/* ===== 全局重置 & 变量 ===== */
:root {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-card: #1e293b;
    --text-primary: #ffffff;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent: #38bdf8;
    --accent-hover: #7dd3fc;
    --border: #334155;
    --success: #22c55e;
    --warning: #eab308;
    --danger: #ef4444;
    --radius: 8px;
    --radius-lg: 12px;
    --max-width: 1100px;
    --nav-height: 64px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'JetBrains Mono', 'Fira Code', monospace, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: var(--accent-hover);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
}

.nav-logo {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary) !important;
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 12px;
}

.nav-links a {
    padding: 8px 14px;
    border-radius: var(--radius);
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    transition: all 0.2s;
}

.nav-links a:hover {
    color: var(--text-primary);
    background: var(--bg-secondary);
}

.nav-links a.active {
    color: var(--accent);
    background: rgba(56, 189, 248, 0.1);
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
}

/* ===== 主内容区 ===== */
.main-content {
    min-height: calc(100vh - var(--nav-height) - 60px);
    padding-top: var(--nav-height);
}

/* ===== 页脚 ===== */
.footer {
    text-align: center;
    padding: 24px 0;
    border-top: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 0.85rem;
}

/* ===== 首页 - Hero 区域 ===== */
.hero {
    min-height: calc(100vh - var(--nav-height));
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px 24px;
    text-align: center;
}

/* 终端窗口 */
.terminal {
    background: #0d1117;
    border: 1px solid #30363d;
    border-radius: var(--radius-lg);
    padding: 0;
    width: 100%;
    max-width: 600px;
    margin-bottom: 48px;
    overflow: hidden;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.terminal-header {
    background: #161b22;
    padding: 10px 16px;
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 1px solid #30363d;
}

.terminal-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.terminal-dot.red { background: #ff5f56; }
.terminal-dot.yellow { background: #ffbd2e; }
.terminal-dot.green { background: #27c93f; }

.terminal-title {
    color: var(--text-muted);
    font-size: 0.8rem;
    margin-left: 8px;
}

.terminal-body {
    padding: 24px;
    text-align: left;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
}

.terminal-line {
    margin-bottom: 12px;
    font-size: 0.95rem;
    line-height: 1.5;
}

.terminal-prompt {
    color: var(--success);
    margin-right: 8px;
}

.terminal-command {
    color: var(--text-primary);
}

.terminal-output {
    color: var(--accent);
    margin-left: 20px;
    margin-bottom: 12px;
}

.terminal-cursor {
    display: inline-block;
    width: 8px;
    height: 16px;
    background: var(--accent);
    animation: blink 1s step-end infinite;
    vertical-align: text-bottom;
}

@keyframes blink {
    50% { opacity: 0; }
}

/* Hero 标题 */
.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 12px;
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
    max-width: 500px;
}

.hero-tagline {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 32px;
}

/* Hero 按钮 */
.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
    flex-wrap: wrap;
    justify-content: center;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: var(--radius);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    font-family: inherit;
}

.btn-primary {
    background: var(--accent);
    color: #0f172a !important;
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary) !important;
    border: 1px solid var(--border);
}

.btn-outline:hover {
    border-color: var(--accent);
    color: var(--accent) !important;
    transform: translateY(-1px);
}

/* ===== 技术标签云 ===== */
.tag-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    max-width: 500px;
}

.tag {
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    transition: all 0.2s;
}

.tag:hover {
    border-color: var(--accent);
    color: var(--accent);
    transform: translateY(-1px);
}

/* ===== 页面通用标题 ===== */
.page-header {
    padding: 60px 0 40px;
    text-align: center;
}

.page-header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.page-header p {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* ===== About 页面 ===== */
.about-section {
    padding: 40px 0;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-bottom: 60px;
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: 20px;
    font-size: 1rem;
    line-height: 1.8;
}

.about-focus h3 {
    font-size: 1.1rem;
    color: var(--accent);
    margin-bottom: 16px;
}

.focus-list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.focus-list li {
    padding: 8px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* 教育经历 */
.education-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
    margin-bottom: 60px;
}

.education-card h3 {
    color: var(--accent);
    margin-bottom: 4px;
}

.education-card .major {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.education-card .level {
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.education-card .period {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Education Tab 切换 */
.edu-tab-nav {
    display: flex;
    gap: 8px;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

.edu-tab-btn {
    padding: 8px 20px;
    border-radius: 20px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

.edu-tab-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.edu-tab-btn.active {
    background: rgba(56, 189, 248, 0.15);
    border-color: var(--accent);
    color: var(--accent);
}

.edu-tab-content {
    display: none;
}

.edu-tab-content.active {
    display: block;
}

/* 时间轴 */
.timeline-section h3 {
    text-align: center;
    font-size: 1.3rem;
    margin-bottom: 32px;
}

.timeline {
    position: relative;
    max-width: 500px;
    margin: 0 auto;
    padding-left: 40px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 15px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border);
}

.timeline-item {
    position: relative;
    margin-bottom: 32px;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -28px;
    top: 6px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--accent);
    border: 3px solid var(--bg-primary);
}

.timeline-year {
    font-size: 1rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 4px;
}

.timeline-event {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ===== Skills 页面 ===== */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    padding-bottom: 60px;
}

.skill-category {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
}

.skill-category h3 {
    font-size: 1rem;
    color: var(--accent);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border);
}

.skill-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.skill-item:last-child {
    margin-bottom: 0;
}

.skill-name {
    font-size: 0.95rem;
    color: var(--text-primary);
}

.skill-stars {
    color: var(--warning);
    font-size: 0.9rem;
    letter-spacing: 2px;
}

.skill-stars .empty {
    color: var(--border);
}

/* ===== Projects 页面 ===== */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    padding-bottom: 60px;
}

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
    transition: all 0.2s;
    display: flex;
    flex-direction: column;
}

.project-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(56, 189, 248, 0.1);
}

.project-card h3 {
    font-size: 1.1rem;
    margin-bottom: 12px;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 12px;
}

.project-tags .tag {
    font-size: 0.75rem;
    padding: 3px 10px;
}

.project-category {
    display: inline-block;
    font-size: 0.8rem;
    color: var(--accent);
    margin-bottom: 12px;
}

.project-summary {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 16px;
    flex: 1;
}

.project-links {
    display: flex;
    gap: 12px;
    margin-top: auto;
}

.project-links a {
    font-size: 0.85rem;
    font-weight: 500;
}

/* ===== 项目详情页 ===== */
.project-detail {
    padding: 40px 0;
    max-width: 800px;
    margin: 0 auto;
}

.project-detail .back-link {
    display: inline-block;
    margin-bottom: 24px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.project-detail .back-link:hover {
    color: var(--accent);
}

.project-detail h1 {
    font-size: 1.8rem;
    margin-bottom: 16px;
}

.detail-section {
    margin-bottom: 36px;
}

.detail-section h2 {
    font-size: 1.2rem;
    color: var(--accent);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
}

.detail-section p {
    color: var(--text-secondary);
    line-height: 1.8;
}

.detail-features {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
}

.detail-features li {
    padding: 8px 12px;
    background: var(--bg-secondary);
    border-radius: var(--radius);
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.detail-features li::before {
    content: '✓ ';
    color: var(--success);
}

/* 架构图 */
.arch-diagram {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    text-align: center;
}

.arch-layer {
    padding: 12px 24px;
    margin: 4px auto;
    background: rgba(56, 189, 248, 0.1);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: var(--radius);
    display: inline-block;
    min-width: 200px;
}

.arch-layer .label {
    font-size: 0.75rem;
    color: var(--text-muted);
    display: block;
}

.arch-layer .value {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent);
}

.arch-arrow {
    color: var(--text-muted);
    font-size: 1.2rem;
    padding: 4px 0;
}

.detail-work {
    list-style: none;
}

.detail-work li {
    padding: 10px 0;
    border-bottom: 1px solid var(--border);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.detail-work li:last-child {
    border-bottom: none;
}

.detail-buttons {
    display: flex;
    gap: 16px;
    margin-top: 32px;
}

/* ===== Competitions 页面 ===== */
.competitions-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    padding-bottom: 60px;
}

.competition-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: all 0.2s;
}

.competition-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}

.competition-card .award-badge {
    display: inline-block;
    padding: 4px 12px;
    background: rgba(234, 179, 8, 0.15);
    color: var(--warning);
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.competition-card h3 {
    font-size: 1.1rem;
    margin-bottom: 4px;
}

.competition-card .subtitle {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 8px;
}

.competition-card .direction {
    color: var(--accent);
    font-size: 0.85rem;
    margin-bottom: 12px;
}

.competition-card .skills {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.competition-card .skills span {
    padding: 4px 10px;
    background: var(--bg-secondary);
    border-radius: 16px;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.skills-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    margin-top: 12px;
}

/* ===== 证书按钮 & 弹窗 ===== */
.cert-section {
    margin-top: 0;
    padding-top: 0;
    border-top: none;
    display: flex;
    justify-content: flex-end;
}

.cert-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 18px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 20px;
    color: var(--text-secondary);
    font-size: 0.82rem;
    font-family: inherit;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.2s;
}

.cert-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(56, 189, 248, 0.08);
}

/* 弹窗 */
.cert-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    z-index: 9999;
    align-items: center;
    justify-content: center;
    cursor: pointer;
}

.cert-modal-content {
    max-width: 90vw;
    max-height: 90vh;
    object-fit: contain;
    border-radius: 4px;
}

.cert-close {
    position: absolute;
    top: 20px;
    right: 32px;
    color: #fff;
    font-size: 2.5rem;
    cursor: pointer;
    transition: 0.2s;
    z-index: 10000;
}

.cert-close:hover {
    color: var(--accent);
}

/* ===== Blog 页面 ===== */
.blog-filters {
    display: flex;
    gap: 8px;
    justify-content: center;
    margin-bottom: 32px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 6px 18px;
    border-radius: 20px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

.filter-btn:hover,
.filter-btn.active {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(56, 189, 248, 0.1);
}

.blog-list {
    max-width: 700px;
    margin: 0 auto;
    padding-bottom: 60px;
}

.blog-item {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    padding: 20px 0;
    border-bottom: 1px solid var(--border);
    gap: 20px;
}

.blog-item:first-child {
    border-top: 1px solid var(--border);
}

.blog-item-content {
    flex: 1;
}

.blog-item h3 {
    font-size: 1rem;
    margin-bottom: 6px;
}

.blog-item h3 a {
    color: var(--text-primary);
}

.blog-item h3 a:hover {
    color: var(--accent);
}

.blog-item .summary {
    color: var(--text-secondary);
    font-size: 0.85rem;
    line-height: 1.5;
}

.blog-item .meta {
    display: flex;
    gap: 10px;
    align-items: center;
    margin-top: 8px;
}

.blog-item .category-tag {
    padding: 2px 10px;
    border-radius: 12px;
    font-size: 0.75rem;
    background: rgba(56, 189, 248, 0.1);
    color: var(--accent);
}

.blog-item .date {
    color: var(--text-muted);
    font-size: 0.8rem;
}

/* ===== Resume 页面 ===== */
.resume-page {
    padding: 40px 0;
    max-width: 800px;
    margin: 0 auto;
}

.resume-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
    flex-wrap: wrap;
    gap: 16px;
}

.resume-header h1 {
    font-size: 1.8rem;
}

.resume-section {
    margin-bottom: 32px;
}

.resume-section h2 {
    font-size: 1.1rem;
    color: var(--accent);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
}

.resume-skill-group {
    margin-bottom: 16px;
}

.resume-skill-group h3 {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.resume-skill-group .tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.resume-project-item {
    margin-bottom: 20px;
}

.resume-project-item h3 {
    font-size: 1rem;
    margin-bottom: 4px;
}

.resume-project-item .summary {
    color: var(--text-secondary);
    font-size: 0.85rem;
    line-height: 1.5;
}

.resume-competition-item {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid var(--border);
    font-size: 0.9rem;
}

.resume-competition-item:last-child {
    border-bottom: none;
}

.resume-competition-item .award {
    color: var(--warning);
    font-weight: 500;
}

/* ===== Contact 页面 ===== */
.contact-page {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: calc(100vh - var(--nav-height) - 60px - 100px);
    padding: 40px 24px;
    text-align: center;
}

.contact-links {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    margin-top: 32px;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 32px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: all 0.2s;
    min-width: 320px;
    max-width: 420px;
    width: 100%;
}

.contact-item:hover {
    border-color: var(--accent);
    transform: translateY(-1px);
}

.contact-item .icon {
    font-size: 1.5rem;
    width: 40px;
    text-align: center;
    flex-shrink: 0;
}

.contact-item > div {
    flex: 1;
}

.contact-item .label {
    font-size: 0.8rem;
    color: var(--text-muted);
    display: block;
}

.contact-item .value {
    font-size: 0.9rem;
    font-weight: 500;
    display: block;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--bg-primary);
        border-bottom: 1px solid var(--border);
        padding: 8px;
        gap: 0;
    }

    .nav-links.show {
        display: flex;
    }

    .nav-links a {
        display: block;
        padding: 12px 16px;
    }

    .menu-toggle {
        display: block;
    }

    .hero-title {
        font-size: 1.8rem;
    }

    .about-grid,
    .skills-grid,
    .projects-grid,
    .competitions-grid {
        grid-template-columns: 1fr;
    }

    .detail-features {
        grid-template-columns: 1fr;
    }

    .contact-item {
        min-width: unset;
        width: 100%;
    }

    .blog-item {
        flex-direction: column;
    }

    .resume-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .terminal-body {
        padding: 16px;
    }

    .terminal-line {
        font-size: 0.8rem;
    }
}