/* ── 顶栏 ─────────────────────────────────────── */

.topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 3rem;
    padding: 0 1rem 0 0.5rem;
    background: var(--topbar-bg);
    border-bottom: 1px solid var(--topbar-border);
    z-index: 100;
}

.topbar-left {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

#home-link,
#toc-toggle,
#theme-toggle {
    flex-shrink: 0;
    background: transparent;
    border: none;
    padding: 0;
    width: 1.7rem;
    height: 1.7rem;
    cursor: pointer;
    color: var(--toggle-color);
    transition: color 0.2s ease;
    border-radius: 50%;
    outline: none;
    -webkit-tap-highlight-color: transparent;
    -webkit-appearance: none;
    appearance: none;
    display: flex;
    align-items: center;
    justify-content: center;
}

#home-link svg,
#toc-toggle svg,
#theme-toggle svg {
    fill: currentColor;
    width: 1.7rem;
    height: 1.7rem;
}

#home-link:hover,
#toc-toggle:hover,
#theme-toggle:hover {
    outline: none;
    background: transparent;
    color: var(--icon-link-hover);
}

/* ── 页面布局 ──────────────────────────────── */

.page-body {
    display: flex;
    margin-top: 1rem;
    overflow-x: hidden;
}

.toc-sidebar {
    position: fixed;
    top: 2.5rem;
    left: 0;
    bottom: 0;
    width: 280px;
    background: var(--toc-bg);
    border-right: 1px solid var(--toc-border);
    transform: translateX(-280px);
    transition: transform 0.3s ease;
    overflow-y: auto;
    z-index: 99;
    padding: 0.75rem 0;
}

.toc-sidebar ul,
.toc-sidebar ol {
    padding-left: 2rem;
    margin: 0;
    list-style: none;
}

body.toc-open .toc-sidebar {
    transform: translateX(0);
}

.post-wrapper {
    flex: 1;
    min-width: 0;
    overflow-x: hidden;
    transition: margin-left 0.3s ease;
}

body.toc-open .post-wrapper {
    margin-left: 280px;
}

.post-body {
    padding: 2rem 2rem 4rem;
    overflow-wrap: break-word;
    word-break: break-word;
}

/* ── 遮罩层 ─────────────────────────────────── */

.toc-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--toc-overlay-bg, rgba(0, 0, 0, 0.5));
    z-index: 98;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
    /* 桌面端默认不显示 */
    display: none;
}

@media (max-width: 600px) {
    .toc-overlay {
        display: block;
    }

    body.toc-open .toc-overlay {
        opacity: 1;
        visibility: visible;
    }

    .toc-sidebar {
        z-index: 99;
    }

    body.toc-open .post-wrapper {
        margin-left: 0 !important;
    }

    .post-body {
        padding: 1.5rem 1rem 3rem;
    }
}

@media (min-width: 601px) {
    .post-wrapper {
        transition: margin-left 0.3s ease;
    }

    .post-body {
        max-width: 1200px;
        margin: 0 auto;
    }
}

@media (min-width: 1201px) {
    .toc-sidebar {
        width: 320px;
        transform: translateX(-320px);
    }

    body.toc-open .post-wrapper {
        margin-left: 320px;
    }
}

/* ── 目录项 ────────────────────────────────── */

.toc-title {
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--toc-heading-color);
    padding: 0.5rem 2rem 0.5rem;
    border-bottom: 1px solid var(--toc-border);
    margin-bottom: 0.5rem;
}

.toc-item {
    display: block;
    padding: 0.4rem 0.5rem 0.4rem 0.5rem;
    color: var(--toc-link-color);
    text-decoration: none;
    font-size: 0.9rem;
    line-height: 1.2;
    transition: color 0.15s, background 0.15s;
}

.toc-item:hover {
    color: var(--toc-active-color);
    background: var(--toc-hover-bg);
}

.toc-item.toc-active {
    color: var(--toc-active-color);
    font-weight: 600;
}

/* ── 文章通用样式（与主题无关） ─────────────────── */

html {
    font-size: 14px;
}

@media (min-width: 601px) {
    html {
        font-size: 18px;
    }
}

body {
    margin: 0;
    font-family: "Open Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--page-bg);
    color: var(--page-text);
    line-height: 1.6;
}

/* ── 代码块容器 ─────────────────────────────── */

.post-code-block {
    background: var(--post-code-bg);
    border: 2px solid var(--post-code-border);
    border-radius: 0.25rem;
    margin: 1em 0;
}

/* ── 语言标签 ───────────────────────────────── */

.post-code-lang {
    display: block;
    padding: 0.25rem 0.75rem;
    font-size: 0.8rem;
    color: var(--post-code-lang-color);
    background: var(--post-code-lang-bg);
    border-bottom: 1px solid var(--post-code-border);
    text-transform: uppercase;
    letter-spacing: 0.03125rem;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
}

/* ── 双列布局：行号 + 代码 ─────────────────── */

.post-code-content {
    display: grid;
    overflow-x: auto;
}

.post-code-line-numbers {
    box-sizing: border-box;
    overflow: hidden;
    text-align: right;
    padding: 0.25rem 0.5rem 0.25rem 0.5rem;
    border-right: 1px solid var(--post-code-line-border);
    color: var(--post-code-line-color);
    user-select: none;
    line-height: 1.6;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
    font-size: 1rem;
    margin: 0;
}

.post-code-content pre {
    margin: 0;
    padding: 0.25rem 0.5rem 0.25rem 0.5rem;
    min-width: 0;
    overflow-x: auto;
}

.post-code-content pre code.hljs {
    background: transparent;
    padding: 0;
    display: inline;
    overflow-x: visible;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
    font-size: 0.9rem;
    line-height: 1.6;
}

/* ── 数学公式 ────────────────────────────────── */

/* ── 行内代码 ─────────────────────────────── */

.post-body code:not(.hljs) {
    background-color: var(--inline-code-bg);
    border: 1px solid var(--inline-code-border);
    border-radius: 0.1875rem;
    padding: 0 0.125rem 0 0.125rem;
    font-size: 0.9rem;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
    overflow-wrap: break-word;
    word-break: break-word;
}

mjx-container[display="true"] {
    overflow-x: auto;
    overflow-y: hidden;
}

/* ── 图片自适应 ──────────────────────────────── */

img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
}

/* ── 引用块 ──────────────────────────────────── */

.post-body blockquote {
    margin: 0.8em 0;
    padding: 0 0.9375rem;
    border-left: 0.25rem solid var(--quote-border-color);
    color: var(--quote-color);
}

.post-body blockquote blockquote {
    margin: 0.5em 0;
    padding-right: 0;
}

/* ── 提示容器（GitHub Alerts） ──────────────────── */

.markdown-alert {
    padding: 0 1em;
    margin: 1rem 1rem;
    color: inherit;
    border-left: 0.25rem solid var(--alert-border);
}

.markdown-alert-title {
    font-weight: 700;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.15rem;
    color: var(--alert-border);
}

.markdown-alert-title svg {
    fill: currentColor;
    flex-shrink: 0;
    position: relative;
    top: 0.125em;
    margin-right: 1ch;
    overflow: visible;
}

.markdown-alert-note       { --alert-border: var(--alert-note-border); }
.markdown-alert-tip        { --alert-border: var(--alert-tip-border); }
.markdown-alert-important  { --alert-border: var(--alert-important-border); }
.markdown-alert-warning    { --alert-border: var(--alert-warning-border); }
.markdown-alert-caution    { --alert-border: var(--alert-caution-border); }

.markdown-alert .markdown-alert {
    margin: 0.5em 0;
}

/* ── Mermaid 图表 ─────────────────────────────── */

.mermaid {
    text-align: center;
    overflow-x: auto;
    margin: 1em 0;
}

/* ── 超链接 ─────────────────────────────────── */

.post-body a {
    color: var(--link-color);
    text-decoration: none;
}

.post-body a:hover {
    text-decoration: underline;
}

/* ── 表格 ──────────────────────────────────── */

.post-body table {
    padding: 0;
    word-break: initial;
    border-collapse: collapse;
    margin: 0.8em 0;
    width: 100%;
}

.post-body table tr {
    border: 2px solid var(--table-border-color);
    margin: 0;
    padding: 0;
}

.post-body table tr:nth-child(2n),
.post-body thead {
    background-color: var(--table-header-bg);
}

.post-body table th {
    font-weight: bold;
    border: 2px solid var(--table-border-color);
    border-bottom-width: 0.125rem;
    margin: 0;
    padding: 0.375rem 0.8125rem;
}

.post-body table td {
    border: 2px solid var(--table-border-color);
    margin: 0;
    padding: 0.375rem 0.8125rem;
}

.post-body table th:first-child,
.post-body table td:first-child {
    margin-top: 0;
}

.post-body table th:last-child,
.post-body table td:last-child {
    margin-bottom: 0;
}

/* ── 列表 ──────────────────────────────────── */

.post-body ul,
.post-body ol {
    padding-left: 1.6rem;
    margin: 0.8rem 0;
}

.post-body li {
    margin: 0.4rem 0;
}

.post-body li > p {
    margin: 0;
}

.post-body li > ol,
.post-body li > ul {
    margin: 0 0;
}

/* ── 任务列表 ──────────────────────────────── */

.post-body .task-list-item {
    list-style: none;
}

.post-body .task-list-item-checkbox {
    margin-left: -1.3rem;
    width: 1rem;
    height: 1rem;
    accent-color: var(--task-checkbox-accent);
    vertical-align: middle;
    pointer-events: none;
    cursor: default;
}

/* ── 标题 ──────────────────────────────────── */

.post-body h1,
.post-body h2,
.post-body h3,
.post-body h4,
.post-body h5,
.post-body h6 {
    position: relative;
    margin-top: 1rem;
    margin-bottom: 1rem;
    font-weight: bold;
    line-height: 1.4;
    cursor: text;
}

.post-body h1 {
    font-size: 2.25rem;
    line-height: 1.2;
}

.post-body h2 {
    font-size: 2rem;
    line-height: 1.225;
}

.post-body h3 {
    font-size: 1.75rem;
    line-height: 1.43;
}

.post-body h4 {
    font-size: 1.5rem;
}

.post-body h5 {
    font-size: 1.25rem;
}

.post-body h6 {
    font-size: 1.1rem;
}

/* ── 分割线 ──────────────────────────────────── */

.post-body hr {
    height: 0.125rem;
    padding: 0;
    margin: 1rem 0;
    background-color: var(--border-color);
    border: 0 none;
    overflow: hidden;
    box-sizing: content-box;
}