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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
    line-height: 1.6;
}

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

/* 头部样式 */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 20px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    margin-bottom: 30px;
}

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

.logo h1 {
    font-size: 24px;
    color: #667eea;
    font-weight: 700;
}

.nav {
    display: flex;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
    cursor: pointer;
}

.nav-link:hover {
    color: #667eea;
}

/* 主要内容区域 */
.main-content {
    padding: 20px 0 60px;
}

/* 欢迎横幅 */
.hero {
    text-align: center;
    padding: 60px 20px;
    color: white;
}

.hero-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 15px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
    font-size: 20px;
    opacity: 0.9;
}

/* 通用区块样式 */
.register-section,
.download-section,
.features-section {
    background: white;
    border-radius: 15px;
    padding: 40px;
    margin-bottom: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.section-title {
    font-size: 28px;
    color: #333;
    margin-bottom: 30px;
    text-align: center;
    font-weight: 700;
}

/* 注册表单样式 */
.form-container {
    max-width: 500px;
    margin: 0 auto;
}

.register-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

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

.form-group label {
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
    font-size: 14px;
}

.optional {
    color: #999;
    font-weight: normal;
    font-size: 12px;
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="password"] {
    padding: 12px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
    outline: none;
}

.form-group input:focus {
    border-color: #667eea;
}

.error-message {
    color: #e74c3c;
    font-size: 12px;
    margin-top: 5px;
    min-height: 18px;
    display: block;
}

.checkbox-group {
    margin: 10px 0;
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    cursor: pointer;
    font-size: 14px;
    color: #666;
}

.checkbox-label input[type="checkbox"] {
    margin-right: 8px;
    margin-top: 3px;
    cursor: pointer;
}

.link {
    color: #667eea;
    text-decoration: none;
}

.link:hover {
    text-decoration: underline;
}

/* 按钮样式 */
.btn {
    padding: 14px 30px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    outline: none;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    margin-top: 10px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-download {
    background: #667eea;
    color: white;
    width: 100%;
    margin-top: 15px;
}

.btn-download:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
}

/* 成功消息 */
.success-message {
    background: #d4edda;
    border: 1px solid #c3e6cb;
    color: #155724;
    padding: 15px;
    border-radius: 8px;
    margin-top: 20px;
    text-align: center;
}

/* 下载区域 */
.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.download-card {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 30px 20px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 2px solid transparent;
}

.download-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    border-color: #667eea;
}

.platform-icon {
    font-size: 48px;
    margin-bottom: 15px;
}

.download-card h4 {
    font-size: 20px;
    color: #333;
    margin-bottom: 8px;
}

.download-card p {
    color: #666;
    font-size: 14px;
    margin-bottom: 15px;
}

/* 功能特性 */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 30px;
}

.feature-item {
    text-align: center;
    padding: 20px;
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 15px;
}

.feature-item h4 {
    font-size: 20px;
    color: #333;
    margin-bottom: 10px;
}

.feature-item p {
    color: #666;
    font-size: 14px;
    line-height: 1.6;
}

/* 页脚 */
.footer {
    text-align: center;
    padding: 30px 0;
    color: white;
    opacity: 0.9;
}

/* 响应式设计 - 移动端 */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 15px;
    }

    .nav {
        gap: 20px;
    }

    .hero-title {
        font-size: 28px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .register-section,
    .download-section,
    .features-section {
        padding: 25px 20px;
        margin-bottom: 20px;
    }

    .section-title {
        font-size: 24px;
    }

    .download-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
    }

    .download-card {
        padding: 20px 15px;
    }

    .platform-icon {
        font-size: 36px;
    }

    .features-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .form-container {
        max-width: 100%;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 40px 15px;
    }

    .hero-title {
        font-size: 24px;
    }

    .hero-subtitle {
        font-size: 14px;
    }

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

    .nav {
        flex-direction: column;
        gap: 10px;
    }

    .btn {
        padding: 12px 25px;
        font-size: 14px;
    }
}

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

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

.register-section,
.download-section,
.features-section {
    animation: fadeIn 0.6s ease-out;
}