.app-page .page-main.sql-trainer-main {
    max-width: min(1680px, calc(100vw - 2rem));
    width: 100%;
}

.sql-trainer-page {
    background: linear-gradient(160deg, #eef2f7 0%, #f8fafc 45%, #e8edf4 100%);
    min-height: calc(100vh - 56px);
}

.sql-trainer-main {
    margin: 0 auto;
    padding: 1rem 1.5rem 2.5rem;
}

.sql-trainer-header h1 {
    margin: 0.5rem 0 0.35rem;
    font-size: 1.65rem;
    color: #1e293b;
}

.sql-trainer-intro {
    margin: 0 0 1.25rem;
    color: #475569;
    max-width: 72rem;
}

.sql-trainer-db-error {
    max-width: 72rem;
}

.sql-sandbox-notice {
    margin: 0 0 1.25rem;
    padding: 0.65rem 0.85rem;
    background: #ecfdf5;
    border: 1px solid #a7f3d0;
    border-radius: 8px;
    font-size: 0.88rem;
    color: #065f46;
    max-width: 72rem;
}

.sql-sandbox-notice strong {
    color: #047857;
}

.sql-trainer-grid {
    display: grid;
    grid-template-columns: minmax(360px, 1fr) minmax(480px, 1.45fr);
    gap: 1.5rem;
    align-items: start;
}

@media (max-width: 1100px) {
    .sql-trainer-grid {
        grid-template-columns: 1fr;
    }
}

.sql-card {
    background: #fff;
    border: 1px solid #dbe3ee;
    border-radius: 12px;
    padding: 1rem 1.1rem;
    box-shadow: 0 2px 8px rgba(15, 23, 42, 0.06);
    margin-bottom: 1rem;
}

.sql-card h2 {
    margin: 0 0 0.75rem;
    font-size: 1.05rem;
    color: #0f172a;
}

.sql-card h3 {
    margin: 0.75rem 0 0.4rem;
    font-size: 0.92rem;
    color: #334155;
}

.sql-schema-diagram {
    margin: 0;
    padding: 0.75rem;
    background: #f1f5f9;
    border-radius: 8px;
    font-size: 0.82rem;
    line-height: 1.55;
    white-space: pre-wrap;
    color: #334155;
}

.sql-table-wrap {
    overflow-x: auto;
    margin-bottom: 0.5rem;
}

.sql-data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.78rem;
}

.sql-data-table th {
    background: #1e4d8c;
    color: #fff;
    text-align: left;
    padding: 0.35rem 0.5rem;
    white-space: nowrap;
}

.sql-data-table td {
    padding: 0.3rem 0.5rem;
    border-bottom: 1px solid #e2e8f0;
}

.sql-data-table tbody tr:nth-child(even) {
    background: #f8fafc;
}

.sql-task-head {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.5rem 0.75rem;
    margin-bottom: 0.75rem;
}

.sql-task-head h2 {
    margin: 0;
    flex: 1 1 auto;
}

.sql-task-progress {
    font-size: 0.88rem;
    color: #64748b;
}

.sql-task-prompt {
    font-size: 1rem;
    line-height: 1.5;
    margin: 0 0 0.75rem;
    color: #1e293b;
}

.sql-task-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 0.75rem;
}

.sql-badge {
    display: inline-block;
    padding: 0.15rem 0.55rem;
    border-radius: 999px;
    font-size: 0.72rem;
    font-weight: 600;
}

.sql-badge-select {
    background: #e0e7ff;
    color: #3730a3;
}

.sql-badge-easy {
    background: #dcfce7;
    color: #166534;
}

.sql-badge-medium {
    background: #ffedd5;
    color: #c2410c;
}

.sql-badge-hard {
    background: #fee2e2;
    color: #b91c1c;
}

.sql-badge-expert {
    background: #ede9fe;
    color: #5b21b6;
}

.sql-hint,
.sql-solution {
    background: #f0f9ff;
    border: 1px solid #bae6fd;
    border-radius: 8px;
    padding: 0.65rem 0.75rem;
    margin-bottom: 0.75rem;
    font-size: 0.88rem;
}

.sql-solution pre {
    margin: 0.5rem 0 0;
    overflow-x: auto;
}

.sql-solution code {
    font-family: ui-monospace, 'Cascadia Code', Consolas, monospace;
    font-size: 0.82rem;
    white-space: pre-wrap;
}

.sql-task-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.sql-textarea {
    width: 100%;
    min-height: 180px;
    font-family: ui-monospace, 'Cascadia Code', Consolas, monospace;
    font-size: 0.88rem;
    padding: 0.65rem 0.75rem;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    resize: vertical;
    box-sizing: border-box;
}

.sql-input-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.65rem;
}

.btn-sql-primary,
.btn-sql-secondary {
    border-radius: 8px;
    padding: 0.45rem 0.9rem;
    font-size: 0.88rem;
    cursor: pointer;
    border: 1px solid transparent;
}

.btn-sql-primary {
    background: #1d4ed8;
    color: #fff;
}

.btn-sql-primary:hover {
    background: #1e40af;
}

.btn-sql-secondary {
    background: #f1f5f9;
    color: #334155;
    border-color: #cbd5e1;
}

.btn-sql-secondary:hover:not(:disabled) {
    background: #e2e8f0;
}

.btn-sql-secondary:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.sql-status {
    margin: 0.65rem 0 0.25rem;
    font-size: 0.88rem;
    color: #475569;
}

.sql-status-ok {
    color: #15803d;
    font-weight: 600;
}

.sql-note {
    margin: 0;
    font-size: 0.78rem;
    color: #94a3b8;
}

.sql-empty {
    color: #94a3b8;
    font-size: 0.88rem;
    margin: 0;
}

.sql-empty-cell {
    text-align: center;
    color: #94a3b8;
}

.sql-result-area {
    min-height: 6rem;
}

.sql-badge-topic {
    background: #e0f2fe;
    color: #0369a1;
}

.sql-badge-cmd {
    font-family: ui-monospace, Consolas, monospace;
    letter-spacing: 0.02em;
}

.sql-badge-cmd-select {
    background: #dbeafe;
    color: #1e40af;
}

.sql-badge-cmd-insert {
    background: #dcfce7;
    color: #166534;
}

.sql-badge-cmd-update {
    background: #fef3c7;
    color: #b45309;
}

.sql-badge-cmd-delete {
    background: #fee2e2;
    color: #b91c1c;
}

.sql-reset-db {
    margin-top: 0.75rem;
    width: 100%;
}

.sql-mutation-msg {
    margin: 0;
    padding: 0.75rem;
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    border-radius: 8px;
    color: #166534;
    font-size: 0.9rem;
}

.exam-sql-link-card {
    list-style: none;
    margin: 0;
    padding: 0;
}

.exam-sql-link-card li {
    background: #fff;
    border: 1px solid #dbe3ee;
    border-radius: 10px;
    padding: 0.85rem 1rem;
    margin-bottom: 0.5rem;
}

.exam-sql-link-card a {
    font-weight: 600;
    color: #1d4ed8;
    text-decoration: none;
}

.exam-sql-link-card a:hover {
    text-decoration: underline;
}

.quiz-tag-sql {
    display: inline-block;
    background: #dbeafe;
    color: #1e40af;
    font-size: 0.72rem;
    font-weight: 600;
    padding: 0.1rem 0.45rem;
    border-radius: 4px;
    margin-right: 0.35rem;
}