: 14px 0; }
.question-image-thumb { display: block; width: min(260px, 100%); max-height: 160px; object-fit: contain; border: 1px solid var(--border); border-radius: 12px; background: #fff; margin: 10px 0; }
.answer-options { display: grid; gap: 12px; margin-top: 18px; }
.answer-option { display: flex; gap: 12px; align-items: flex-start; padding: 14px; background: var(--surface-2); border-radius: 14px; cursor: pointer; }
.answer-option input { width: auto; margin-top: 3px; }
.submit-bar { position: sticky; bottom: 0; display: flex; justify-content: flex-end; padding: 18px; background: rgba(244,247,251,.9); backdrop-filter: blur(10px); border-top: 1px solid var(--border); }
.exam-nav-bar { gap: 10px; }
.score-card { background: #fff; border: 1px solid var(--border); border-radius: 22px; padding: 18px 24px; text-align: center; box-shadow: var(--shadow); }
.score-card strong { display: block; font-size: 34px; color: var(--primary); }
.review-question { border-bottom: 1px solid var(--border); padding: 18px 0; }
.review-question:last-child { border-bottom: 0; }
.option-list li { border: 1px solid var(--border); border-radius: 14px; padding: 12px 14px; display: flex; gap: 8px; justify-content: space-between; }
.option-list li.correct { border-color: #95d6ad; background: #ecfdf3; }
.option-list li.selected { outline: 2px solid #99c7f5; }
.option-list span { font-size: 12px; font-weight: 900; color: var(--primary); }
@media (max-width: 920px) {
    .guest-shell { grid-template-columns: 1fr; }
    .brand-panel { display: none; }
    .sidebar { position: static; width: auto; max-height: none; padding: 18px; overflow: visible; }
    .sidebar-brand { margin-bottom: 14px; }
    .sidebar-nav, .sidebar-account { display: flex; overflow-x: auto; overflow-y: visible; gap: 8px; padding-bottom: 6px; }
    .sidebar-account { margin-top: 8px; padding-top: 10px; }
    .sidebar nav a { flex: 0 0 auto; white-space: nowrap; }
    .app-shell { margin-left: 0; }
    .stats-grid, .card-grid, .form-grid { grid-template-columns: 1fr; }
    .card-tool-grid { grid-template-columns: 1fr; }
    .exam-progress-panel { align-items: flex-start; flex-direction: column; }
    .question-jump-list { justify-content: flex-start; }
    .span-2 { grid-column: span 1; }
    .page-header, .test-topbar { align-items: flex-start; flex-direction: column; }
}