:root {
    --cn-bg: #F2EDE3;
    --cn-surface: #FBF8F1;
    --cn-surface-2: #F1E9DA;
    --cn-desk: #E6DFD2;
    --cn-line: #DED5C5;
    --cn-line-2: #CFC5B4;
    --cn-ink: #3E2C23;
    --cn-ink-2: #4A3728;
    --cn-ink-3: #8A7A6A;
    --cn-ink-4: #6E6152;
    --cn-cinnabar: #C8102E;
    --cn-cinnabar-2: #A50D25;
    --cn-dai: #2E4A62;
    --cn-brass: #C9A227;
    --radius: 12px;
    --font: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC",
        "Helvetica Neue", Arial, sans-serif;
    --seal-grad: linear-gradient(135deg, #d3142f, var(--cn-cinnabar-2));
}

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

body {
    background:
        radial-gradient(circle at 10% -8%, rgba(200, 16, 46, 0.055), transparent 42%),
        radial-gradient(circle at 92% -4%, rgba(46, 74, 98, 0.05), transparent 38%),
        var(--cn-bg);
    color: var(--cn-ink);
    font-family: var(--font);
    font-size: 16.5px;
    line-height: 1.95;
    padding: 0 18px;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--cn-cinnabar); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: 900px; margin: 0 auto; }

/* ---------- 顶栏 ---------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 10;
    background: rgba(242, 237, 227, 0.88);
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--cn-line);
}
.site-header .wrap {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    padding: 13px 2px;
}
.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 17px;
    font-weight: 700;
    letter-spacing: 2px;
    color: var(--cn-ink);
    text-decoration: none;
}
.brand:hover { text-decoration: none; }
.brand .seal {
    width: 30px;
    height: 30px;
    display: grid;
    place-items: center;
    background: var(--seal-grad);
    color: #fff;
    border-radius: 8px;
    font-size: 15px;
    letter-spacing: 0;
    box-shadow: 0 2px 8px rgba(200, 16, 46, 0.35);
}
.site-nav { display: flex; align-items: center; }
.site-nav a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: var(--cn-ink-4);
    margin-left: 20px;
    padding-bottom: 2px;
    border-bottom: 2px solid transparent;
    transition: color 0.15s, border-color 0.15s;
}
.site-nav a:hover { color: var(--cn-cinnabar); border-bottom-color: var(--cn-cinnabar); text-decoration: none; }
.site-nav a::before {
    content: '';
    width: 15px;
    height: 15px;
    background: currentColor;
    -webkit-mask: var(--icon) center / contain no-repeat;
    mask: var(--icon) center / contain no-repeat;
}
.site-nav a:nth-child(1) {
    --icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M3 17.25V21h3.75L17.81 9.94l-3.75-3.75L3 17.25zM20.71 7.04a1 1 0 0 0 0-1.41l-2.34-2.34a1 1 0 0 0-1.41 0l-1.83 1.83 3.75 3.75 1.83-1.83z'/%3E%3C/svg%3E");
}
.site-nav a:nth-child(2) {
    --icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M18 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V4a2 2 0 0 0-2-2zM6 4h5v8l-2.5-1.5L6 12V4z'/%3E%3C/svg%3E");
}

/* ---------- 纸面卡片 ---------- */
main.wrap {
    position: relative;
    overflow: hidden;
    margin: 30px auto 0;
    background: var(--cn-surface);
    border: 1px solid var(--cn-line);
    border-radius: var(--radius);
    box-shadow: 0 18px 44px rgba(62, 44, 35, 0.11);
    padding: 52px 60px 48px;
}
main.wrap::before {
    content: '';
    position: absolute;
    inset: 0 0 auto 0;
    height: 4px;
    background: linear-gradient(90deg, var(--cn-cinnabar), var(--cn-brass) 55%, var(--cn-dai));
}

/* ---------- 标题与正文 ---------- */
h1.article-title {
    font-size: 29px;
    line-height: 1.5;
    font-weight: 800;
    letter-spacing: 0.5px;
    color: var(--cn-ink);
}
h1.article-title::after {
    content: '';
    display: block;
    width: 66px;
    height: 4px;
    margin-top: 16px;
    border-radius: 3px;
    background: linear-gradient(90deg, var(--cn-cinnabar), rgba(200, 16, 46, 0));
}
.article-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--cn-ink-3);
    font-size: 13.5px;
    margin: 20px 0 26px;
    padding-bottom: 20px;
    border-bottom: 1px dashed var(--cn-line);
}
.article-meta::before {
    content: '';
    width: 7px;
    height: 7px;
    background: var(--cn-cinnabar);
    border-radius: 2px;
    transform: rotate(45deg);
}
.page-intro { color: var(--cn-ink-4); margin-bottom: 6px; }

article h2 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.5px;
    margin: 38px 0 14px;
    color: var(--cn-ink);
}
article h2::before {
    content: '';
    flex: none;
    width: 14px;
    height: 14px;
    border-radius: 4px;
    background: var(--seal-grad);
    box-shadow: 0 2px 6px rgba(200, 16, 46, 0.3);
}
article h3 { font-size: 17px; font-weight: 700; color: var(--cn-ink-2); margin: 24px 0 8px; }
article p { margin-bottom: 16px; }
article ul { list-style: none; margin: 0 0 16px; }
article ul li { position: relative; padding-left: 22px; margin: 8px 0; }
article ul li::before {
    content: '';
    position: absolute;
    left: 2px;
    top: 0.72em;
    width: 7px;
    height: 7px;
    background: var(--cn-cinnabar);
    border-radius: 2px;
    transform: rotate(45deg);
    opacity: 0.9;
}
article ol { margin: 0 0 16px; padding-left: 22px; }
article ol li { margin: 8px 0; padding-left: 4px; }
article ol li::marker { color: var(--cn-cinnabar); font-weight: 700; }
article strong { color: var(--cn-ink); }
article img { max-width: 100%; border: 1px solid var(--cn-line); border-radius: 8px; }
article blockquote {
    margin: 0 0 18px;
    padding: 12px 18px;
    background: var(--cn-surface-2);
    border-left: 3px solid var(--cn-cinnabar);
    border-radius: 0 8px 8px 0;
    color: var(--cn-ink-4);
}

/* ---------- 博客索引（卡片） ---------- */
.post-list { list-style: none; margin: 0; display: grid; gap: 14px; }
.post-list li {
    position: relative;
    padding: 20px 24px;
    background: var(--cn-surface-2);
    border: 1px solid var(--cn-line);
    border-radius: 10px;
    transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}
.post-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 15px;
    bottom: 15px;
    width: 3px;
    border-radius: 0 3px 3px 0;
    background: var(--cn-cinnabar);
}
.post-list li:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 26px rgba(62, 44, 35, 0.13);
    border-color: var(--cn-line-2);
}
.post-link { display: block; font-size: 18px; font-weight: 700; color: var(--cn-ink); }
.post-link::after {
    content: '→';
    margin-left: 6px;
    color: var(--cn-cinnabar);
    opacity: 0;
    transition: opacity 0.18s, margin-left 0.18s;
}
.post-list li:hover .post-link::after { opacity: 1; margin-left: 10px; }
.post-list li:hover .post-link { text-decoration: none; }
.post-excerpt { color: var(--cn-ink-4); font-size: 14.5px; margin-top: 6px; }

/* ---------- CTA ---------- */
.cta {
    margin: 40px 0 8px;
    padding: 26px;
    text-align: center;
    background: linear-gradient(180deg, var(--cn-surface-2), #ECE1CE);
    border: 1px solid var(--cn-line);
    border-radius: 12px;
}
.cta p { color: var(--cn-ink-4); font-size: 15px; margin-bottom: 16px; }
.cta .btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    background: var(--seal-grad);
    color: #fff;
    font-weight: 600;
    letter-spacing: 1px;
    border-radius: 9px;
    box-shadow: 0 8px 18px rgba(200, 16, 46, 0.28);
    transition: transform 0.15s, box-shadow 0.15s;
}
.cta .btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 12px 24px rgba(200, 16, 46, 0.36);
    text-decoration: none;
}

.breadcrumb {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: var(--cn-ink-3);
    margin-bottom: 18px;
}
.breadcrumb a { color: var(--cn-ink-3); }
.breadcrumb a:hover { color: var(--cn-cinnabar); text-decoration: none; }

.site-footer {
    margin-top: 30px;
    padding: 22px 0 42px;
    color: var(--cn-ink-3);
    font-size: 13px;
    text-align: center;
}
.site-footer a { color: var(--cn-ink-3); }
.site-footer a:hover { color: var(--cn-cinnabar); }

@media (max-width: 680px) {
    body { font-size: 16px; line-height: 1.9; }
    main.wrap { padding: 34px 22px 30px; margin-top: 20px; }
    h1.article-title { font-size: 24px; }
    article h2 { font-size: 18.5px; }
    .site-header .wrap { flex-direction: column; align-items: flex-start; gap: 8px; }
    .site-nav a { margin-left: 0; margin-right: 18px; }
}