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

:root {
    --bg: #0a0a12;
    --bg-secondary: rgba(255, 255, 255, 0.04);
    --text: #e6e6f0;
    --text-secondary: #9a9ab0;
    --border: rgba(255, 255, 255, 0.1);
    --accent: #6c63ff;
    --gradient: linear-gradient(135deg, #6c63ff, #e056fd, #ff6b9d);
    --glow: rgba(108, 99, 255, 0.25);
    --card-bg: rgba(255, 255, 255, 0.04);
    --toggle-sun: #f0a500;
    --toggle-moon: #c4c4d8;
}

[data-theme="light"] {
    --bg: #f6f6fb;
    --bg-secondary: rgba(0, 0, 20, 0.04);
    --text: #1b1b2f;
    --text-secondary: #55556e;
    --border: rgba(0, 0, 20, 0.1);
    --accent: #5b50e6;
    --glow: rgba(108, 99, 255, 0.15);
    --card-bg: rgba(255, 255, 255, 0.7);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    background-image:
        radial-gradient(circle at 20% 20%, rgba(108, 99, 255, 0.12), transparent 40%),
        radial-gradient(circle at 80% 30%, rgba(224, 86, 253, 0.08), transparent 40%),
        radial-gradient(circle at 50% 80%, rgba(255, 107, 157, 0.08), transparent 40%);
    background-attachment: fixed;
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background 0.3s ease, color 0.3s ease;
}

/* Chinese pages use a serif (宋体) font stack */
body:lang(zh-Hans) {
    font-family: 'Noto Serif CJK SC', 'Source Han Serif SC', 'Songti SC', 'STSong',
        'SimSun', 'AR PL UMing CN', 'AR PL UMing SC', 'Noto Serif SC', serif;
}

.logo:lang(zh-Hans),
.nav-links:lang(zh-Hans),
.lang-switch:lang(zh-Hans),
.theme-toggle:lang(zh-Hans),
.btn:lang(zh-Hans),
footer:lang(zh-Hans),
.read-more:lang(zh-Hans) {
    font-family: 'Noto Serif CJK SC', 'Source Han Serif SC', 'Songti SC', 'STSong',
        'SimSun', 'AR PL UMing CN', 'AR PL UMing SC', 'Noto Serif SC', serif;
}

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

/* Navbar */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 5%;
    border-bottom: 1px solid var(--border);
    backdrop-filter: blur(10px);
    background: rgba(0, 0, 0, 0.2);
    position: sticky;
    top: 0;
    z-index: 100;
}

[data-theme="light"] .navbar {
    background: rgba(255, 255, 255, 0.6);
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-links a {
    color: var(--text);
    opacity: 0.7;
    transition: opacity 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
    opacity: 1;
}

.nav-links a.active {
    position: relative;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--gradient);
    border-radius: 2px;
}

/* Language Switch */
.lang-switch {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    font-size: 0.85rem;
    font-weight: 600;
}

.lang-switch span {
    opacity: 0.4;
}

.lang-switch a {
    color: var(--text);
    opacity: 0.5;
}

.lang-switch a.active {
    opacity: 1;
    color: var(--accent);
}

/* Theme Toggle */
.theme-toggle {
    background: none;
    border: 1px solid var(--border);
    border-radius: 50%;
    width: 36px;
    height: 36px;
    cursor: pointer;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.2s, border-color 0.2s;
}

.theme-toggle:hover {
    transform: scale(1.1);
    border-color: var(--border);
}

.theme-toggle .icon-sun {
    display: none;
    color: var(--toggle-sun);
}

.theme-toggle .icon-moon {
    display: block;
    color: var(--toggle-moon);
}

[data-theme="light"] .theme-toggle .icon-sun {
    display: block;
}

[data-theme="light"] .theme-toggle .icon-moon {
    display: none;
}

/* Hero */
.hero {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    flex: 1;
    padding: 5rem 5%;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 0.5rem;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: fadeInUp 0.8s ease;
}

.hero .subtitle {
    font-size: 1.3rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    animation: fadeInUp 0.8s ease 0.15s both;
}

.hero .tagline {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 550px;
    margin-bottom: 2.5rem;
    animation: fadeInUp 0.8s ease 0.3s both;
}

.hero-links {
    display: flex;
    gap: 1rem;
    animation: fadeInUp 0.8s ease 0.45s both;
}

.btn {
    padding: 0.75rem 1.75rem;
    border-radius: 8px;
    background: var(--gradient);
    color: #fff;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px var(--glow);
}

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

.btn-outline:hover {
    border-color: transparent;
    box-shadow: inset 0 0 0 1px var(--accent);
}

/* Sections */
.section {
    max-width: 1000px;
    margin: 0 auto;
    padding: 4rem 5%;
    width: 100%;
}

.section-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 2.5rem;
}

.section-header h2 {
    font-size: 2rem;
    white-space: nowrap;
}

.section-header .line {
    flex: 1;
    height: 1px;
    background: var(--border);
}

/* Page Content */
.page-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 4rem 5%;
    width: 100%;
}

.page-content h1 {
    font-size: 2.75rem;
    margin-bottom: 2rem;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

.page-content p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 1.25rem;
}

.bio-section {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
    margin-top: 1.5rem;
    backdrop-filter: blur(10px);
}

.bio-section h2 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text);
}

.bio-section p {
    margin-bottom: 0.75rem;
}

/* Blog */
.post-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.75rem;
    margin-top: 1.5rem;
    backdrop-filter: blur(10px);
    transition: transform 0.2s, border-color 0.2s;
}

.post-card:hover {
    transform: translateY(-2px);
    border-color: rgba(139, 92, 246, 0.4);
}

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

.post-card .post-meta {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    opacity: 0.8;
}

.post-card p {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.inline-code {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 0.1rem 0.35rem;
    font-family: 'SF Mono', Consolas, monospace;
    font-size: 0.85em;
}

.post-card h2 a {
    color: var(--text);
    transition: color 0.2s;
}

.post-card h2 a:hover {
    color: var(--accent);
}

.read-more {
    font-weight: 600;
    opacity: 0.9;
}

.back-link {
    display: inline-block;
    margin-bottom: 1rem;
    opacity: 0.7;
    transition: opacity 0.2s;
}

.back-link:hover {
    opacity: 1;
}

/* Now Page */
.now-items {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.now-item {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    backdrop-filter: blur(10px);
    transition: transform 0.2s, border-color 0.2s;
}

.now-item:hover {
    transform: translateX(4px);
    border-color: rgba(139, 92, 246, 0.4);
}

.now-item h3 {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.now-item p {
    color: var(--text-secondary);
    margin-bottom: 0;
}

.book-carousel {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-top: 0.25rem;
}

.book-stage {
    position: relative;
    width: 172px;
    height: 248px;
    overflow: hidden;
    background: var(--card-bg);
    border-radius: 8px;
}

.now-book {
    position: absolute;
    inset: 0;
    display: block;
    width: 100%;
    height: 100%;
    background: none;
    border: none;
    padding: 0;
    cursor: pointer;
    opacity: 0;
    transition: transform 0.4s cubic-bezier(0.22, 0.61, 0.36, 1), opacity 0.35s ease;
}

.now-book.active {
    opacity: 1;
}

.now-book img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: contain;
    border-radius: 8px;
    transition: transform 0.2s ease;
}

.now-book:hover img {
    transform: scale(1.02);
}

.carousel-btn {
    flex: 0 0 auto;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 50%;
    width: 36px;
    height: 36px;
    cursor: pointer;
    color: var(--text);
    font-size: 1.4rem;
    line-height: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.15s, border-color 0.15s, opacity 0.2s ease, visibility 0.2s ease;
}

.carousel-btn:hover {
    transform: scale(1.1);
    border-color: rgba(139, 92, 246, 0.4);
}

.carousel-btn.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.book-reviews {
    margin-top: 0.6rem;
    max-width: 640px;
}

.book-review {
    display: none;
    padding: 0.9rem 1rem;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.book-review.active {
    display: block;
    animation: fadeInUp 0.25s ease;
}

/* Projects */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.project-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    padding: 0;
    backdrop-filter: blur(10px);
    transition: transform 0.2s, border-color 0.2s;
}

.project-card:hover {
    transform: translateY(-3px);
    border-color: rgba(139, 92, 246, 0.4);
    box-shadow: 0 8px 30px var(--glow);
}

.project-thumb {
    width: 100%;
    display: block;
    border-bottom: 1px solid var(--border);
}

.project-thumb svg {
    display: block;
    width: 100%;
    height: auto;
}

.project-body {
    padding: 1.5rem;
}

.project-body h3 {
    margin-bottom: 0.75rem;
    font-size: 1.15rem;
}

.project-body p {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem 5%;
    border-top: 1px solid var(--border);
    opacity: 0.6;
    font-size: 0.9rem;
    margin-top: auto;
}

footer .socials {
    margin-bottom: 0.75rem;
    display: flex;
    justify-content: center;
    gap: 1.25rem;
}

footer .socials a {
    opacity: 0.7;
    transition: opacity 0.2s;
}

footer .socials a:hover {
    opacity: 1;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive */
@media (max-width: 700px) {
    .hero h1 {
        font-size: 2.25rem;
    }

    .nav-links {
        gap: 1rem;
    }

    .nav-links a {
        font-size: 0.9rem;
    }
}
/* Homepage latest posts */
.home-section {
    max-width: 800px;
    margin: 0 auto;
    padding: 1rem 5% 4rem;
    width: 100%;
}

.home-section .post-card:first-child {
    margin-top: 0;
}

.section-more {
    margin-top: 1.5rem;
}