/* ============================================================
   小白博客 xiaobai.css · 孤岛模块独立样式
   双主题：html(默认) = 雅致莫兰迪(明) / html.xb-dark = 现代科技(暗)
   完全自写，不依赖任何框架 CSS
   ============================================================ */

/* ---------- 主题变量 ---------- */
:root {
    --xb-bg: #f4f1ec;
    --xb-bg-grad-a: #f6f3ee;
    --xb-bg-grad-b: #ece6dd;
    --xb-card: #fbf9f6;
    --xb-text: #45423e;
    --xb-text-2: #8f8880;
    --xb-accent: #a8917c;
    --xb-accent-deep: #8f7660;
    --xb-accent-soft: #ede3d8;
    --xb-border: #e5dfd6;
    --xb-shadow: 0 8px 28px rgba(96, 82, 68, 0.09);
    --xb-shadow-hover: 0 14px 36px rgba(96, 82, 68, 0.14);
}

html.xb-dark {
    --xb-bg: #0e1116;
    --xb-bg-grad-a: #10141b;
    --xb-bg-grad-b: #0b0e13;
    --xb-card: #171c24;
    --xb-text: #d7dce4;
    --xb-text-2: #7d8694;
    --xb-accent: #4da3ff;
    --xb-accent-deep: #7ab8ff;
    --xb-accent-soft: #1a2634;
    --xb-border: #242c37;
    --xb-shadow: 0 8px 28px rgba(0, 0, 0, 0.45);
    --xb-shadow-hover: 0 14px 36px rgba(0, 0, 0, 0.55);
}

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

html.xb-dark { color-scheme: dark; }

.xb-body {
    font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system, sans-serif;
    background: linear-gradient(160deg, var(--xb-bg-grad-a) 0%, var(--xb-bg-grad-b) 100%);
    background-attachment: fixed;
    color: var(--xb-text);
    min-height: 100vh;
    line-height: 1.7;
    transition: background 0.35s ease, color 0.35s ease;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; }

.xb-wrap {
    max-width: 860px;
    margin: 0 auto;
    padding: 56px 20px 40px;
}

.xb-wrap-narrow { max-width: 760px; }

/* ---------- 主题切换按钮（太阳/月亮） ---------- */
.xb-theme-toggle {
    position: fixed;
    top: 22px;
    right: 22px;
    z-index: 100;
    width: 46px;
    height: 46px;
    border-radius: 50%;
    border: 1px solid var(--xb-border);
    background: var(--xb-card);
    color: var(--xb-accent);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--xb-shadow);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.35s ease, color 0.35s ease;
}
.xb-theme-toggle:hover {
    transform: rotate(18deg) scale(1.06);
    box-shadow: var(--xb-shadow-hover);
}
.xb-theme-toggle:active { transform: scale(0.94); }

/* 明亮时显示月亮（点击去暗色），暗色时显示太阳 */
.xb-theme-toggle .xb-icon-sun { display: none; }
html.xb-dark .xb-theme-toggle .xb-icon-sun { display: block; }
html.xb-dark .xb-theme-toggle .xb-icon-moon { display: none; }

/* ---------- 刊头 ---------- */
.xb-hero {
    text-align: center;
    padding: 40px 0 52px;
}
.xb-hero-emoji {
    font-size: 52px;
    line-height: 1;
    margin-bottom: 18px;
}
.xb-hero-name {
    font-size: 40px;
    font-weight: 700;
    letter-spacing: 2px;
    color: var(--xb-text);
}
.xb-hero-sign {
    margin-top: 12px;
    font-size: 15px;
    color: var(--xb-text-2);
    letter-spacing: 1px;
}

/* ---------- 文章卡片流 ---------- */
.xb-list { display: flex; flex-direction: column; gap: 22px; }

.xb-card {
    background: var(--xb-card);
    border: 1px solid var(--xb-border);
    border-radius: 18px;
    overflow: hidden;
    box-shadow: var(--xb-shadow);
    transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.35s ease, border-color 0.35s ease;
}
.xb-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--xb-shadow-hover);
}

.xb-card-link { display: block; }

.xb-card-cover {
    width: 100%;
    aspect-ratio: 21 / 9;
    overflow: hidden;
    background: var(--xb-accent-soft);
}
.xb-card-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s ease;
}
.xb-card:hover .xb-card-cover img { transform: scale(1.03); }

.xb-card-body { padding: 24px 28px 22px; }

.xb-card-title {
    font-size: 21px;
    font-weight: 700;
    line-height: 1.5;
    color: var(--xb-text);
    transition: color 0.2s ease;
}
.xb-card:hover .xb-card-title { color: var(--xb-accent-deep); }

.xb-card-summary {
    margin-top: 10px;
    font-size: 14.5px;
    color: var(--xb-text-2);
    line-height: 1.8;
}

.xb-card-meta {
    margin-top: 14px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
    font-size: 13px;
    color: var(--xb-text-2);
}
.xb-meta-tag {
    color: var(--xb-accent);
    background: var(--xb-accent-soft);
    padding: 2px 10px;
    border-radius: 999px;
    font-size: 12.5px;
}

/* ---------- 空状态 ---------- */
.xb-empty {
    text-align: center;
    padding: 80px 0;
}
.xb-empty-emoji { font-size: 54px; margin-bottom: 16px; }
.xb-empty-text { color: var(--xb-text-2); font-size: 15px; }

/* ---------- 分页 ---------- */
.xb-page {
    margin-top: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 18px;
}
.xb-page-btn {
    padding: 9px 20px;
    border-radius: 999px;
    border: 1px solid var(--xb-border);
    background: var(--xb-card);
    color: var(--xb-text);
    font-size: 14px;
    transition: all 0.2s ease;
}
.xb-page-btn:hover {
    color: #fff;
    background: var(--xb-accent);
    border-color: var(--xb-accent);
}
.xb-page-info { font-size: 13.5px; color: var(--xb-text-2); }

/* ---------- 详情页 ---------- */
.xb-post {
    background: var(--xb-card);
    border: 1px solid var(--xb-border);
    border-radius: 20px;
    padding: 40px 44px;
    box-shadow: var(--xb-shadow);
    transition: background 0.35s ease, border-color 0.35s ease;
}

.xb-post-title {
    font-size: 30px;
    font-weight: 700;
    line-height: 1.5;
    letter-spacing: 0.5px;
}

.xb-post-meta {
    margin-top: 16px;
    padding-bottom: 22px;
    border-bottom: 1px dashed var(--xb-border);
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
    font-size: 13.5px;
    color: var(--xb-text-2);
}

.xb-post-cover {
    margin-top: 26px;
    border-radius: 14px;
    overflow: hidden;
}
.xb-post-cover img { width: 100%; display: block; }

/* ---------- 富文本正文托管（图/音/视频/排版全适配） ---------- */
.xb-content { margin-top: 30px; font-size: 16px; line-height: 1.95; word-break: break-word; }
.xb-content p { margin: 0 0 18px; }
.xb-content h1, .xb-content h2, .xb-content h3, .xb-content h4 {
    margin: 32px 0 16px;
    font-weight: 700;
    line-height: 1.5;
    color: var(--xb-text);
}
.xb-content h1 { font-size: 26px; }
.xb-content h2 { font-size: 22px; }
.xb-content h3 { font-size: 19px; }
.xb-content h4 { font-size: 17px; }

.xb-content img {
    display: block;
    max-width: 100%;
    height: auto;
    margin: 22px auto;
    border-radius: 12px;
    box-shadow: var(--xb-shadow);
    cursor: zoom-in;
}

.xb-content video {
    display: block;
    width: 100%;
    margin: 22px auto;
    border-radius: 12px;
    background: #000;
}
.xb-content audio {
    display: block;
    width: 100%;
    margin: 22px auto;
}

.xb-content iframe {
    display: block;
    width: 100%;
    aspect-ratio: 16 / 9;
    margin: 22px auto;
    border: 0;
    border-radius: 12px;
}

.xb-content blockquote {
    margin: 22px 0;
    padding: 14px 20px;
    border-left: 4px solid var(--xb-accent);
    background: var(--xb-accent-soft);
    border-radius: 0 10px 10px 0;
    color: var(--xb-text-2);
}
.xb-content blockquote p:last-child { margin-bottom: 0; }

.xb-content ul, .xb-content ol { margin: 0 0 18px; padding-left: 26px; }
.xb-content li { margin-bottom: 8px; }

.xb-content code {
    background: var(--xb-accent-soft);
    color: var(--xb-accent-deep);
    padding: 2px 7px;
    border-radius: 6px;
    font-size: 0.9em;
}
.xb-content pre {
    margin: 22px 0;
    padding: 18px 20px;
    background: var(--xb-accent-soft);
    border-radius: 12px;
    overflow-x: auto;
    font-size: 14px;
    line-height: 1.7;
}
.xb-content pre code { background: none; padding: 0; }

.xb-content table {
    width: 100%;
    margin: 22px 0;
    border-collapse: collapse;
    font-size: 14.5px;
}
.xb-content th, .xb-content td {
    border: 1px solid var(--xb-border);
    padding: 10px 14px;
    text-align: left;
}
.xb-content th { background: var(--xb-accent-soft); font-weight: 600; }

.xb-content a { color: var(--xb-accent-deep); border-bottom: 1px dashed var(--xb-accent); }
.xb-content hr { border: none; border-top: 1px dashed var(--xb-border); margin: 30px 0; }

/* ---------- 上一篇/下一篇 ---------- */
.xb-adjacent {
    margin-top: 26px;
    display: flex;
    gap: 16px;
}
.xb-adj-item {
    flex: 1;
    min-height: 74px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    padding: 16px 20px;
    background: var(--xb-card);
    border: 1px solid var(--xb-border);
    border-radius: 14px;
    transition: all 0.2s ease;
}
.xb-adj-item:hover { border-color: var(--xb-accent); transform: translateY(-2px); }
.xb-adj-right { text-align: right; }
.xb-adj-empty { visibility: hidden; }
.xb-adj-label { font-size: 12.5px; color: var(--xb-text-2); }
.xb-adj-title { font-size: 14.5px; font-weight: 600; color: var(--xb-text); }

.xb-back { margin-top: 22px; text-align: center; }
.xb-back-btn {
    display: inline-block;
    padding: 10px 26px;
    border-radius: 999px;
    background: var(--xb-accent);
    color: #fff;
    font-size: 14.5px;
    transition: all 0.2s ease;
}
.xb-back-btn:hover { background: var(--xb-accent-deep); }

/* ---------- 页脚 ---------- */
.xb-footer {
    margin-top: 48px;
    text-align: center;
    font-size: 13px;
    color: var(--xb-text-2);
    letter-spacing: 1px;
}

/* ---------- 灯箱 ---------- */
.xb-lightbox {
    position: fixed;
    inset: 0;
    z-index: 999;
    background: rgba(10, 10, 12, 0.88);
    display: none;
    align-items: center;
    justify-content: center;
    cursor: zoom-out;
}
.xb-lightbox.active { display: flex; }
.xb-lightbox img {
    max-width: 92vw;
    max-height: 92vh;
    border-radius: 10px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

/* ---------- 响应式：820 ---------- */
@media (max-width: 820px) {
    .xb-wrap { padding: 40px 16px 32px; }
    .xb-hero-name { font-size: 32px; }
    .xb-post { padding: 28px 24px; }
    .xb-post-title { font-size: 25px; }
}

/* ---------- 响应式：640 ---------- */
@media (max-width: 640px) {
    .xb-theme-toggle { top: 14px; right: 14px; width: 42px; height: 42px; }
    .xb-hero { padding: 24px 0 36px; }
    .xb-hero-emoji { font-size: 42px; }
    .xb-hero-name { font-size: 27px; }
    .xb-card-body { padding: 18px 18px 16px; }
    .xb-card-title { font-size: 18px; }
    .xb-post { padding: 22px 18px; border-radius: 16px; }
    .xb-post-title { font-size: 22px; }
    .xb-content { font-size: 15.5px; }
    .xb-adjacent { flex-direction: column; }
    .xb-adj-right { text-align: left; }
}

/* ---------- 响应式：480 ---------- */
@media (max-width: 480px) {
    .xb-hero-name { font-size: 24px; letter-spacing: 1px; }
    .xb-card-cover { aspect-ratio: 16 / 9; }
    .xb-page { gap: 10px; }
    .xb-page-btn { padding: 8px 14px; font-size: 13px; }
}

/* ---------- 无障碍：减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
    .xb-card, .xb-card-cover img, .xb-theme-toggle, .xb-adj-item { transition: none; }
}