:root {
    --primary: #2c3e50;
    --accent: #3498db;
    --bg: #f4f6f8;
    --card: #ffffff;
    --border: #dbe2e8;
    --error: #c0392b;
    --text: #333333;
    --muted: #666666;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 1rem;
}

.card {
    background: var(--card);
    border-radius: 0.5rem;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    margin-bottom: 1rem;
}

.center {
    text-align: center;
}

h1 {
    font-size: 1.5rem;
    margin: 0 0 0.75rem;
    color: var(--primary);
}

h2 {
    font-size: 1.1rem;
    color: var(--primary);
    border-bottom: 1px solid var(--border);
    padding-bottom: 0.5rem;
    margin-top: 1.5rem;
}

.intro {
    color: var(--muted);
    margin-bottom: 1.25rem;
}

.actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin: 1.5rem 0;
}

.btn {
    display: inline-block;
    background-color: var(--accent);
    color: white;
    text-decoration: none;
    padding: 0.85rem 1.25rem;
    border-radius: 0.35rem;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    text-align: center;
    transition: background 0.2s ease;
}

.btn:hover {
    background-color: #2980b9;
}

.note {
    font-size: 0.85rem;
    color: var(--muted);
    margin-top: 1rem;
}

.error {
    color: white;
    background-color: var(--error);
    padding: 0.75rem;
    border-radius: 0.35rem;
    margin: 0 0 1rem;
}

.demographics .field-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.field-group {
    margin-bottom: 0.5rem;
}

.field-label {
    display: block;
    font-size: 0.95rem;
    margin-bottom: 0.25rem;
}

.demographics label,
.item label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.demographics input[type="text"],
.demographics input[type="number"] {
    width: 100%;
    padding: 0.55rem;
    font-size: 1rem;
    border: 1px solid var(--border);
    border-radius: 0.25rem;
    margin-top: 0.25rem;
}

.items {
    margin-top: 1.5rem;
}

.item {
    padding: 1rem 0;
    border-bottom: 1px solid var(--border);
}

.item:last-child {
    border-bottom: none;
}

.item-text {
    font-size: 1rem;
    margin: 0 0 0.25rem;
}

.dimension {
    font-size: 0.8rem;
    color: var(--muted);
    margin: 0 0 0.75rem;
}

.options {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.option {
    flex: 1 1 8rem;
    min-width: 6rem;
    border: 1px solid var(--border);
    border-radius: 0.35rem;
    padding: 0.5rem;
    text-align: center;
    cursor: pointer;
    background: #fafbfc;
    transition: border-color 0.15s, background 0.15s;
}

.option input {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.option span {
    display: block;
    font-size: 0.9rem;
}

.option .label-text {
    font-size: 0.75rem;
    color: var(--muted);
}

.option input:checked + span,
.option:has(input:checked) {
    border-color: var(--accent);
    background: #eaf4fc;
}

.option:has(input:checked) .label-text {
    color: var(--accent);
}

.submit-row {
    margin-top: 1.5rem;
    text-align: center;
}

.submit-row .btn {
    width: 100%;
    font-size: 1.1rem;
}

.response-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
    margin-top: 1rem;
}

.response-table th,
.response-table td {
    border: 1px solid var(--border);
    padding: 0.5rem;
    text-align: left;
}

.response-table th {
    background: #f0f3f6;
    color: var(--primary);
}

.back {
    margin-top: 1rem;
    text-align: center;
}

.stats {
    display: flex;
    gap: 1rem;
    margin: 1rem 0;
    flex-wrap: wrap;
}

.stat-box {
    flex: 1 1 8rem;
    background: #f0f3f6;
    border: 1px solid var(--border);
    border-radius: 0.35rem;
    padding: 1rem;
    text-align: center;
}

.stat-value {
    display: block;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary);
}

.stat-label {
    display: block;
    font-size: 0.85rem;
    color: var(--muted);
    margin-top: 0.25rem;
}

.stat-list {
    list-style: none;
    padding: 0;
    margin: 0 0 1rem;
}

.stat-list li {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border);
}

.stat-list li:last-child {
    border-bottom: none;
}

.admin-wrap {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
}

.admin-sidebar {
    flex: 0 0 220px;
}

.admin-main {
    flex: 1 1 0;
    min-width: 0;
}

.sidebar-card {
    padding: 1rem;
}

.admin-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.admin-nav a {
    display: block;
    padding: 0.6rem 0.75rem;
    border-radius: 0.35rem;
    text-decoration: none;
    color: var(--text);
    border: 1px solid var(--border);
    background: #fafbfc;
    font-size: 0.95rem;
}

.admin-nav a:hover,
.admin-nav a.active {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
}

.admin-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin: 1rem 0;
}

.panel {
    background: #f8fafb;
    border: 1px solid var(--border);
    border-radius: 0.35rem;
    padding: 1rem;
}

.panel h2 {
    margin-top: 0;
    font-size: 1rem;
    border-bottom: none;
    padding-bottom: 0;
    color: var(--primary);
}

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

.table-wrap .response-table {
    min-width: 600px;
}

@media (max-width: 768px) {
    .container {
        padding: 0.5rem;
    }

    .card {
        padding: 1rem;
    }

    h1 {
        font-size: 1.3rem;
    }

    .admin-wrap {
        flex-direction: column;
    }

    .admin-sidebar {
        flex: 1 1 auto;
        width: 100%;
    }

    .admin-main {
        width: 100%;
    }

    .admin-nav {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .admin-nav a {
        flex: 1 1 auto;
    }

    .demographics .field-row {
        grid-template-columns: 1fr;
    }

    .options {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
    }

    .option {
        min-width: 0;
    }
}

@media (max-width: 480px) {
    .options {
        grid-template-columns: repeat(2, 1fr);
    }
}