/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 1rem 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    text-decoration: none;
}

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

.nav-links a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

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

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.menu-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-dark);
    transition: all 0.3s;
}

/* Hero 区域 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
    padding: 2rem;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
}

.hero-content .highlight {
    background: linear-gradient(90deg, #fbbf24, #f59e0b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-content .subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s;
}

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

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

/* 关于我 */
.about {
    padding: 6rem 0;
    background: var(--bg-light);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-dark);
}

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

.about-text {
    font-size: 1.125rem;
    color: var(--text-light);
    text-align: center;
    margin-bottom: 3rem;
}

.skills {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.skill-item {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.skill-item h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.skill-item p {
    color: var(--text-light);
}

/* 项目展示 */
.projects {
    padding: 6rem 0;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--bg-white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s;
    border: 1px solid var(--border-color);
}

.project-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.project-header {
    padding: 1.5rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.project-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.project-description {
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.95rem;
}

.project-body {
    padding: 1.5rem;
}

.project-meta {
    margin-bottom: 1rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-light);
    font-size: 0.9rem;
}

.meta-item .label {
    font-weight: 600;
    color: var(--text-dark);
    min-width: 80px;
}

.tech-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.tech-tag {
    background: var(--bg-light);
    color: var(--primary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

.project-links {
    display: flex;
    gap: 1rem;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s;
}

.project-link:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

.project-link.secondary {
    background: var(--bg-light);
    color: var(--text-dark);
}

.project-link.secondary:hover {
    background: var(--border-color);
}

/* 联系我 */
.contact {
    padding: 6rem 0;
    background: var(--bg-light);
}

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

.contact-text {
    font-size: 1.125rem;
    color: var(--text-light);
    margin-bottom: 2rem;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

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

.contact-link .icon {
    font-size: 1.25rem;
}

/* 页脚 */
.footer {
    padding: 2rem 0;
    background: var(--text-dark);
    color: white;
    text-align: center;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow);
    }

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

    .menu-toggle {
        display: flex;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

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

    .contact-links {
        flex-direction: column;
        gap: 1rem;
    }
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

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

.project-card {
    animation: fadeIn 0.5s ease-out;
}