:root {
    --cy-accent: #ff5a1f;
    --cy-accent-strong: #e64910;
    --cy-accent-soft: #fff1ea;
    --cy-bg: #f6f6f4;
    --cy-surface: #ffffff;
    --cy-surface-soft: #faf8f6;
    --cy-border: #ebe5df;
    --cy-text: #1f1a17;
    --cy-soft: #5e5650;
    --cy-muted: #92877d;
    --cy-shadow: 0 10px 24px rgba(31, 26, 23, 0.06);
    --cy-title-font: "Songti SC", "STSong", "Noto Serif SC", "Source Han Serif SC", "SimSun", serif;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    background: var(--cy-bg);
    color: var(--cy-text);
    font: 14px/1.75 -apple-system, BlinkMacSystemFont, "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

a {
    color: inherit;
    text-decoration: none;
}

.page-shell {
    padding: 14px 0 28px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    color: var(--cy-muted);
    font-size: 12px;
}

.breadcrumb a {
    color: var(--cy-soft);
}

.hero-card,
.panel {
    background: var(--cy-surface);
    border: 1px solid var(--cy-border);
    border-radius: 16px;
    box-shadow: var(--cy-shadow);
}

.hero-card,
.panel {
    padding: 18px;
}

.hero-card h1,
.panel-head h2,
.pattern-card h3,
.letter-card strong,
.category-card strong,
.feature-word {
    margin: 0;
    color: var(--cy-text);
    font-family: var(--cy-title-font);
}

.hero-card h1 {
    font-size: 32px;
    line-height: 1.18;
}

.hero-card p,
.feature-card p,
.pattern-card p {
    margin: 10px 0 0;
    color: var(--cy-soft);
    line-height: 1.8;
}

.panel {
    margin-top: 14px;
}

.panel-head {
    margin-bottom: 14px;
}

.panel-head h2 {
    font-size: 24px;
    line-height: 1.2;
}

.letter-grid,
.category-grid,
.pattern-grid,
.feature-grid {
    display: grid;
    gap: 10px;
}

.letter-grid {
    grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
}

.category-grid,
.feature-grid {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.pattern-grid {
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.letter-card,
.category-card,
.pattern-card,
.feature-card {
    display: block;
    padding: 14px;
    border-radius: 12px;
    background: var(--cy-surface-soft);
}

.letter-card strong {
    display: block;
    font-size: 28px;
    line-height: 1;
}

.letter-card span,
.category-card span,
.pattern-code,
.feature-pinyin {
    color: var(--cy-muted);
    font-size: 12px;
}

.category-card strong,
.feature-word,
.pattern-card h3 {
    display: block;
    font-size: 22px;
    line-height: 1.2;
}

.pattern-code {
    display: inline-flex;
    align-items: center;
    min-height: 24px;
    padding: 0 10px;
    border-radius: 999px;
    background: var(--cy-accent-soft);
    color: var(--cy-accent-strong);
    font-weight: 700;
}

.pattern-card strong {
    display: block;
    margin-top: 8px;
    color: var(--cy-text);
    font-size: 14px;
}

.feature-pinyin {
    margin-top: 6px;
}

.letter-card:hover,
.category-card:hover,
.pattern-card:hover,
.feature-card:hover {
    background: var(--cy-accent-soft);
}

@media (max-width: 640px) {
    .page-shell {
        padding: 10px 0 22px;
    }

    .container {
        padding: 0 12px;
    }

    .hero-card,
    .panel {
        padding: 14px 12px;
    }

    .hero-card h1,
    .panel-head h2 {
        font-size: 24px;
    }
}