/* ====================
   全局样式和变量
   ==================== */

:root {
    /* 亮色模式配色 */
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --accent-color: #0ea5e9;
    --success-color: #10b981;
    --warning-color: #f59e0b;

    /* 中性色 - 亮色 */
    --background: #ffffff;
    --background-alt: #f8fafc;
    --surface: #ffffff;
    --surface-hover: #f1f5f9;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-tertiary: #94a3b8;
    --border-color: #e2e8f0;
    --border-hover: #cbd5e1;

    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;

    /* 字体 */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;

    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* 动画 */
    --transition-fast: 0.15s ease;
    --transition: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* 暗黑模式 */
[data-theme="dark"] {
    --primary-color: #3b82f6;
    --primary-hover: #60a5fa;
    --accent-color: #06b6d4;
    --success-color: #34d399;
    --warning-color: #fbbf24;

    /* 中性色 - 暗色 */
    --background: #0f172a;
    --background-alt: #1e293b;
    --surface: #1e293b;
    --surface-hover: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-tertiary: #64748b;
    --border-color: #334155;
    --border-hover: #475569;

    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.6);
}

/* ====================
   重置和基础样式
   ==================== */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    color: var(--text-primary);
    background-color: var(--background);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color var(--transition), color var(--transition);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

section {
    padding: var(--spacing-2xl) 0;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

/* ====================
   导航栏
   ==================== */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--background);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all var(--transition);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    transition: color var(--transition-fast);
}

.nav-brand:hover {
    color: var(--primary-hover);
}

.nav-menu {
    display: flex;
    gap: var(--spacing-lg);
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    transition: color var(--transition-fast);
    position: relative;
    padding: 0.5rem 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width var(--transition);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* 主题切换按钮 */
.theme-toggle {
    background: var(--surface-hover);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    color: var(--text-primary);
    font-size: 1.25rem;
}

.theme-toggle:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: rotate(180deg);
}

.mobile-toggle {
    display: none;
    background: var(--surface-hover);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    width: 44px;
    height: 44px;
    font-size: 1.25rem;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.mobile-toggle:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* ====================
   Hero Section
   ==================== */

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    position: relative;
    padding-top: 80px;
    background: var(--background);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
    width: 100%;
    max-width: 1200px;
    padding: 0 var(--spacing-md);
}

.hero-text {
    animation: fadeInUp 1s ease;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.hero-title .highlight {
    color: var(--primary-color);
    position: relative;
    display: inline-block;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.btn {
    padding: 0.875rem 2rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    transition: all var(--transition-fast);
    display: inline-block;
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--surface);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeInUp 1s ease 0.2s backwards;
}

.avatar-container {
    position: relative;
    width: 350px;
    height: 350px;
}

.avatar-circle {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: var(--primary-color);
    box-shadow: var(--shadow-xl);
    animation: float 3s ease-in-out infinite;
    border: 4px solid var(--border-color);
}

.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-indicator i {
    font-size: 2rem;
    color: var(--primary-color);
}

/* ====================
   Section 样式
   ==================== */

.section {
    padding: var(--spacing-2xl) 0;
}

.section-alt {
    background-color: var(--background-alt);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    position: relative;
    color: var(--text-primary);
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--primary-color);
    border-radius: var(--radius-full);
}

/* ====================
   About Section
   ==================== */

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.about-card {
    background: var(--surface);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
    text-align: center;
}

.about-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.card-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto var(--spacing-md);
    background: var(--primary-color);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    transition: all var(--transition);
}

.about-card:hover .card-icon {
    transform: scale(1.1);
    background: var(--primary-hover);
}

.about-card h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

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

/* ====================
   Skills Section
   ==================== */

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.skill-category {
    background: var(--surface);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.skill-category:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.skill-category-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.skill-tag {
    padding: 0.5rem 1rem;
    background: var(--background-alt);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    transition: all var(--transition-fast);
    cursor: pointer;
}

.skill-tag:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

/* ====================
   Projects Section
   ==================== */

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.project-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.project-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.project-placeholder {
    width: 100%;
    height: 100%;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    transition: background var(--transition);
}

.project-card:hover .project-placeholder {
    background: var(--primary-hover);
}

.project-content {
    padding: var(--spacing-lg);
}

.project-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.project-description {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.tag {
    padding: 0.25rem 0.75rem;
    background: var(--background-alt);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.project-links {
    display: flex;
    gap: var(--spacing-md);
}

.project-link {
    color: var(--primary-color);
    font-weight: 500;
    transition: color var(--transition-fast);
}

.project-link:hover {
    color: var(--primary-hover);
}

.project-link i {
    margin-right: var(--spacing-xs);
}

/* ====================
   Contact Section
   ==================== */

.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact-intro {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

.social-links {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

.social-link {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-full);
    background: var(--surface);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--primary-color);
    transition: all var(--transition-fast);
}

.social-link:hover {
    transform: translateY(-4px) scale(1.1);
    box-shadow: var(--shadow-lg);
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* ====================
   Footer
   ==================== */

.footer {
    background: var(--background-alt);
    color: var(--text-secondary);
    padding: var(--spacing-lg) 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

/* ====================
   动画
   ==================== */

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    40% {
        transform: translateX(-50%) translateY(-10px);
    }
    60% {
        transform: translateX(-50%) translateY(-5px);
    }
}

/* ====================
   响应式设计
   ==================== */

@media (max-width: 968px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-buttons {
        justify-content: center;
    }

    .avatar-container {
        width: 250px;
        height: 250px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 60px;
        left: 0;
        right: 0;
        background: var(--background);
        border-bottom: 1px solid var(--border-color);
        flex-direction: column;
        padding: var(--spacing-lg);
        box-shadow: var(--shadow-lg);
        transform: translateX(-100%);
        transition: transform var(--transition);
    }

    .nav-menu.active {
        transform: translateX(0);
    }

    .mobile-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
    }

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

    .hero-subtitle {
        font-size: 1.25rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .hero {
        padding-top: 100px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.75rem;
    }

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

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