:root {
    --primary-color: #d2232a;
    --dark-color: #222;
    --light-color: #fefefe;
    --gray-light: #f8f9fa;
    --gray-border: #eee;
    --text-primary: #333;
    --text-secondary: #666;
    --text-light: #888;
    --card-shadow: 0 4px 12px rgba(0,0,0,0.05);
    --card-hover-shadow: 0 8px 24px rgba(210,35,42,0.1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }

body {
    font-family: 'Noto Sans SC', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--light-color);
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    overflow-x: hidden;
    -webkit-text-size-adjust: 100%;
    background-image: 
        radial-gradient(circle at 10% 20%, rgba(210,35,42,0.03) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, rgba(34,34,34,0.03) 0%, transparent 20%);
}

@media (max-width: 768px) { html { font-size: 15px; } }
@media (max-width: 480px) { 
    html { font-size: 14px; } 
    body { padding: 15px; background-image: none; }
}

/* 头部通用 */
header {
    text-align: center;
    padding: 3rem 1rem 2rem;
    border-bottom: 1px solid var(--gray-border);
    margin-bottom: 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: var(--card-shadow);
    margin-top: 1rem;
}
@media (max-width: 768px) { header { padding: 2rem 1rem 1.5rem; margin-bottom: 1.5rem; } }

h1, .site-title, .blog-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 300;
    letter-spacing: -0.02em;
    margin-bottom: 0.75rem;
    color: var(--dark-color);
    line-height: 1.2;
}

.subtitle, .site-subtitle, .blog-subtitle {
    font-size: 1.1rem;
    font-weight: 400;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 1.5rem;
    line-height: 1.5;
}

/* 导航标签 - 通用 */
.nav-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 1rem;
}
.nav-tabs {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.5rem;
    padding-bottom: 0.5rem;
    -webkit-overflow-scrolling: touch;
}
.nav-tab {
    color: var(--text-primary);
    text-decoration: none;
    padding: 0.6rem 1.2rem;
    border-radius: 20px;
    transition: all 0.3s ease;
    font-weight: 500;
    font-size: 0.95rem;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    touch-action: manipulation;
    background: var(--gray-light);
    border: 1px solid var(--gray-border);
    white-space: nowrap;
    flex-shrink: 0;
}
.nav-tab:hover {
    color: var(--primary-color);
    background: rgba(210,35,42,0.05);
    border-color: rgba(210,35,42,0.2);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(210,35,42,0.1);
}
.nav-tab.active {
    color: var(--primary-color);
    background: rgba(210,35,42,0.1);
    border-color: rgba(210,35,42,0.3);
}

/* 窄屏导航优化 - 强制一行显示，等宽，溢出省略 */
@media (max-width: 600px) {
    .nav-tabs {
        flex-wrap: nowrap;           /* 强制不换行 */
        gap: 0.1rem;                 /* 间隙最小化 */
        justify-content: space-between;
    }
    .nav-tab {
        padding: 0.3rem 0.1rem;      /* 内边距极致压缩 */
        font-size: 0.7rem;            /* 字体缩小到约11px */
        min-width: 0;                 /* 允许收缩 */
        flex: 1 1 0;                  /* 等宽分配 */
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;      /* 长文字显示省略号 */
    }
}

/* 章节 */
section {
    padding: 3rem 1rem;
    border-bottom: 1px solid var(--gray-border);
}
section:last-of-type { border-bottom: none; }
@media (max-width: 768px) { section { padding: 2.5rem 1rem; } }

.section-title {
    font-size: 1.8rem;
    font-weight: 500;
    text-align: center;
    margin-bottom: 2.5rem;
    color: var(--dark-color);
    position: relative;
}
@media (max-width: 768px) { .section-title { font-size: 1.6rem; margin-bottom: 2rem; } }
.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 2px;
    background: var(--primary-color);
    margin: 0.75rem auto;
}

/* 粒子区域 (index) */
#particle-section {
    min-height: 60vh;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: center;
    overflow: hidden;
}
#particle-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: block;
    background: transparent;
    pointer-events: none;
}
.particle-controls {
    position: relative;
    z-index: 2;
    text-align: center;
    margin-top: 2rem;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.75rem;
}
.control-btn {
    background: var(--dark-color);
    color: white;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 30px;
    cursor: pointer;
    font-family: inherit;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.3s ease;
    min-height: 44px;
    min-width: 120px;
    touch-action: manipulation;
    border: 2px solid var(--dark-color);
}
@media (max-width: 480px) {
    .control-btn { min-width: 110px; padding: 0.7rem 1.2rem; font-size: 0.9rem; }
}
.control-btn:hover {
    background: var(--primary-color);
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(210,35,42,0.2);
}
.control-btn:active { transform: translateY(0); }

/* 时间线 (index) */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}
.timeline::before {
    content: '';
    position: absolute;
    left: 30px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: #ddd;
}
@media (min-width: 769px) {
    .timeline::before { left: 50%; transform: translateX(-50%); }
}
.timeline-item {
    position: relative;
    margin-bottom: 2.5rem;
    width: 100%;
}
.timeline-content {
    position: relative;
    width: calc(100% - 70px);
    margin-left: 70px;
    padding: 1.5rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.05);
    border-left: 3px solid var(--primary-color);
}
@media (min-width: 769px) {
    .timeline-content {
        width: calc(50% - 40px);
        margin-left: 0;
    }
    .timeline-item:nth-child(odd) .timeline-content {
        margin-left: auto;
        border-left: none;
        border-right: 3px solid var(--dark-color);
    }
}
.timeline-content h3 { font-size: 1.2rem; margin-bottom: 0.5rem; color: var(--dark-color); }
.timeline-content p { color: var(--text-secondary); font-size: 0.95rem; line-height: 1.5; }

/* 平衡器 (index) */
.balance-container {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}
.balance-visual {
    height: 180px;
    position: relative;
    margin: 2.5rem 0;
}
@media (max-width: 768px) { .balance-visual { height: 160px; margin: 2rem 0; } }
.balance-beam {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 85%;
    height: 4px;
    background: var(--dark-color);
    transform: translate(-50%, -50%) rotate(var(--beam-angle,0deg));
    transform-origin: center;
    transition: transform 0.8s cubic-bezier(0.34,1.56,0.64,1);
}
.weight {
    position: absolute;
    top: 50%;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    border-radius: 50%;
    transform: translate(-50%,-50%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    font-size: 1.1rem;
    box-shadow: 0 4px 12px rgba(210,35,42,0.25);
}
@media (max-width: 480px) { .weight { width: 45px; height: 45px; font-size: 1rem; } }
.weight-knowledge { left: 30%; }
.weight-action { left: 70%; }
.slider-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    margin-top: 2rem;
}
@media (min-width: 481px) {
    .slider-container {
        flex-direction: row;
        justify-content: center;
        gap: 2rem;
    }
}
.slider-wrapper {
    width: 100%;
    max-width: 280px;
}
.slider-wrapper label {
    display: block;
    margin-bottom: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    font-size: 0.95rem;
}
input[type=range] {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    background: #e0e0e0;
    border-radius: 3px;
    outline: none;
}
input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 22px;
    height: 22px;
    background: var(--dark-color);
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid white;
    box-shadow: 0 2px 6px rgba(0,0,0,0.2);
}
input[type=range]::-webkit-slider-thumb:active { background: var(--primary-color); }

/* 关于我 (blog) */
.about-me {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 2rem;
}
.avatar {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: linear-gradient(135deg,#f5f5f5,#e0e0e0);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--primary-color);
    margin: 0 auto 1.5rem;
    border: 3px solid white;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    font-weight: bold;
}
.intro-text {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
}
.current-focus {
    display: inline-flex;
    align-items: center;
    background: rgba(210,35,42,0.1);
    color: var(--primary-color);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    margin-top: 1rem;
}

/* 文章卡片网格 (blog) */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    max-width: 1000px;
    margin: 0 auto;
}
@media (max-width: 768px) { .articles-grid { grid-template-columns: 1fr; } }
.article-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--gray-border);
    height: 100%;
    display: flex;
    flex-direction: column;
}
.article-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--card-hover-shadow);
    border-color: rgba(210,35,42,0.2);
}
.article-header {
    padding: 1.2rem;
    border-bottom: 1px solid var(--gray-border);
    background: linear-gradient(135deg, var(--gray-light), #f0f0f0);
}
.article-category {
    display: inline-block;
    background: rgba(210,35,42,0.1);
    color: var(--primary-color);
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: 0.6rem;
}
.article-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.3rem;
    color: var(--dark-color);
    line-height: 1.4;
}
.article-date {
    font-size: 0.8rem;
    color: var(--text-light);
}
.article-content {
    padding: 1.2rem;
    color: var(--text-secondary);
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}
.article-content p {
    margin-bottom: 0.8rem;
    line-height: 1.6;
    flex-grow: 1;
    font-size: 0.95rem;
}
.read-more {
    display: inline-flex;
    align-items: center;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    margin-top: 0.8rem;
    font-size: 0.9rem;
    padding: 0.3rem 0;
    border-bottom: 1px solid transparent;
    transition: all 0.3s ease;
    align-self: flex-start;
}
.read-more:hover {
    border-bottom-color: var(--primary-color);
    padding-left: 5px;
}

/* 项目展示 (works) */
.projects-showcase {
    max-width: 800px;
    margin: 0 auto;
}
.project-item {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin-bottom: 2.5rem;
    padding: 1.5rem;
    background: white;
    border-radius: 10px;
    border: 1px solid var(--gray-border);
    box-shadow: var(--card-shadow);
}
@media (min-width: 769px) {
    .project-item {
        flex-direction: row;
        align-items: center;
    }
    .project-item:nth-child(even) { flex-direction: row-reverse; }
}
.project-icon {
    flex: 0 0 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--gray-light), #e9ecef);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: var(--primary-color);
    box-shadow: 0 3px 10px rgba(0,0,0,0.05);
}
.project-details { flex: 1; }
.project-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--dark-color);
}
.project-desc {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 0.95rem;
}

/* 联系 */
.contact-section {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}
.email-wrapper { display: inline-block; margin: 1.5rem 0; }
.email-link {
    display: inline-block;
    font-size: 1.1rem;
    color: var(--primary-color);
    text-decoration: none;
    padding: 0.7rem 1.3rem;
    border: 2px solid var(--primary-color);
    border-radius: 25px;
    transition: all 0.3s ease;
    background: rgba(210,35,42,0.05);
}
.email-link:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(210,35,42,0.2);
}
.support-note {
    margin-top: 2rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(210,35,42,0.03), rgba(34,34,34,0.03));
    border-radius: 10px;
    border: 1px solid var(--gray-border);
}
.support-note h3 {
    color: var(--dark-color);
    margin-bottom: 0.8rem;
    font-size: 1.1rem;
}
.support-note p {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 0.95rem;
}

/* 工具卡片 (works) */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    max-width: 1200px;
    margin: 0 auto;
}
@media (max-width: 768px) { .tools-grid { grid-template-columns: 1fr; } }
.tool-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--gray-border);
    display: flex;
    flex-direction: column;
    height: 100%;
}
.tool-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--card-hover-shadow);
    border-color: rgba(210,35,42,0.2);
}
.tool-header {
    padding: 1.2rem;
    border-bottom: 1px solid var(--gray-border);
    background: linear-gradient(135deg, var(--gray-light), #f0f0f0);
}
.tool-icon {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: white;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 0.8rem;
    font-size: 1.4rem;
    color: var(--primary-color);
    box-shadow: 0 3px 8px rgba(0,0,0,0.08);
    border: 2px solid rgba(210,35,42,0.1);
}
@media (max-width: 480px) {
    .tool-icon { width: 45px; height: 45px; font-size: 1.2rem; margin-bottom: 0.6rem; }
}
.tool-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.3rem;
    color: var(--dark-color);
    line-height: 1.3;
}
.tool-count {
    display: inline-block;
    background: rgba(210,35,42,0.1);
    color: var(--primary-color);
    padding: 0.2rem 0.6rem;
    border-radius: 15px;
    font-size: 0.75rem;
    font-weight: 500;
}
.tool-content {
    padding: 1.2rem;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}
.tool-desc {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
    font-size: 0.9rem;
    flex-grow: 1;
}
.tool-links {
    list-style: none;
    margin: 0;
    padding: 0;
}
.tool-link-item {
    margin-bottom: 0.6rem;
    position: relative;
    padding-left: 1rem;
}
.tool-link-item:last-child { margin-bottom: 0; }
.tool-link-item::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
    transition: transform 0.2s ease;
    font-size: 0.85rem;
}
.tool-link-item:hover::before { transform: translateX(3px); }
.tool-link-item a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    display: block;
    padding: 0.3rem 0;
    border-bottom: 1px solid transparent;
    transition: all 0.3s ease;
    font-size: 0.9rem;
    line-height: 1.4;
}
.tool-link-item a:hover {
    color: var(--primary-color);
    border-bottom-color: rgba(210,35,42,0.3);
    padding-left: 5px;
}
.usage-tag {
    display: inline-block;
    font-size: 0.7rem;
    padding: 0.2rem 0.5rem;
    border-radius: 10px;
    margin-left: 0.5rem;
    vertical-align: middle;
}
.tag-using { background: rgba(42,123,210,0.1); color: #2a7bd2; }
.tag-new { background: rgba(210,35,42,0.1); color: var(--primary-color); }
.tag-trying { background: rgba(155,155,155,0.1); color: var(--text-light); }
.tool-footer {
    padding: 1rem;
    background: var(--gray-light);
    border-top: 1px solid var(--gray-border);
    text-align: center;
}
.explore-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--dark-color);
    color: white;
    text-decoration: none;
    padding: 0.5rem 1.2rem;
    border-radius: 20px;
    font-weight: 500;
    transition: all 0.3s ease;
    width: 100%;
    max-width: 160px;
    min-height: 40px;
    font-size: 0.9rem;
    touch-action: manipulation;
    border: 2px solid var(--dark-color);
}
.explore-btn:hover {
    background: var(--primary-color);
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(210,35,42,0.2);
}

/* 快速查找 (works) */
.quick-find {
    max-width: 900px;
    margin: 3rem auto 2rem;
    padding: 1.5rem;
    background: white;
    border-radius: 12px;
    border: 1px solid var(--gray-border);
    box-shadow: var(--card-shadow);
}
@media (max-width: 768px) { .quick-find { padding: 1.2rem; margin: 2.5rem auto 1.5rem; } }
.quick-find h3 { text-align: center; font-size: 1.2rem; margin-bottom: 1.2rem; color: var(--dark-color); }
.find-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.6rem;
}
@media (max-width: 480px) { .find-tags { gap: 0.5rem; } }
.find-tag {
    background: var(--gray-light);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    border: 1px solid var(--gray-border);
    transition: all 0.3s ease;
    font-size: 0.85rem;
    min-height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    touch-action: manipulation;
}
.find-tag:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 3px 6px rgba(210,35,42,0.15);
}

/* 个人推荐 (works) */
.personal-recommend {
    max-width: 800px;
    margin: 2rem auto;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(210,35,42,0.03), rgba(34,34,34,0.03));
    border-radius: 10px;
    border: 1px solid var(--gray-border);
    text-align: center;
}
.recommend-title { font-size: 1.1rem; color: var(--dark-color); margin-bottom: 0.8rem; }
.recommend-text { color: var(--text-secondary); line-height: 1.6; font-size: 0.95rem; margin-bottom: 1rem; }

/* 底部导航 (通用) */
.footer-links {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 1.5rem;
    margin: 3rem 0 2rem;
    padding: 1.5rem;
    background: var(--gray-light);
    border-radius: 12px;
    border: 1px solid var(--gray-border);
}
.footer-link {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 44px;
    min-width: 100px;
    text-align: center;
    touch-action: manipulation;
    background: white;
    border: 1px solid var(--gray-border);
}
.footer-link:hover {
    color: var(--primary-color);
    background: rgba(210,35,42,0.05);
    transform: translateY(-2px);
    border-color: rgba(210,35,42,0.3);
    box-shadow: 0 4px 8px rgba(210,35,42,0.1);
}
.footer-link:active { transform: translateY(0); }
.link-divider {
    color: #ccc;
    font-weight: 300;
    font-size: 1.2rem;
}

/* 窄屏底部导航优化 - 强制一行显示，等宽，溢出省略 */
@media (max-width: 600px) {
    .footer-links {
        flex-wrap: nowrap;           /* 强制不换行 */
        gap: 0.1rem;                 /* 间隙最小化 */
        padding: 0.8rem 0.3rem;      /* 减少内边距 */
    }
    .footer-link {
        padding: 0.3rem 0.1rem;      /* 按钮内边距极致压缩 */
        font-size: 0.7rem;            /* 字体缩小到约11px */
        min-width: 0;                 /* 允许收缩 */
        flex: 1 1 0;                  /* 等宽分配 */
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;      /* 长文字显示省略号 */
    }
    .link-divider {
        display: none;                 /* 隐藏分隔符，腾出空间 */
    }
}

footer {
    text-align: center;
    padding: 2.5rem 1rem;
    color: var(--text-light);
    font-size: 0.9rem;
    background: white;
    border-radius: 12px;
    border: 1px solid var(--gray-border);
}
footer p { margin-bottom: 0.5rem; line-height: 1.5; }
.copyright { font-size: 0.85rem; opacity: 0.8; margin-top: 0.5rem; }

/* 文章页专用样式 (post layout) */
.post-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 1rem;
    background: white;
    border-radius: 12px;
    box-shadow: var(--card-shadow);
    border: 1px solid var(--gray-border);
}
.post-content h1 {
    font-size: 2rem;
    font-weight: 400;
    color: var(--dark-color);
    margin-bottom: 1rem;
}
.post-meta {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--gray-border);
}
.post-category {
    display: inline-block;
    background: rgba(210,35,42,0.1);
    color: var(--primary-color);
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 500;
    margin-right: 1rem;
}
.post-content p {
    margin-bottom: 1.2rem;
    line-height: 1.8;
    color: var(--text-secondary);
}
.post-content h2, .post-content h3 {
    margin: 2rem 0 1rem;
    color: var(--dark-color);
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: var(--primary-color, #d2232a);
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
    z-index: 1000;
    border: none;
    outline: none;
}
.back-to-top.show {
    opacity: 0.8;
    visibility: visible;
}
.back-to-top:hover {
    opacity: 1;
    transform: translateY(-3px);
}
@media (max-width: 480px) {
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
        font-size: 20px;
    }
}