:root {
    --fg: #0f172a;
    --muted: #475569;
    --bg: #ffffff;
    --accent: #0ea5e9;
    --border: #e2e8f0;
}

li a {
    color: blue;
}

h1 {
    font-size: 2rem;
    margin: 0 0 0.5rem;
}

.stand {
    color: var(--muted);
    margin-bottom: 1.5rem;
}

.structure {
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1rem;
    margin: 1.5rem 0 2rem;
    background: #fafafa;
}

section {
    margin: 2.25rem 0;
}

.note {
    color: var(--muted);
    font-size: 0.95rem;
}

ul,
ol {
    padding-left: 1.25rem;
}

.small {
    font-size: .95rem;
}

details {
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: .75rem 1rem;
    background: #fcfcfc;
}

details+details {
    margin-top: .75rem;
}

.title {
    font-size: 2rem;
}

@media (max-width: 400px) {
    .title {
        font-size: 1.5rem;
    }

    h2 {
        font-size: 1.25rem;
    }
}


.table-responsive {
    width: 100%;
    overflow-x: auto;
}

.retention {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    font-size: 1rem;
}

.retention th,
.retention td {
    border: 1px solid var(--border, #e2e8f0);
    padding: 0.5rem 0.75rem;
    text-align: left;
}

.retention th {
    background: #f3f4f6;
    font-weight: 600;
}

@media (max-width: 700px) {
    .retention thead {
        display: none;
    }

    .retention,
    .retention tbody,
    .retention tr,
    .retention td {
        display: block;
        width: 100%;
    }

    .retention tr {
        margin-bottom: 1.25rem;
        border-bottom: 2px solid var(--border, #e2e8f0);
    }

    .retention td {
        border: none;
        border-bottom: 1px solid var(--border, #e2e8f0);
        position: relative;
        padding-left: 50%;
        min-height: 2.5rem;
    }

    .retention td:before {
        position: absolute;
        top: 0;
        left: 0;
        width: 48%;
        padding-left: 0.75rem;
        font-weight: 600;
        white-space: nowrap;
        content: attr(data-label);
        color: var(--muted, #475569);
    }
}