/* ===== 全局变量 ===== */
:root {
    --primary-50: #eff6ff;
    --primary-100: #dbeafe;
    --primary-200: #bfdbfe;
    --primary-300: #93c5fd;
    --primary-400: #60a5fa;
    --primary-500: #3b82f6;
    --primary-600: #2563eb;
    --primary-700: #1d4ed8;
    --primary-800: #1e40af;
    --primary-900: #1e3a8a;
    
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    --gradient-1: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-2: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-3: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --gradient-4: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
    
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    
    --radius-sm: 0.375rem;
    --radius: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 9999px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ===== 加载动画 ===== */
.loader {
    position: fixed;
    inset: 0;
    background: var(--gradient-1);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loader.hidden {
    opacity: 0;
    visibility: hidden;
}

.loader-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loader p {
    color: white;
    margin-top: 1rem;
    font-size: 1.125rem;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-md);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-lg);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--gray-900);
    font-weight: 700;
    font-size: 1.5rem;
    transition: transform 0.3s ease;
}

.logo:hover {
    transform: scale(1.05);
}

.logo-icon {
    font-size: 2rem;
}

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

.nav-link {
    text-decoration: none;
    color: var(--gray-600);
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-1);
    transition: width 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-600);
}

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

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--gray-700);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* ===== 英雄区域 ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: var(--gradient-1);
    overflow: hidden;
    padding-top: 80px;
}

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

.particle {
    position: absolute;
    width: 10px;
    height: 10px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    animation: float 15s infinite;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) translateX(0);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    90% {
        opacity: 1;
    }
    100% {
        transform: translateY(-100vh) translateX(50px);
        opacity: 0;
    }
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    color: white;
}

.hero-badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 900;
    line-height: 1.2;
    margin-bottom: 1rem;
}

.gradient-text {
    background: var(--gradient-3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-typewriter {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    min-height: 2rem;
}

.typewriter-text {
    color: var(--primary-200);
}

.cursor {
    animation: blink 1s infinite;
    color: white;
}

@keyframes blink {
    0%, 50% { opacity: 1; }
    51%, 100% { opacity: 0; }
}

.hero-description {
    font-size: 1.125rem;
    line-height: 1.8;
    opacity: 0.9;
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-primary {
    background: white;
    color: var(--primary-600);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
}

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

.btn-outline:hover {
    background: white;
    color: var(--primary-600);
}

.btn-block {
    width: 100%;
    justify-content: center;
}

.hero-stats {
    display: flex;
    gap: 3rem;
}

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

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    color: white;
}

.stat-label {
    font-size: 0.875rem;
    opacity: 0.8;
}

.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-image-wrapper {
    position: relative;
    width: 400px;
    height: 400px;
}

.hero-avatar {
    font-size: 20rem;
    animation: float 3s ease-in-out infinite;
}

.floating-card {
    position: absolute;
    background: white;
    padding: 1rem 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    color: var(--gray-700);
    animation: float-card 3s ease-in-out infinite;
}

.card-1 {
    top: 10%;
    left: -20%;
    animation-delay: 0s;
}

.card-2 {
    top: 50%;
    right: -10%;
    animation-delay: 1s;
}

.card-3 {
    bottom: 10%;
    left: 10%;
    animation-delay: 2s;
}

@keyframes float-card {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

.card-icon {
    font-size: 1.5rem;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    color: white;
    opacity: 0.7;
}

.mouse {
    width: 26px;
    height: 40px;
    border: 2px solid white;
    border-radius: 13px;
    margin: 0 auto 0.5rem;
    position: relative;
}

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

@keyframes scroll {
    0% { opacity: 1; transform: translateX(-50%) translateY(0); }
    100% { opacity: 0; transform: translateX(-50%) translateY(12px); }
}

/* ===== 通用区块样式 ===== */
.section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-tag {
    display: inline-block;
    background: var(--primary-100);
    color: var(--primary-700);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--gray-900);
}

/* ===== 关于我 ===== */
.about {
    background: white;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 4rem;
    align-items: center;
}

.about-image {
    display: flex;
    justify-content: center;
}

.image-wrapper {
    position: relative;
    width: 350px;
    height: 350px;
    background: var(--gradient-1);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-xl);
}

.about-avatar {
    font-size: 12rem;
}

.experience-badge {
    position: absolute;
    bottom: -20px;
    right: -20px;
    background: white;
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    text-align: center;
}

.badge-number {
    display: block;
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary-600);
}

.badge-text {
    font-size: 0.875rem;
    color: var(--gray-600);
}

.about-name {
    font-size: 2rem;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 0.5rem;
}

.about-title {
    font-size: 1.25rem;
    color: var(--primary-600);
    margin-bottom: 1.5rem;
}

.about-description {
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: 1rem;
}

.about-info {
    margin: 2rem 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--gray-700);
}

.info-icon {
    font-size: 1.25rem;
}

.about-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

/* ===== 技能专长 ===== */
.skills {
    background: var(--gray-50);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-bottom: 3rem;
}

.skill-category {
    background: white;
    padding: 2rem;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.skill-category:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.skill-category-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--gray-100);
}

.category-icon {
    font-size: 2rem;
}

.skill-category-header h3 {
    font-size: 1.25rem;
    color: var(--gray-900);
}

.skill-list {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.skill-item {
    width: 100%;
}

.skill-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--gray-700);
}

.skill-bar {
    width: 100%;
    height: 8px;
    background: var(--gray-200);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background: var(--gradient-1);
    border-radius: var(--radius-full);
    width: 0;
    transition: width 1s ease;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
}

.skill-tag {
    background: white;
    color: var(--gray-700);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 500;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
}

.skill-tag:hover {
    background: var(--primary-600);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ===== 项目展示 ===== */
.projects {
    background: white;
}

.project-filter {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
}

.filter-btn {
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--gray-200);
    background: white;
    border-radius: var(--radius-full);
    font-weight: 500;
    color: var(--gray-600);
    cursor: pointer;
    transition: all 0.3s ease;
}

.filter-btn:hover,
.filter-btn.active {
    border-color: var(--primary-600);
    background: var(--primary-600);
    color: white;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.project-card {
    background: white;
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.project-image {
    position: relative;
    height: 200px;
    background: var(--gradient-1);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.project-placeholder {
    font-size: 5rem;
}

.project-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

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

.project-link {
    color: white;
    text-decoration: none;
    padding: 0.75rem 1.5rem;
    border: 2px solid white;
    border-radius: var(--radius-full);
    font-weight: 600;
    transition: all 0.3s ease;
}

.project-link:hover {
    background: white;
    color: var(--gray-900);
}

.project-content {
    padding: 1.5rem;
}

.project-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 0.75rem;
}

.project-description {
    color: var(--gray-600);
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 1rem;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.project-tags span {
    background: var(--primary-100);
    color: var(--primary-700);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 500;
}

/* ===== 工作经历 ===== */
.experience {
    background: var(--gray-50);
}

.timeline {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 20px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--primary-200);
}

.timeline-item {
    position: relative;
    padding-left: 60px;
    margin-bottom: 3rem;
}

.timeline-dot {
    position: absolute;
    left: 12px;
    top: 0;
    width: 18px;
    height: 18px;
    background: var(--primary-600);
    border-radius: 50%;
    border: 4px solid white;
    box-shadow: var(--shadow-md);
}

.timeline-content {
    background: white;
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: transform 0.3s ease;
}

.timeline-content:hover {
    transform: translateX(10px);
}

.timeline-date {
    display: inline-block;
    background: var(--primary-100);
    color: var(--primary-700);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.timeline-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 0.25rem;
}

.timeline-company {
    color: var(--primary-600);
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.timeline-description {
    color: var(--gray-600);
    line-height: 1.6;
}

/* ===== 联系我 ===== */
.contact {
    background: white;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 1rem;
}

.contact-description {
    color: var(--gray-600);
    margin-bottom: 2rem;
}

.contact-items {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.contact-icon {
    font-size: 1.5rem;
    width: 50px;
    height: 50px;
    background: var(--primary-100);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-label {
    display: block;
    font-size: 0.875rem;
    color: var(--gray-500);
    margin-bottom: 0.25rem;
}

.contact-item a {
    color: var(--gray-900);
    text-decoration: none;
    font-weight: 500;
}

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

.social-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    background: var(--gray-100);
    border-radius: var(--radius-full);
    color: var(--gray-700);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: var(--primary-600);
    color: white;
    transform: translateY(-3px);
}

.contact-form-wrapper {
    background: var(--gray-50);
    padding: 2rem;
    border-radius: var(--radius-xl);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 600;
    color: var(--gray-700);
}

.form-group input,
.form-group textarea {
    padding: 1rem;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-600);
    box-shadow: 0 0 0 3px var(--primary-100);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* ===== 页脚 ===== */
.footer {
    background: var(--gray-900);
    color: var(--gray-400);
    padding: 3rem 0;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
}

.footer-text {
    line-height: 1.8;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

.footer-links a {
    color: var(--gray-400);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: white;
}

/* ===== 回到顶部 ===== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--primary-600);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
    box-shadow: var(--shadow-lg);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-700);
    transform: translateY(-5px);
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .hero-container,
    .about-grid,
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    
    .hero-visual {
        order: -1;
    }
    
    .hero-image-wrapper {
        width: 300px;
        height: 300px;
    }
    
    .hero-avatar {
        font-size: 15rem;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .projects-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 80px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 2rem;
        gap: 1rem;
        box-shadow: var(--shadow-lg);
        transform: translateY(-150%);
        transition: transform 0.3s ease;
    }
    
    .nav-menu.active {
        transform: translateY(0);
    }
    
    .hamburger {
        display: flex;
    }
    
    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }
    
    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-stats {
        gap: 1.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .timeline::before {
        left: 10px;
    }
    
    .timeline-item {
        padding-left: 40px;
    }
    
    .timeline-dot {
        left: 2px;
    }
}

@media (max-width: 480px) {
    .hero-avatar {
        font-size: 10rem;
    }
    
    .floating-card {
        display: none;
    }
    
    .stat-number {
        font-size: 2rem;
    }
}