/* ===== 全局样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #3b82f6;
    --bg-color: #ffffff;
    --text-color: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --card-bg: #f9fafb;
    --hover-bg: #f3f4f6;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #111827;
        --text-color: #f9fafb;
        --text-secondary: #9ca3af;
        --border-color: #374151;
        --card-bg: #1f2937;
        --hover-bg: #374151;
    }
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    color: var(--primary-color);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* ===== 导航栏 ===== */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--bg-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo a {
    font-size: 1.25rem;
    font-weight: bold;
    color: var(--text-color);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 1.5rem;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-color);
    text-decoration: none;
}

/* ===== 主内容区 ===== */
main {
    flex: 1;
    max-width: 800px;
    width: 100%;
    margin: 0 auto;
    padding: 2rem;
}

section {
    margin-bottom: 3rem;
}

h1, h2, h3 {
    margin-bottom: 1rem;
    line-height: 1.3;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }

/* ===== 首页 Hero ===== */
.hero {
    text-align: center;
    padding: 3rem 0;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.hero p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* ===== 导航卡片 ===== */
.nav-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 1.5rem;
    transition: all 0.2s ease;
}

.card:hover {
    background-color: var(--hover-bg);
    transform: translateY(-2px);
}

.card a {
    color: var(--text-color);
    text-decoration: none;
    display: block;
}

.card h2 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* ===== 链接网格 ===== */
.link-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 0.75rem;
}

.link-grid a {
    display: block;
    padding: 0.75rem 1rem;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    text-align: center;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

.link-grid a:hover {
    background-color: var(--hover-bg);
    text-decoration: none;
}

/* ===== 个人主页 ===== */
.profile {
    text-align: center;
    padding: 2rem 0;
}

.avatar img {
    border-radius: 50%;
    margin-bottom: 1rem;
    border: 3px solid var(--border-color);
}

.bio {
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
}

.skills ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skills li {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.9rem;
}

.project-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.project-item {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 1rem;
}

.project-item h3 {
    margin-bottom: 0.5rem;
}

.project-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.75rem;
}

/* ===== 博客列表 ===== */
.blog-header {
    text-align: center;
    padding: 2rem 0;
}

.blog-header p {
    color: var(--text-secondary);
}

.post-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.post-item {
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    transition: background-color 0.2s ease;
}

.post-item:hover {
    background-color: var(--card-bg);
}

.post-item h2 {
    margin-bottom: 0.5rem;
}

.post-item h2 a {
    color: var(--text-color);
}

.post-item time {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.post-excerpt {
    color: var(--text-secondary);
    margin: 0.75rem 0;
    font-size: 0.95rem;
}

.post-tags {
    display: flex;
    gap: 0.5rem;
}

.tag {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 0.15rem 0.6rem;
    border-radius: 9999px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* ===== 云盘 ===== */
.drive-header {
    text-align: center;
    padding: 2rem 0;
}

.drive-header p {
    color: var(--text-secondary);
}

.file-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.file-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    transition: background-color 0.2s ease;
}

.file-item:hover {
    background-color: var(--card-bg);
}

.file-icon {
    font-size: 1.5rem;
}

.file-info {
    flex: 1;
}

.file-info h3 {
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.file-info p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.download-btn {
    padding: 0.5rem 1rem;
    background-color: var(--primary-color);
    color: white;
    border-radius: 0.375rem;
    font-size: 0.9rem;
    white-space: nowrap;
}

.download-btn:hover {
    text-decoration: none;
    opacity: 0.9;
}

.drive-notice {
    margin-top: 2rem;
    padding: 1rem;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
}

.drive-notice p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* ===== 页脚 ===== */
footer {
    text-align: center;
    padding: 1.5rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* ===== 响应式 ===== */
@media (max-width: 640px) {
    .navbar {
        padding: 1rem;
    }

    .nav-links {
        gap: 1rem;
    }

    main {
        padding: 1.5rem 1rem;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .file-item {
        flex-wrap: wrap;
    }

    .download-btn {
        width: 100%;
        text-align: center;
    }
}