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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

/* 导航栏样式 */
.navbar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0,0,0,0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    color: white;
    font-size: 1.5rem;
    font-weight: bold;
}

.nav-logo i {
    margin-right: 10px;
    font-size: 2rem;
}

.nav-auth {
    display: flex;
    gap: 15px;
}

.btn {
    padding: 10px 20px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    border: none;
    cursor: pointer;
}

.btn-login {
    background: rgba(255,255,255,0.2);
    color: white;
    border: 2px solid rgba(255,255,255,0.3);
}

.btn-login:hover {
    background: rgba(255,255,255,0.3);
    transform: translateY(-2px);
}

.btn-register {
    background: #ff6b6b;
    color: white;
}

.btn-register:hover {
    background: #ff5252;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(255,107,107,0.4);
}

/* 英雄区域样式 */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 120px 0 80px;
    margin-top: 80px;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-description {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 20px;
}

.btn-primary {
    background: #ff6b6b;
    color: white;
    padding: 15px 30px;
    font-size: 1.1rem;
}

.btn-primary:hover {
    background: #ff5252;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(255,107,107,0.3);
}

.btn-secondary {
    background: rgba(255,255,255,0.2);
    color: white;
    border: 2px solid rgba(255,255,255,0.3);
    padding: 15px 30px;
    font-size: 1.1rem;
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.3);
    transform: translateY(-2px);
}

.tool-icon-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.tool-icon {
    background: rgba(255,255,255,0.1);
    border-radius: 20px;
    padding: 30px;
    text-align: center;
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease;
}

.tool-icon:hover {
    transform: translateY(-5px);
}

.tool-icon i {
    font-size: 3rem;
    color: white;
}

/* 功能特性样式 */
.features {
    padding: 80px 0;
    background: white;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    color: #333;
    margin-bottom: 15px;
}

.section-header p {
    font-size: 1.2rem;
    color: #666;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.feature-card {
    background: #fff;
    padding: 40px 30px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

.feature-icon i {
    font-size: 2.5rem;
    color: white;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: #333;
}

.feature-card p {
    color: #666;
    margin-bottom: 20px;
}

.feature-list {
    list-style: none;
    text-align: left;
}

.feature-list li {
    padding: 8px 0;
    color: #555;
    position: relative;
    padding-left: 20px;
}

.feature-list li:before {
    content: '✓';
    color: #667eea;
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* 工具箱用途样式 */
.usage {
    padding: 80px 0;
    background: #f8f9fa;
}

.usage-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.usage-item {
    display: flex;
    align-items: center;
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s ease;
}

.usage-item:hover {
    transform: translateY(-5px);
}

.usage-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 20px;
    flex-shrink: 0;
}

.usage-icon i {
    font-size: 1.8rem;
    color: white;
}

.usage-text h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: #333;
}

.usage-text p {
    color: #666;
    line-height: 1.5;
}

/* 技术优势样式 */
.advantages {
    padding: 80px 0;
    background: white;
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
}

.advantage-item {
    text-align: center;
    padding: 30px;
}

.advantage-item i {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 20px;
}

.advantage-item h4 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: #333;
}

.advantage-item p {
    color: #666;
    line-height: 1.6;
}

/* 页脚样式 */
.footer {
    background: #2c3e50;
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 1.3rem;
    margin-bottom: 20px;
    color: #ecf0f1;
}

.footer-section p {
    color: #bdc3c7;
    line-height: 1.6;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #3498db;
}

.footer-section ul li i {
    margin-right: 10px;
    color: #3498db;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #34495e;
    color: #bdc3c7;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 15px;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .tool-icon-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .usage-item {
        flex-direction: column;
        text-align: center;
    }
    
    .usage-icon {
        margin-right: 0;
        margin-bottom: 15px;
    }
    
    .advantages-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .tool-icon-grid {
        grid-template-columns: 1fr;
    }
    
    .btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }
    
    .feature-card {
        padding: 30px 20px;
    }
}

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

.fade-in {
    animation: fadeInUp 0.8s ease-out;
}

/* 滚动进度条 */
.progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
    z-index: 1001;
    transition: width 0.3s ease;
}