/* Clean layout shared by the homepage, catalog, and tool pages. */
:root {
    --bg: #f4f6f9;
    --card: #ffffff;
    --text: #1b2430;
    --muted: #5c6b7e;
    --line: #e3e8ef;
    --accent: #2563eb;
    --accent-dark: #1d4ed8;
    --soft: #eef4ff;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Segoe UI", "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
}

a {
    color: var(--accent);
}

.topbar {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 255, 255, 0.94);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(10px);
}

.bar-inner,
.wrap {
    width: min(1080px, calc(100% - 32px));
    margin: 0 auto;
}

.bar-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    min-height: 64px;
}

.brand {
    color: var(--text);
    text-decoration: none;
    font-weight: 700;
    font-size: 1.05rem;
    letter-spacing: 0;
}

.nav {
    display: flex;
    gap: 8px;
}

.nav a {
    color: var(--muted);
    text-decoration: none;
    font-size: 0.95rem;
    padding: 8px 12px;
    border-radius: 8px;
}

.nav a:hover,
.nav a[aria-current="page"] {
    color: var(--text);
    background: var(--soft);
}

.wrap {
    padding: 28px 0 12px;
}

.panel {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 16px;
    padding: 28px;
    box-shadow: 0 1px 2px rgba(16, 24, 40, 0.04);
}

.hero {
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) minmax(240px, 0.7fr);
    gap: 28px;
    align-items: center;
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 16px;
    margin-top: 28px;
    margin-bottom: 28px;
    padding: 36px;
}

.kicker {
    color: var(--accent);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 8px;
}

h1 {
    font-size: clamp(1.8rem, 3vw, 2.4rem);
    line-height: 1.25;
    letter-spacing: 0;
    font-weight: 700;
    margin-bottom: 12px;
}

.lead,
.group-lead {
    color: var(--muted);
    max-width: 42rem;
}

.actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 22px;
}

.btn,
button,
.btn-row .btn {
    font-family: inherit;
    font-size: 0.95rem;
    color: var(--text);
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 10px;
    padding: 10px 16px;
    text-decoration: none;
    display: inline-block;
    cursor: pointer;
    line-height: 1.4;
}

.btn:hover,
button:hover {
    border-color: #c9d4e3;
    background: #f8fafc;
}

.btn.primary,
button.primary {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

.btn.primary:hover,
button.primary:hover {
    background: var(--accent-dark);
}

button:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.quick {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2px 16px;
    background: var(--soft);
    border-radius: 12px;
    padding: 16px 18px 12px;
}

.quick p {
    grid-column: 1 / -1;
    color: var(--muted);
    font-size: 0.82rem;
    font-weight: 600;
    margin-bottom: 6px;
}

.quick a {
    color: var(--text);
    text-decoration: none;
    padding: 6px 0;
    font-size: 0.95rem;
}

.quick a:hover {
    color: var(--accent);
}

.group + .group {
    margin-top: 28px;
}

.group h2,
.notes h2 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 6px;
}

.group-lead {
    margin-bottom: 14px;
    font-size: 0.95rem;
}

.cards {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
}

.card {
    display: flex;
    gap: 14px;
    align-items: flex-start;
    padding: 16px;
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 14px;
    text-decoration: none;
    color: inherit;
    min-height: 108px;
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.card:hover {
    border-color: #b9cdfb;
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.08);
}

.mark {
    flex: none;
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 10px;
    background: var(--soft);
    color: var(--accent);
    font-family: ui-monospace, Consolas, monospace;
    font-size: 0.92rem;
}

.card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.card p {
    color: var(--muted);
    font-size: 0.92rem;
    line-height: 1.55;
}

.notes {
    margin-top: 16px;
}

.note-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
    margin-top: 14px;
}

.note-list li {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 16px;
}

.note-list h3 {
    font-size: 0.98rem;
    margin-bottom: 6px;
}

.note-list p {
    color: var(--muted);
    font-size: 0.92rem;
}

.site-footer {
    margin-top: 28px;
    padding: 22px 0 32px;
    color: var(--muted);
    font-size: 0.88rem;
    text-align: center;
}

.page-lead {
    color: var(--muted);
    margin: -4px 0 22px;
}

.error-panel {
    max-width: 520px;
    margin: 48px auto;
    text-align: center;
}

.error-panel .actions {
    justify-content: center;
}

.card:focus-visible,
.btn:focus-visible,
button:focus-visible,
.nav a:focus-visible,
.brand:focus-visible,
.quick a:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

@media (max-width: 800px) {
    .hero,
    .cards,
    .note-list {
        grid-template-columns: 1fr;
    }

    .hero,
    .panel {
        padding: 22px;
    }
}