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

:root {
    /* 颜色系统 */
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --accent-color: #3b82f6;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;

    /* 阴影系统 */
    --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);
    --transition: all 0.3s ease;

    /* 响应式间距系统 */
    --space-xs: clamp(0.25rem, 0.5vw, 0.5rem);
    --space-sm: clamp(0.5rem, 1vw, 1rem);
    --space-md: clamp(1rem, 2vw, 1.5rem);
    --space-lg: clamp(1.5rem, 3vw, 2.5rem);
    --space-xl: clamp(2rem, 4vw, 4rem);
    --space-2xl: clamp(3rem, 6vw, 6rem);

    /* 响应式字体系统 */
    --font-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
    --font-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
    --font-base: clamp(1rem, 0.9rem + 0.5vw, 1.125rem);
    --font-lg: clamp(1.125rem, 1rem + 0.6vw, 1.25rem);
    --font-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.5rem);
    --font-2xl: clamp(1.5rem, 1.2rem + 1.5vw, 2rem);
    --font-3xl: clamp(1.875rem, 1.5rem + 2vw, 2.5rem);
    --font-4xl: clamp(2.25rem, 1.8rem + 2.5vw, 4rem);

    /* 容器最大宽度 */
    --container-max: 1200px;
    --container-wide: 1400px;

    /* 网格间距 */
    --grid-gap: clamp(1rem, 2vw, 2rem);
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    /* 适配不同缩放比例 */
    -webkit-text-size-adjust: 100%;
    -ms-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "微软雅黑", sans-serif;
    font-size: var(--font-base);
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
    overflow-x: hidden;
    min-height: 100vh;
    /* 适配安全区域（刘海屏等） */
    padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-md);
    width: 100%;
}

/* ==================== 导航栏 ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition);
    /* 适配安全区域 */
    padding-top: env(safe-area-inset-top);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-sm) var(--space-md);
    min-height: 60px;
}

.nav-brand {
    font-size: var(--font-xl);
    font-weight: 700;
    color: var(--primary-color);
    white-space: nowrap;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--space-lg);
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    font-size: var(--font-sm);
    transition: var(--transition);
    position: relative;
    padding: var(--space-xs) 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    transition: var(--transition);
}

/* ==================== 英雄区域 ==================== */
.hero {
    min-height: 100vh;
    min-height: 100dvh; /* 动态视口高度，适配移动端地址栏 */
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    position: relative;
    overflow: hidden;
    padding: var(--space-xl) var(--space-md);
    /* 确保导航栏不遮挡 */
    padding-top: calc(80px + var(--space-xl));
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: var(--space-lg);
    max-width: 900px;
    width: 100%;
}

.hero-title {
    font-size: var(--font-4xl);
    font-weight: 800;
    margin-bottom: var(--space-sm);
    animation: fadeInUp 1s ease;
    letter-spacing: 0.02em;
}

.hero-subtitle {
    font-size: var(--font-2xl);
    margin-bottom: var(--space-sm);
    opacity: 0.95;
    animation: fadeInUp 1s ease 0.2s backwards;
}

.hero-description {
    font-size: var(--font-lg);
    margin-bottom: var(--space-xl);
    opacity: 0.9;
    animation: fadeInUp 1s ease 0.4s backwards;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: var(--space-xl);
    margin-bottom: var(--space-xl);
    animation: fadeInUp 1s ease 0.6s backwards;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
    min-width: 100px;
}

.stat-number {
    font-size: var(--font-3xl);
    font-weight: 800;
    display: block;
    margin-bottom: var(--space-xs);
}

.stat-label {
    font-size: var(--font-sm);
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    animation: fadeInUp 1s ease 0.8s backwards;
    flex-wrap: wrap;
}

.btn {
    padding: var(--space-sm) var(--space-lg);
    border: none;
    border-radius: 8px;
    font-size: var(--font-sm);
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    min-width: 140px;
    min-height: 48px; /* 触摸友好 */
}

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

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

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

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

.hero-scroll {
    position: absolute;
    bottom: var(--space-lg);
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
    font-size: var(--font-2xl);
    opacity: 0.7;
    cursor: pointer;
}

/* ==================== 通用区块样式 ==================== */
.section {
    padding: var(--space-2xl) 0;
}

.section-title {
    font-size: var(--font-3xl);
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--space-sm);
    color: var(--text-dark);
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    font-size: var(--font-base);
    margin-bottom: var(--space-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* ==================== 关于我 - 移动端优先设计 ==================== */
.about {
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8ec 100%);
    padding: var(--space-lg) 0;
}

/* 个人信息卡片 */
.about-card {
    background: var(--bg-white);
    border-radius: 20px;
    padding: var(--space-lg);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.08);
    margin-bottom: var(--space-md);
}

.about-header {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
}

.about-avatar {
    width: 70px;
    height: 70px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
}

.about-avatar i {
    font-size: 1.8rem;
    color: white;
}

.about-info {
    flex: 1;
    min-width: 0;
}

.about-name {
    font-size: var(--font-xl);
    font-weight: 700;
    color: var(--text-dark);
    margin: 0 0 4px 0;
}

.about-title {
    font-size: var(--font-sm);
    color: var(--primary-color);
    font-weight: 600;
    margin: 0 0 4px 0;
}

.about-location {
    font-size: var(--font-xs);
    color: var(--text-light);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 4px;
}

.about-location i {
    font-size: 0.7rem;
}

/* 数据统计 */
.about-stats {
    display: flex;
    justify-content: space-around;
    padding: var(--space-md) 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    margin-bottom: var(--space-md);
}

.about-stat-item {
    text-align: center;
}

.about-stat-num {
    display: block;
    font-size: var(--font-xl);
    font-weight: 800;
    color: var(--primary-color);
    line-height: 1.2;
}

.about-stat-label {
    font-size: var(--font-xs);
    color: var(--text-light);
}

/* 简介 */
.about-bio {
    margin-bottom: var(--space-md);
}

.about-bio p {
    font-size: var(--font-sm);
    color: var(--text-light);
    line-height: 1.7;
    margin: 0;
    text-align: justify;
}

/* 核心能力标签 */
.about-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.about-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: linear-gradient(135deg, #f0f4ff 0%, #e8f0fe 100%);
    border-radius: 20px;
    font-size: var(--font-xs);
    font-weight: 500;
    color: var(--primary-color);
    border: 1px solid rgba(37, 99, 235, 0.1);
}

.about-tag i {
    font-size: 0.7rem;
}

/* 成就亮点 */
.about-achievements {
    background: var(--bg-white);
    border-radius: 20px;
    padding: var(--space-lg);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.08);
}

.achievements-title {
    font-size: var(--font-lg);
    font-weight: 700;
    color: var(--text-dark);
    margin: 0 0 var(--space-md) 0;
    display: flex;
    align-items: center;
    gap: 8px;
}

.achievements-title i {
    color: #f59e0b;
    font-size: 1.1rem;
}

.achievement-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.achievement-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px;
    background: var(--bg-light);
    border-radius: 12px;
    transition: var(--transition);
}

.achievement-item:hover {
    background: linear-gradient(135deg, #f0f4ff 0%, #e8f0fe 100%);
    transform: translateX(4px);
}

.achievement-icon {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.achievement-icon i {
    font-size: 1rem;
    color: white;
}

.achievement-content {
    flex: 1;
    min-width: 0;
}

.achievement-content h4 {
    font-size: var(--font-sm);
    font-weight: 600;
    color: var(--text-dark);
    margin: 0 0 2px 0;
}

.achievement-content p {
    font-size: var(--font-xs);
    color: var(--text-light);
    margin: 0;
    line-height: 1.4;
}

/* ==================== 关于我 - 桌面端适配 ==================== */
@media (min-width: 768px) {
    .about {
        padding: var(--space-xl) 0;
    }

    .about > .container {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: var(--space-lg);
        align-items: start;
    }

    .about-card {
        margin-bottom: 0;
    }

    .about-avatar {
        width: 80px;
        height: 80px;
    }

    .about-avatar i {
        font-size: 2rem;
    }

    .about-name {
        font-size: var(--font-2xl);
    }

    .about-stat-num {
        font-size: var(--font-2xl);
    }

    .achievement-list {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 12px;
    }

    .achievement-item {
        flex-direction: column;
        text-align: center;
        padding: var(--space-md);
    }

    .achievement-icon {
        width: 50px;
        height: 50px;
        margin: 0 auto var(--space-sm);
    }

    .achievement-icon i {
        font-size: 1.2rem;
    }
}

@media (min-width: 1200px) {
    .about > .container {
        grid-template-columns: 2fr 3fr;
    }

    .about-card {
        position: sticky;
        top: 100px;
    }

    .achievement-list {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ==================== 技能特长 - 移动端优先 ==================== */
.skills {
    background: var(--bg-light);
    padding: var(--space-lg) 0;
}

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

.skills-header h2 {
    font-size: var(--font-2xl);
    font-weight: 700;
    color: var(--text-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.skills-header h2 i {
    color: var(--primary-color);
    font-size: 1.5rem;
}

/* 核心技能展示 */
.skills-showcase {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.skill-card {
    background: var(--bg-white);
    border-radius: 16px;
    padding: var(--space-md);
    display: flex;
    align-items: center;
    gap: var(--space-md);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    transition: var(--transition);
}

.skill-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12);
}

.skill-icon {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 1.8rem;
    color: white;
}

.skill-icon.python {
    background: linear-gradient(135deg, #3776ab 0%, #ffd343 100%);
}

.skill-icon.js {
    background: linear-gradient(135deg, #f7df1e 0%, #f0db4f 100%);
}

.skill-icon.php {
    background: linear-gradient(135deg, #777bb3 0%, #8892bf 100%);
}

.skill-icon.ai {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.skill-info {
    flex: 1;
    min-width: 0;
}

.skill-info h4 {
    font-size: var(--font-base);
    font-weight: 600;
    color: var(--text-dark);
    margin: 0 0 8px 0;
}

.skill-level {
    height: 6px;
    background: var(--bg-light);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 6px;
}

.level-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: 3px;
    width: var(--level);
    animation: fillBar 1.5s ease-out;
}

@keyframes fillBar {
    from {
        width: 0;
    }
    to {
        width: var(--level);
    }
}

.skill-desc {
    font-size: var(--font-xs);
    color: var(--text-light);
}

/* 技术标签云 */
.tech-cloud {
    background: var(--bg-white);
    border-radius: 16px;
    padding: var(--space-lg);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

.tech-cloud h3 {
    font-size: var(--font-lg);
    font-weight: 600;
    color: var(--text-dark);
    margin: 0 0 var(--space-md) 0;
    display: flex;
    align-items: center;
    gap: 8px;
}

.tech-cloud h3 i {
    color: var(--primary-color);
    font-size: 1rem;
}

.tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tech-item {
    padding: 8px 14px;
    background: var(--bg-light);
    border-radius: 20px;
    font-size: var(--font-xs);
    font-weight: 500;
    color: var(--text-dark);
    transition: var(--transition);
    border: 1px solid transparent;
}

.tech-item:hover {
    background: linear-gradient(135deg, #f0f4ff 0%, #e8f0fe 100%);
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
}

.tech-item.hot {
    background: linear-gradient(135deg, #fff5f5 0%, #ffe8e8 100%);
    color: #ef4444;
    border-color: rgba(239, 68, 68, 0.2);
}

.tech-item.hot:hover {
    background: linear-gradient(135deg, #fee2e2 0%, #fecaca 100%);
    border-color: #ef4444;
}

/* 桌面端适配 */
@media (min-width: 768px) {
    .skills-showcase {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-md);
    }
}

@media (min-width: 1200px) {
    .skills-showcase {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* ==================== 项目成果 ==================== */
.projects {
    background: var(--bg-white);
}

.projects-filter {
    display: flex;
    justify-content: center;
    gap: var(--space-sm);
    margin: var(--space-xl) 0;
    flex-wrap: wrap;
    padding: 0 var(--space-sm);
}

.filter-btn {
    padding: var(--space-sm) var(--space-md);
    border: 2px solid var(--border-color);
    background: var(--bg-white);
    border-radius: 25px;
    font-size: var(--font-sm);
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-dark);
    white-space: nowrap;
    min-height: 44px; /* 触摸友好 */
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(min(100%, 320px), 1fr));
    gap: var(--grid-gap);
}

/* 当projects是第一个section时，移除顶部间距 */
#projects .projects-grid {
    margin-top: 0;
}

.project-card {
    background: var(--bg-white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

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

.project-image {
    position: relative;
    aspect-ratio: 16 / 9;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    cursor: pointer;
    border-radius: 12px 12px 12px 12px;
}

.project-icon {
    font-size: clamp(2.5rem, 5vw, 4rem);
    color: rgba(255, 255, 255, 0.9);
    transition: var(--transition);
    z-index: 1;
    position: relative;
}

/* 图片缩略图样式 */
.project-thumbnail-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    position: absolute;
    top: 0;
    left: 0;
    transition: var(--transition);
    z-index: 1;
    cursor: pointer;
}

.project-card:hover .project-thumbnail-image {
    opacity: 0.8;
}

/* 视频播放器样式 */
.project-video-thumbnail {
    width: 100%;
    height: 100%;
    object-fit: cover;
    position: absolute;
    top: 0;
    left: 0;
    transition: var(--transition);
    z-index: 1;
    cursor: pointer;
}

.project-card:hover .project-video-thumbnail {
    opacity: 0.8;
}

/* 视频播放按钮覆盖层 - 默认隐藏 */
.video-play-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.2);
    z-index: 3;
    transition: var(--transition);
    cursor: pointer;
    opacity: 0;
    pointer-events: none;
}

.video-play-overlay.visible {
    opacity: 1;
    pointer-events: auto;
}

.video-play-overlay:hover {
    background: rgba(0, 0, 0, 0.3);
}

/* 眼睛预览图标 - 未播放时显示 */
.video-preview-icon {
    position: absolute;
    bottom: 12px;
    right: 12px;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 5;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.video-preview-icon i {
    font-size: 16px;
    color: var(--primary-color);
}

.video-preview-icon:hover {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

/* 播放中隐藏眼睛图标 */
.project-image.playing .video-preview-icon {
    opacity: 0;
    pointer-events: none;
}

.video-play-btn {
    width: 70px;
    height: 70px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.95);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    transition: var(--transition);
}

.video-play-btn i {
    font-size: 28px;
    color: var(--primary-color);
    margin-left: 4px; /* 视觉居中调整 */
}

.video-play-overlay:hover .video-play-btn {
    transform: scale(1.1);
    box-shadow: 0 6px 30px rgba(0, 0, 0, 0.4);
}

/* 视频播放中状态 */
.project-image.playing .video-play-overlay {
    opacity: 0;
    pointer-events: none;
}

.project-image.playing .project-video-thumbnail {
    opacity: 1;
}

/* 暂停时显示播放按钮 */
.project-image.paused .video-play-overlay {
    opacity: 1;
    pointer-events: auto;
}

/* 视频控制条 */
.video-controls {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 8px 12px;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.7));
    display: flex;
    align-items: center;
    gap: 10px;
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: 4;
    border-radius: 0 0 12px 12px;
}

/* 控制条显示状态 - 由JS控制 */
.video-controls.visible {
    opacity: 1;
}

/* 移除原有的hover显示逻辑，改为JS控制 */

.video-progress {
    flex: 1;
    height: 4px;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 2px;
    cursor: pointer;
    position: relative;
}

.video-progress-bar {
    height: 100%;
    background: var(--accent-color);
    border-radius: 2px;
    width: 0%;
    transition: width 0.1s linear;
}

.video-time {
    font-size: 12px;
    color: white;
    min-width: 80px;
    text-align: right;
}

.video-fullscreen-btn {
    background: none;
    border: none;
    color: white;
    cursor: pointer;
    padding: 4px;
    font-size: 16px;
    opacity: 0.8;
    transition: var(--transition);
}

.video-fullscreen-btn:hover {
    opacity: 1;
}

.project-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition);
    z-index: 2;
}

.project-card:hover .project-overlay {
    opacity: 1;
}

.project-card:hover .project-icon {
    transform: scale(1.2);
}

.btn-view {
    padding: 0.75rem 1.5rem;
    background: white;
    color: var(--primary-color);
    border: none;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-view:hover {
    transform: scale(1.05);
}

.project-content {
    padding: var(--space-md);
}

.project-title {
    font-size: var(--font-lg);
    font-weight: 700;
    margin-bottom: var(--space-sm);
    color: var(--text-dark);
    line-height: 1.3;
}

.project-description {
    color: var(--text-light);
    line-height: 1.6;
    margin-bottom: var(--space-sm);
    font-size: var(--font-sm);
}

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

.tag {
    padding: var(--space-xs) var(--space-sm);
    background: var(--bg-light);
    border-radius: 12px;
    font-size: var(--font-xs);
    color: var(--primary-color);
    font-weight: 500;
}

.project-impact {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    color: var(--success-color);
    font-weight: 600;
    font-size: var(--font-xs);
}

.project-impact i {
    font-size: var(--font-sm);
}

/* ==================== 视频展示 ==================== */
.videos {
    background: var(--bg-light);
}

.video-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(min(100%, 320px), 1fr));
    gap: var(--grid-gap);
    margin-top: var(--space-lg);
}

.video-item {
    background: var(--bg-white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.video-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.video-thumbnail {
    width: 100%;
    aspect-ratio: 16/9;
    object-fit: cover;
    cursor: pointer;
    transition: var(--transition);
}

.video-thumbnail:hover {
    opacity: 0.9;
}

.video-info {
    padding: var(--space-md);
}

.video-title {
    font-size: var(--font-base);
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: var(--space-xs);
}

/* ==================== 联系方式 - 移动端优先 ==================== */
.contact {
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8ec 100%);
    padding: var(--space-lg) 0;
}

.contact-card {
    background: var(--bg-white);
    border-radius: 20px;
    padding: var(--space-lg);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.08);
}

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

.contact-header h2 {
    font-size: var(--font-2xl);
    font-weight: 700;
    color: var(--text-dark);
    margin: 0 0 8px 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.contact-header h2 i {
    color: var(--primary-color);
    font-size: 1.5rem;
}

.contact-header p {
    font-size: var(--font-sm);
    color: var(--text-light);
    margin: 0;
}

/* 联系方式列表 */
.contact-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: var(--space-xl);
}

.contact-item-new {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-md);
    background: var(--bg-light);
    border-radius: 12px;
    transition: var(--transition);
    text-decoration: none;
    border: 1px solid transparent;
}

.contact-item-new:hover {
    background: linear-gradient(135deg, #f0f4ff 0%, #e8f0fe 100%);
    border-color: var(--primary-color);
    transform: translateX(4px);
}

.contact-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 1.2rem;
    color: white;
}

.contact-icon.phone {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

.contact-icon.email {
    background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
}

.contact-icon.web {
    background: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
}

.contact-icon.location {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

.contact-text {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.contact-text .label {
    font-size: var(--font-xs);
    color: var(--text-light);
    font-weight: 500;
}

.contact-text .value {
    font-size: var(--font-sm);
    color: var(--text-dark);
    font-weight: 600;
    word-break: break-all;
}

.contact-item-new > i.fa-chevron-right {
    font-size: 1rem;
    color: var(--text-light);
    flex-shrink: 0;
}

/* 桌面端适配 */
@media (min-width: 768px) {
    .contact-list {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }
}

@media (min-width: 1024px) {
    .contact-card {
        padding: var(--space-xl);
    }
}

/* ==================== 页脚 ==================== */
.footer {
    background: var(--text-dark);
    color: white;
    padding: var(--space-lg) 0;
    text-align: center;
    font-size: var(--font-sm);
    /* 适配安全区域 */
    padding-bottom: calc(var(--space-lg) + env(safe-area-inset-bottom));
}

.footer-links {
    margin-top: var(--space-sm);
}

.footer-links a {
    color: white;
    text-decoration: none;
    margin: 0 var(--space-sm);
    transition: var(--transition);
}

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

/* ==================== 视频模态框 ==================== */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    animation: fadeIn 0.3s ease;
    /* 适配安全区域 */
    padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}

.modal-content {
    position: relative;
    margin: var(--space-lg) auto;
    width: min(90%, 1000px);
    max-width: var(--container-max);
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow-xl);
    padding: var(--space-lg);
    animation: slideUp 0.4s ease;
    max-height: calc(100vh - var(--space-xl) * 2);
    overflow-y: auto;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-md);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--border-color);
    gap: var(--space-md);
}

.modal-title {
    font-size: var(--font-2xl);
    font-weight: 700;
    color: var(--text-dark);
    flex: 1;
    min-width: 0;
}

.modal-content video {
    width: 100%;
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    background: #000;
    max-height: 60vh;
    object-fit: contain;
}

.modal-description {
    margin-top: var(--space-md);
    padding: var(--space-md);
    background: var(--bg-light);
    border-radius: 12px;
    color: var(--text-light);
    line-height: 1.8;
    font-size: var(--font-sm);
}

.close {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--bg-light);
    color: var(--text-dark);
    font-size: 24px;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    flex-shrink: 0;
}

.close:hover {
    background: var(--danger-color);
    color: white;
    transform: rotate(90deg);
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@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 ==================== */

/* ========== 超大屏幕 (>= 1400px) - 大桌面显示器 ========== */
@media (min-width: 1400px) {
    .container {
        max-width: var(--container-wide);
    }

    .projects-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ========== 大屏幕 (1200px - 1399px) - 标准桌面 ========== */
@media (max-width: 1399px) and (min-width: 1200px) {
    .projects-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ========== 中等屏幕 (992px - 1199px) - 小桌面/大平板横屏 ========== */
@media (max-width: 1199px) and (min-width: 992px) {
    .projects-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about-content {
        gap: var(--space-lg);
    }
}

/* ========== 平板竖屏/小屏幕 (768px - 991px) ========== */
@media (max-width: 991px) {
    /* 导航栏变为汉堡菜单 */
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 60px;
        flex-direction: column;
        background-color: var(--bg-white);
        width: 100%;
        text-align: center;
        transition: 0.3s ease;
        box-shadow: var(--shadow-md);
        padding: var(--space-lg) 0;
        gap: var(--space-sm);
        max-height: calc(100vh - 60px);
        overflow-y: auto;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-link {
        padding: var(--space-sm);
        display: block;
    }

    /* 项目两列 */
    .projects-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    /* 模态框优化 */
    .modal-content {
        width: 95%;
        margin: var(--space-md) auto;
        padding: var(--space-md);
    }
}

/* ========== 大手机/小平板 (576px - 767px) ========== */
@media (max-width: 767px) {
    /* 英雄区域 */
    .hero {
        padding-top: calc(70px + var(--space-lg));
    }

    .hero-stats {
        gap: var(--space-lg);
    }

    .stat-item {
        min-width: 80px;
    }

    .hero-buttons {
        flex-direction: column;
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }

    .btn {
        width: 100%;
    }

    /* 项目单列 */
    .projects-grid {
        grid-template-columns: 1fr;
    }

    /* 筛选按钮优化 */
    .projects-filter {
        gap: var(--space-xs);
    }

    .filter-btn {
        padding: var(--space-xs) var(--space-sm);
        font-size: var(--font-xs);
    }

    /* 模态框优化 */
    .modal-content {
        margin: var(--space-sm) auto;
        padding: var(--space-sm);
        border-radius: 12px;
    }

    .modal-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-sm);
    }

    .close {
        position: absolute;
        top: var(--space-sm);
        right: var(--space-sm);
    }

    .modal-content video {
        max-height: 40vh;
    }
}

/* ========== 手机 (< 576px) ========== */
@media (max-width: 575px) {
    /* 导航品牌名称缩短 */
    .nav-brand {
        font-size: var(--font-lg);
    }

    /* 英雄区域紧凑 */
    .hero-content {
        padding: var(--space-sm);
    }

    .hero-stats {
        flex-direction: column;
        gap: var(--space-md);
    }

    /* 区块间距减小 */
    .section {
        padding: var(--space-xl) 0;
    }

    /* 项目筛选改为滚动 */
    .projects-filter {
        justify-content: flex-start;
        overflow-x: auto;
        flex-wrap: nowrap;
        padding: 0 var(--space-sm);
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
    }

    .projects-filter::-webkit-scrollbar {
        display: none;
    }

    /* 模态框全屏化 */
    .modal-content {
        width: 100%;
        height: 100%;
        margin: 0;
        border-radius: 0;
        max-height: 100vh;
    }

    .modal-content video {
        border-radius: 8px;
        max-height: 35vh;
    }

    .modal-description {
        padding: var(--space-sm);
    }
}

/* ========== 超小屏幕 (< 375px) ========== */
@media (max-width: 374px) {
    :root {
        --font-base: clamp(0.875rem, 0.85rem + 0.5vw, 1rem);
    }

    .nav-brand {
        font-size: var(--font-base);
    }

    .hero-content {
        padding: var(--space-xs);
    }

    .stat-number {
        font-size: var(--font-2xl);
    }

    .project-content {
        padding: var(--space-sm);
    }
}

/* ========== 横屏模式优化 ========== */
@media (orientation: landscape) and (max-height: 500px) {
    .hero {
        min-height: auto;
        padding: calc(70px + var(--space-md)) var(--space-md) var(--space-md);
    }

    .hero-stats {
        flex-direction: row;
        gap: var(--space-lg);
    }

    .hero-buttons {
        flex-direction: row;
    }

    .modal-content video {
        max-height: 50vh;
    }
}

/* ========== 高 DPI / Retina 屏幕 ========== */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .skill-level {
        height: 5px;
    }

    .nav-toggle span {
        height: 2px;
    }
}

/* ========== 缩放适配 - 基于视口宽度调整根字体 ========== */
@media (max-width: 320px) {
    html {
        font-size: 14px;
    }
}

@media (min-width: 1920px) {
    html {
        font-size: 18px;
    }
}

@media (min-width: 2560px) {
    html {
        font-size: 20px;
    }

    .container {
        max-width: 1800px;
    }
}

/* ========== 减少动画偏好 ========== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }
}

/* ========== 深色模式支持（可选） ========== */
@media (prefers-color-scheme: dark) {
    /* 如需支持深色模式，可在此添加样式 */
}

/* ========== 触摸设备优化 ========== */
@media (hover: none) and (pointer: coarse) {
    /* 移除悬停效果，改用点击 */
    .project-card:hover {
        transform: none;
    }

    .skill-card:hover {
        transform: none;
    }

    .tech-item:hover {
        transform: none;
        background: var(--bg-light);
        color: var(--text-dark);
        border-color: transparent;
    }

    /* 增大触摸目标 */
    .nav-link {
        padding: var(--space-sm) var(--space-md);
    }

    .filter-btn {
        min-height: 48px;
        min-width: 80px;
    }

    .btn {
        min-height: 52px;
    }

    /* 点击时的反馈 */
    .btn:active,
    .filter-btn:active,
    .project-card:active {
        transform: scale(0.98);
        opacity: 0.9;
    }

    .contact-item-new:active {
        transform: scale(0.98);
    }
}

/* ========== 打印样式 ========== */
@media print {
    /* 隐藏非打印元素 */
    .navbar,
    .hero-scroll,
    .projects-filter,
    .btn-view,
    .project-overlay,
    .contact-form,
    .footer,
    .modal {
        display: none !important;
    }

    /* 重置背景和阴影 */
    * {
        background: white !important;
        box-shadow: none !important;
        text-shadow: none !important;
    }

    body {
        font-size: 12pt;
        line-height: 1.5;
        color: black !important;
    }

    .hero {
        min-height: auto;
        padding: 2rem;
        background: white !important;
        color: black !important;
    }

    .hero-title,
    .hero-subtitle,
    .hero-description,
    .stat-number,
    .stat-label {
        color: black !important;
    }

    .section {
        padding: 1.5rem 0;
        page-break-inside: avoid;
    }

    .project-card,
    .skill-card,
    .about-card,
    .contact-card {
        page-break-inside: avoid;
        border: 1px solid #ddd;
    }

    /* 单列布局 */
    .projects-grid {
        grid-template-columns: 1fr;
    }

    /* 显示链接地址 */
    a[href]::after {
        content: " (" attr(href) ")";
        font-size: 0.8em;
        color: #666;
    }

    .nav-link::after {
        content: none;
    }
}