:root {
    --bg: #f4f6fb;
    --surface: #ffffff;
    --text: #152236;
    --muted: #5f6b7a;
    --primary: #0a5d8f;
    --primary-soft: #e3f0f8;
    --danger: #8f2f2f;
    --danger-soft: #fbe8e8;
    --success: #216f43;
    --success-soft: #e5f7ee;
    --border: #d8dee7;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    background:
        radial-gradient(circle at 15% 10%, #ddeaf6 0, transparent 22%),
        radial-gradient(circle at 85% 0%, #eef5ff 0, transparent 28%),
        var(--bg);
    color: var(--text);
    font-family: "Segoe UI", "Trebuchet MS", "Liberation Sans", sans-serif;
    line-height: 1.4;
}

.container {
    max-width: 1100px;
    margin: 20px auto;
    padding: 0 14px 28px;
}

.narrow {
    max-width: 540px;
}

.page-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px 14px;
    margin-bottom: 14px;
}

.page-header h1 {
    margin: 0;
    margin-right: auto;
    font-size: 1.7rem;
}

.meta {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 6px 10px;
}

.lead {
    color: var(--muted);
}

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 14px;
    margin-bottom: 14px;
    box-shadow: 0 8px 24px rgba(21, 34, 54, 0.05);
}

.stack > * {
    margin-top: 0;
    margin-bottom: 10px;
}

.stack > *:last-child {
    margin-bottom: 0;
}

label {
    font-weight: 600;
}

input[type="text"],
input[type="password"],
input[type="number"],
select {
    width: 100%;
    max-width: 360px;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 8px 10px;
    font: inherit;
}

button {
    border: none;
    border-radius: 10px;
    padding: 10px 14px;
    font: inherit;
    font-weight: 600;
    background: var(--primary);
    color: #fff;
    cursor: pointer;
}

button.secondary {
    background: #476784;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.alert {
    border-radius: 10px;
    padding: 10px 12px;
    margin-bottom: 12px;
    border: 1px solid transparent;
}

.alert.error {
    background: var(--danger-soft);
    color: var(--danger);
    border-color: #e9c4c4;
}

.alert.success {
    background: var(--success-soft);
    color: var(--success);
    border-color: #b4e3c7;
}

.muted {
    color: var(--muted);
}

.muted-list,
.muted-list li {
    color: var(--muted);
}

.briefing-figure {
    margin: 0;
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    background: #fff;
}

.briefing-figure img {
    display: block;
    width: 100%;
    height: auto;
}

.briefing-figure figcaption {
    border-top: 1px solid var(--border);
    padding: 10px 12px;
    font-size: 0.95rem;
    color: var(--muted);
    background: #f9fbff;
}

.point-zero {
    color: #a3adbb;
}

.point-nonzero {
    color: var(--text);
    font-weight: 600;
}

.table-wrap {
    overflow-x: auto;
}

.desktop-label {
    display: inline;
}

.mobile-label {
    display: none;
}

.me-row {
    background: #eef6ff;
}

.components-mobile {
    display: none;
}

.component-line {
    padding: 9px 10px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: #fbfcff;
}

table {
    width: 100%;
    border-collapse: collapse;
    min-width: 700px;
}

th,
td {
    border: 1px solid var(--border);
    padding: 8px 9px;
    text-align: left;
    vertical-align: top;
}

th {
    background: var(--primary-soft);
}

.final-leaderboard-wrap table {
    min-width: 0 !important;
    table-layout: fixed;
}

.final-leaderboard-wrap th:nth-child(1),
.final-leaderboard-wrap td:nth-child(1) {
    width: 11%;
    text-align: center;
}

.final-leaderboard-wrap th:nth-child(2),
.final-leaderboard-wrap td:nth-child(2) {
    width: 33%;
    white-space: normal;
    word-break: break-word;
    overflow-wrap: anywhere;
}

.final-leaderboard-wrap th:nth-child(3),
.final-leaderboard-wrap td:nth-child(3),
.final-leaderboard-wrap th:nth-child(4),
.final-leaderboard-wrap td:nth-child(4),
.final-leaderboard-wrap th:nth-child(5),
.final-leaderboard-wrap td:nth-child(5) {
    width: 18.5%;
}

.checkbox-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 8px 10px;
}

.check-item {
    display: flex;
    gap: 8px;
    align-items: flex-start;
    padding: 8px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: #fbfcff;
}

.check-item input {
    margin-top: 2px;
}

.tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 12px;
}

.tab {
    text-decoration: none;
    color: var(--primary);
    border: 1px solid var(--border);
    background: #fff;
    border-radius: 999px;
    padding: 7px 12px;
    font-weight: 600;
}

.tab.active {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}

.inline-form {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}

.teacher-login-form .form-field {
    width: 100%;
}

.teacher-login-form label {
    display: block;
    margin-bottom: 6px;
}

.teacher-login-form .captcha-hint {
    margin: 0 0 6px;
    font-weight: 600;
    color: var(--text);
}

.teacher-login-form input[type="password"],
.teacher-login-form input[type="text"] {
    display: block;
    width: 100%;
    max-width: 100%;
}

.teacher-login-form button {
    display: inline-block;
    align-self: flex-start;
}

@media (max-width: 768px) {
    .container {
        margin: 12px auto;
        padding: 0 10px 20px;
    }

    table {
        min-width: 560px;
    }
}

@media (max-width: 640px) {
    .components-table {
        display: none;
    }

    .components-mobile {
        display: grid;
        gap: 8px;
    }

    .final-leaderboard-wrap th,
    .final-leaderboard-wrap td {
        padding: 6px 4px;
        font-size: 0.84rem;
    }

    .final-leaderboard-wrap .desktop-label {
        display: none;
    }

    .final-leaderboard-wrap .mobile-label {
        display: inline;
    }
}