/* ==================== 基础设置 ==================== */
:root {
    /* 颜色 */
    --primary: #4F8EF7;
    --primary-dark: #3A7AE0;
    --secondary: #F5A623;
    --accent: #FF6B35;
    --bg-dark: #0D1117;
    --bg-card: #161B22;
    --bg-card-hover: #1C2128;
    --text-primary: #E6EDF3;
    --text-secondary: #8B949E;
    --border: #30363D;
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, var(--primary), var(--secondary));
    --gradient-accent: linear-gradient(135deg, var(--primary), var(--accent));
    
    /* 间距 */
    --space-xs: 8px;
    --space-sm: 16px;
    --space-md: 24px;
    --space-lg: 48px;
    --space-xl: 80px;
    --space-2xl: 120px;
    
    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-full: 9999px;
    
    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 20px rgba(0,0,0,0.4);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.5);
    --shadow-glow: 0 0 30px rgba(79, 142, 247, 0.3);
    --shadow-glow-gold: 0 0 30px rgba(245, 166, 35, 0.3);
    
    /* 过渡 */
    --transition-fast: 200ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
    
    /* 布局 */
    --max-width: 1200px;
    --navbar-height: 70px;
}

/* 重置 */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--navbar-height);
}

body {
    font-family: 'Noto Sans SC', 'Inter', system-ui, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* ==================== 通用组件 ==================== */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.section {
    padding: var(--space-2xl) 0;
    position: relative;
}

.tag {
    display: inline-flex;
    align-items: center;
    padding: 6px 14px;
    background: rgba(79, 142, 247, 0.15);
    border: 1px solid rgba(79, 142, 247, 0.3);
    border-radius: var(--radius-full);
    font-size: 13px;
    color: var(--primary);
    transition: all var(--transition-fast);
}

.tag:hover {
    background: rgba(79, 142, 247, 0.25);
    border-color: var(--primary);
}

.highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 500;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: var(--radius-full);
    font-size: 15px;
    font-weight: 500;
    transition: all var(--transition-normal);
}

.btn svg {
    width: 18px;
    height: 18px;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 40px rgba(79, 142, 247, 0.5);
}

.btn-primary:hover svg {
    transform: translateX(4px);
}

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

.btn-outline:hover {
    background: rgba(79, 142, 247, 0.1);
    border-color: var(--primary);
    color: var(--primary);
}

.btn-outline:hover svg {
    transform: translate(2px, -2px);
}

.btn-outline svg {
    transition: transform var(--transition-fast);
}

/* ==================== 导航栏 ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--navbar-height);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.navbar.scrolled {
    background: rgba(13, 17, 23, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.navbar-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-md);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
}

.logo-img {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    object-fit: contain;
}

.logo-icon {
    width: 28px;
    height: 28px;
    color: var(--primary);
}

.logo span {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo-img-small {
    width: 28px;
    height: 28px;
    border-radius: 6px;
    object-fit: contain;
}

.project-logo {
    width: 48px;
    height: 48px;
    object-fit: contain;
    border-radius: 8px;
}

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

.nav-links a {
    position: relative;
    font-size: 15px;
    color: var(--text-secondary);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width var(--transition-fast);
}

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

.nav-links a:hover::after {
    width: 100%;
}

/* 导航链接激活状态 */
.nav-links a.active {
    color: var(--primary);
    font-weight: 500;
}

.nav-links a.active::after {
    width: 100%;
    background: var(--gradient-primary);
    box-shadow: 0 0 10px rgba(79, 142, 247, 0.5);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all var(--transition-fast);
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ==================== Hero区域 ==================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-2xl) var(--space-md);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.particles {
    position: absolute;
    inset: 0;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: var(--primary);
    border-radius: 50%;
    opacity: 0.6;
    animation: float 20s infinite linear;
}

@keyframes float {
    0% {
        transform: translateY(100vh) rotate(0deg);
        opacity: 0;
    }
    10% {
        opacity: 0.6;
    }
    90% {
        opacity: 0.6;
    }
    100% {
        transform: translateY(-100vh) rotate(720deg);
        opacity: 0;
    }
}

.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: var(--primary);
    top: -200px;
    right: -200px;
    animation: pulse 8s ease-in-out infinite;
}

.orb-2 {
    width: 400px;
    height: 400px;
    background: var(--secondary);
    bottom: -100px;
    left: -100px;
    animation: pulse 10s ease-in-out infinite reverse;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.4;
    }
    50% {
        transform: scale(1.1);
        opacity: 0.5;
    }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    animation: fadeInUp 1s ease forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-title {
    font-size: clamp(48px, 10vw, 80px);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--space-md);
}

.title-line {
    display: block;
    color: var(--text-primary);
}

.title-accent {
    display: block;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(18px, 3vw, 24px);
    color: var(--secondary);
    font-weight: 500;
    margin-bottom: var(--space-md);
}

.hero-desc {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-lg);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.scroll-indicator {
    position: absolute;
    bottom: var(--space-lg);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    color: var(--text-secondary);
    font-size: 13px;
    animation: bounce 2s infinite;
}

.mouse {
    width: 24px;
    height: 36px;
    border: 2px solid var(--text-secondary);
    border-radius: 12px;
    position: relative;
}

.wheel {
    width: 4px;
    height: 8px;
    background: var(--text-secondary);
    border-radius: 2px;
    position: absolute;
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
    animation: scroll 2s infinite;
}

@keyframes scroll {
    0%, 100% {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
    50% {
        opacity: 0.5;
        transform: translateX(-50%) translateY(10px);
    }
}

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

/* ==================== 关于我 ==================== */
.about {
    background: linear-gradient(180deg, var(--bg-dark) 0%, var(--bg-card) 100%);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-xl);
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(79, 142, 247, 0.1);
    border-radius: var(--radius-full);
    font-size: 13px;
    font-family: 'Inter', sans-serif;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--primary);
    margin-bottom: var(--space-sm);
}

.section-title {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 700;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-text {
    margin-bottom: var(--space-lg);
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    font-size: 16px;
    line-height: 1.8;
}

.about-text .lead {
    font-size: 20px;
    color: var(--text-primary);
}

.about-skills {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-lg);
}

.skill-category h3 {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: var(--space-sm);
    color: var(--text-primary);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
}

/* ==================== 项目展示 ==================== */
.projects {
    background: var(--bg-card);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--space-lg);
}

.project-card {
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform var(--transition-normal);
}

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

.project-card:hover::before {
    transform: scaleX(1);
}

.project-card:nth-child(2):hover {
    border-color: var(--secondary);
    box-shadow: var(--shadow-lg), var(--shadow-glow-gold);
}

.project-card:nth-child(2):hover::before {
    background: var(--secondary);
}

.project-icon {
    width: 72px;
    height: 72px;
    background: rgba(79, 142, 247, 0.15);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-md);
}

.project-icon.gold {
    background: rgba(245, 166, 35, 0.15);
}

.project-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: var(--space-sm);
}

.project-desc {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.7;
    margin-bottom: var(--space-md);
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: var(--space-md);
}

.project-tags .tag {
    font-size: 12px;
    padding: 4px 10px;
}

.project-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
    padding: var(--space-md);
    background: var(--bg-card);
    border-radius: var(--radius-sm);
}

.feature-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    text-align: center;
}

.feature-item svg {
    width: 20px;
    height: 20px;
    color: var(--primary);
}

.project-card:nth-child(2) .feature-item svg {
    color: var(--secondary);
}

.feature-item span {
    font-size: 12px;
    color: var(--text-secondary);
}

/* ==================== 特色功能 ==================== */
.features {
    background: linear-gradient(180deg, var(--bg-card) 0%, var(--bg-dark) 100%);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-lg);
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    text-align: center;
    transition: all var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: var(--primary);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: 72px;
    height: 72px;
    background: rgba(79, 142, 247, 0.1);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--space-md);
    color: var(--primary);
    transition: all var(--transition-normal);
}

.feature-card:hover .feature-icon {
    background: rgba(79, 142, 247, 0.2);
    transform: scale(1.1);
}

.feature-icon svg {
    width: 36px;
    height: 36px;
}

.feature-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: var(--space-sm);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.7;
}

/* ==================== 联系方式 ==================== */
.contact {
    background: var(--bg-card);
    text-align: center;
}

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

.contact h2 {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 700;
    margin-bottom: var(--space-md);
}

.contact p {
    color: var(--text-secondary);
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: var(--space-lg);
}

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

.contact-item {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 12px 24px;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: var(--radius-full);
    color: var(--text-primary);
    transition: all var(--transition-normal);
}

.contact-item:hover {
    border-color: var(--primary);
    background: rgba(79, 142, 247, 0.1);
}

.contact-item svg {
    width: 20px;
    height: 20px;
    color: var(--primary);
}

/* ==================== 页脚 ==================== */
.footer {
    padding: var(--space-lg) 0;
    border-top: 1px solid var(--border);
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 18px;
    font-weight: 600;
}

.footer-brand .logo-icon {
    width: 24px;
    height: 24px;
    color: var(--primary);
}

.footer-copy {
    color: var(--text-secondary);
    font-size: 14px;
}

/* ==================== 动画 ==================== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
    :root {
        --space-xl: 60px;
        --space-2xl: 80px;
    }
    
    .nav-links {
        position: fixed;
        top: var(--navbar-height);
        left: 0;
        right: 0;
        background: rgba(13, 17, 23, 0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        padding: var(--space-lg);
        gap: var(--space-md);
        border-bottom: 1px solid var(--border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-normal);
    }
    
    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .hero {
        min-height: calc(100vh - var(--navbar-height));
        padding-top: calc(var(--navbar-height) + var(--space-lg));
    }
    
    .scroll-indicator {
        display: none;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .project-features {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .feature-item span {
        font-size: 11px;
    }
    
    .contact-links {
        flex-direction: column;
    }
    
    .contact-item {
        width: 100%;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .project-features {
        grid-template-columns: 1fr;
        gap: var(--space-sm);
    }
    
    .feature-item {
        flex-direction: row;
        justify-content: flex-start;
        gap: 10px;
    }
    
    .feature-item span {
        font-size: 14px;
    }
}