/*!
* Clean Blog - 暗黑版 (融合 GitHub Dark Markdown 风格)
* MIT 开源协议
*/

/* ========== 全局底层规范 ========== */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
    background-color: #0d1117; /* 暗黑背景 */
    color: #c9d1d9; /* 暗黑文本色 */
    line-height: 1.6;
}

p { line-height: 1.8; margin-bottom: 1.5rem; }

a { color: #58a6ff; text-decoration: none; }
a:hover { color: #79c0ff; text-decoration: underline; }

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    color: #c9d1d9;
    margin-top: 24px;
    margin-bottom: 16px;
}

/* ========== 导航栏 ========== */
#mainNav {
    background-color: rgba(13, 17, 23, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid #30363d;
    padding-top: 1rem;
    padding-bottom: 1rem;
}

#mainNav .navbar-brand {
    color: #c9d1d9;
    font-weight: 700;
    font-size: 1.25rem;
}

#mainNav .navbar-toggler {
    font-size: 0.75rem;
    font-weight: 700;
    padding: 0.6rem 1rem;
    color: #c9d1d9;
    border: 1px solid #30363d;
    border-radius: 4px;
}

#mainNav .navbar-nav .nav-item .nav-link {
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 0.0625em;
    color: #8b949e;
}

#mainNav .navbar-nav .nav-item .nav-link:hover,
#mainNav .navbar-nav .nav-item .nav-link:focus {
    color: #58a6ff;
}

/* ========== 头部 Banner (缩小标题) ========== */
.masthead {
    padding-top: calc(4rem + 57px);
    padding-bottom: 4rem;
    background: #161b22 no-repeat center center;
    background-size: cover;
    position: relative;
    border-bottom: 1px solid #30363d;
}

.masthead::before {
    content: "";
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0, 0, 0, 0.6); /* 增强背景图上的文字对比度 */
}

.masthead .page-heading,
.masthead .post-heading,
.masthead .site-heading {
    color: #fff;
    position: relative;
    text-align: center;
}

/* 缩小主页标题 */
.masthead .site-heading h1, 
.masthead .page-heading h1 {
    font-size: 2.2rem; /* 从 4rem 缩小 */
    margin-bottom: 0.5rem;
}
.masthead .site-heading .subheading,
.masthead .page-heading .subheading {
    font-size: 1rem; /* 从 1.5rem 缩小 */
    font-weight: 300;
    color: #8b949e;
}

/* 缩小文章页标题 */
.masthead .post-heading h1 {
    font-size: 1.8rem; /* 从 2.5rem 缩小 */
    margin-bottom: 0.5rem;
}
.masthead .post-heading .subheading {
    font-size: 1rem; /* 从 1.25rem 缩小 */
    font-weight: 300;
    margin: 0.625rem 0 1rem;
    display: block;
    color: #8b949e;
}
.masthead .post-heading .meta {
    font-style: italic;
    font-weight: 300;
    font-size: 0.9rem;
    color: #8b949e;
}

/* ========== 首页文章列表 (缩小字体) ========== */
.post-preview > a {
    color: #c9d1d9;
    text-decoration: none;
}
.post-preview > a:hover,
.post-preview > a:focus {
    color: #58a6ff;
}
.post-preview > a > .post-title {
    font-size: 1.25rem; /* 从 1.75rem 缩小 */
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
}
.post-preview > a > .post-subtitle {
    font-weight: 300;
    font-size: 0.95rem; /* 缩小副标题 */
    margin: 0 0 0.5rem;
    color: #8b949e;
}
.post-preview .post-meta {
    color: #8b949e;
    font-size: 0.8rem;
    font-style: italic;
}
hr.my-4 {
    border-color: #30363d;
    opacity: 1;
}

/* ========== 文章正文 (继承 1.html 的 Markdown 样式) ========== */
.markdown-body {
    width: 100%;
    background-color: #0d1117;
    color: #c9d1d9;
    padding: 20px 0;
}
.markdown-body h2 {
    font-size: 1.5em;
    border-bottom: 1px solid #30363d;
    padding-bottom: .3em;
    margin-top: 1.5em;
}
.markdown-body h3 {
    font-size: 1.25em;
}
.markdown-body ul, .markdown-body ol {
    padding-left: 2em;
    margin-bottom: 16px;
}
.markdown-body li { margin-bottom: 0.25em; }

/* 本地图片的响应式物理防溢出重绘 */
.markdown-body img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
    margin: 2rem auto;
    border-radius: 6px;
    border: 1px solid #30363d;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

/* 提示框定制 */
.markdown-body blockquote {
    border-left: 5px solid #d73a49;
    background-color: rgba(215, 58, 73, 0.15);
    padding: 1em 1.5em;
    margin: 0 0 16px 0;
    color: #c9d1d9;
    font-weight: 500;
}

/* ========== 按钮 ========== */
.btn-primary {
    background-color: #238636;
    border-color: #238636;
    border-radius: 6px;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 600;
}
.btn-primary:hover {
    background-color: #2ea043;
    border-color: #2ea043;
}

/* ========== 页脚 ========== */
footer {
    padding: 2rem 0;
    color: #8b949e;
    border-top: 1px solid #30363d !important;
    background-color: #0d1117;
}
footer .fa-stack { color: #8b949e; transition: color 0.2s ease; }
footer .fa-stack:hover { color: #c9d1d9; }
footer .small { color: #8b949e !important; }