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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
.header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px 0;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.site-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.site-subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* 主内容区域 */
.main-content {
    padding: 40px 0;
}

/* 通用区块标题 */
.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
    position: relative;
    padding-bottom: 15px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 2px;
}

/* APP介绍板块 */
.app-intro {
    background: white;
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.app-intro-content {
    display: flex;
    align-items: center;
    gap: 40px;
    flex-wrap: wrap;
}

.app-logo-section {
    flex: 0 0 auto;
    text-align: center;
}

.app-logo {
    margin-bottom: 15px;
}

.app-logo svg {
    display: block;
    margin: 0 auto;
}

.app-name {
    font-size: 2rem;
    font-weight: 700;
    color: #2c3e50;
    margin-bottom: 5px;
}

.app-version {
    color: #7f8c8d;
    font-size: 0.9rem;
}

.app-description {
    flex: 1;
    min-width: 300px;
}

.app-description .section-title {
    text-align: left;
    font-size: 1.5rem;
    margin-bottom: 20px;
    padding-bottom: 10px;
}

.app-description .section-title::after {
    left: 0;
    transform: none;
}

.description-text {
    font-size: 1.05rem;
    line-height: 1.8;
    color: #555;
    margin-bottom: 20px;
}

.app-features-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.app-features-list li {
    padding: 10px;
    background: #f8f9fa;
    border-radius: 8px;
    font-size: 0.95rem;
}

/* 内容类型板块 */
.preparation-section {
    background: white;
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.preparation-list {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.preparation-item {
    text-align: left;
    padding: 15px 0;
    background: transparent;
    transition: transform 0.3s ease;
}

.preparation-item:hover {
    transform: translateX(5px);
}

.preparation-item h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: #2c3e50;
}

.preparation-item p {
    color: #666;
    font-size: 0.95rem;
    line-height: 1.6;
    margin: 0;
}

/* 温馨提示样式 */
.tips-box {
    display: flex;
    gap: 15px;
    padding: 20px;
    margin-top: 25px;
    background: linear-gradient(135deg, #e3f2fd 0%, #f0f7ff 100%);
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(33, 150, 243, 0.1);
}

.tips-icon {
    font-size: 2rem;
    flex-shrink: 0;
    line-height: 1;
}

.tips-content {
    flex: 1;
}

.tips-title {
    font-size: 1.1rem;
    color: #1976d2;
    margin-bottom: 10px;
    font-weight: 600;
}

.tips-text {
    color: #555;
    font-size: 0.95rem;
    line-height: 1.7;
    margin: 0;
}

/* 美国苹果ID购买入口 */
.purchase-entry {
    margin-top: 40px;
    padding-top: 30px;
    border-top: 2px solid #e9ecef;
}

.purchase-title {
    font-size: 1.4rem;
    color: #2c3e50;
    margin-bottom: 15px;
    font-weight: 700;
}

.purchase-description {
    color: #666;
    font-size: 0.95rem;
    margin-bottom: 25px;
    line-height: 1.7;
}

.purchase-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.purchase-option {
    padding: 25px;
    background: #f8f9fa;
    border-radius: 10px;
    border: 1px solid #e9ecef;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.purchase-option:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
}

.purchase-option h4 {
    font-size: 1.1rem;
    color: #2c3e50;
    margin-bottom: 12px;
    font-weight: 600;
}

.purchase-option p {
    color: #666;
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 20px;
}

.purchase-button {
    display: inline-block;
    padding: 12px 24px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: 600;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    text-align: center;
    width: 100%;
    display: block;
}

.purchase-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.purchase-button.secondary {
    background: #6c757d;
}

.purchase-button.secondary:hover {
    background: #5a6268;
    box-shadow: 0 4px 15px rgba(108, 117, 125, 0.4);
}

/* 下载步骤板块 */
.download-steps {
    background: white;
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.steps-container {
    max-width: 800px;
    margin: 0 auto;
}

.step-item {
    display: flex;
    gap: 30px;
    margin-bottom: 50px;
    align-items: flex-start;
}

.step-item:last-child {
    margin-bottom: 0;
}

.step-number {
    flex: 0 0 50px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.step-content {
    flex: 1;
}

.step-content h3 {
    font-size: 1.4rem;
    margin-bottom: 10px;
    color: #2c3e50;
}

.step-content p {
    color: #666;
    margin-bottom: 20px;
    line-height: 1.7;
}

.step-image {
    margin-top: 15px;
}

.step-img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    max-width: 100%;
}

/* 特色功能板块 */
.features-section {
    background: white;
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

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

.feature-card {
    padding: 30px;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border-radius: 10px;
    border: 1px solid #e9ecef;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    text-align: center;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: #2c3e50;
}

.feature-card p {
    color: #666;
    line-height: 1.7;
    font-size: 0.95rem;
}

/* 注意事项板块 */
.notice-section {
    background: #fff3cd;
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 40px;
}

.notice-section .section-title {
    color: #856404;
}

.notice-section .section-title::after {
    background: #ffc107;
}

.notice-list {
    list-style: none;
    max-width: 700px;
    margin: 0 auto;
}

.notice-list li {
    padding: 15px 0 15px 30px;
    position: relative;
    color: #856404;
    line-height: 1.8;
}

.notice-list li::before {
    content: '⚠️';
    position: absolute;
    left: 0;
    top: 15px;
}

/* 页脚 */
.footer {
    background: #2c3e50;
    color: white;
    padding: 30px 0;
    text-align: center;
}

.footer p {
    margin-bottom: 10px;
    color: #ecf0f1;
}

.footer-note {
    font-size: 0.9rem;
    color: #95a5a6;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .site-title {
        font-size: 2rem;
    }

    .app-intro-content {
        flex-direction: column;
        text-align: center;
    }

    .app-description .section-title {
        text-align: center;
    }

    .app-description .section-title::after {
        left: 50%;
        transform: translateX(-50%);
    }

    .step-item {
        flex-direction: column;
        gap: 20px;
    }

    .step-number {
        align-self: center;
    }

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

    .app-features-list {
        grid-template-columns: 1fr;
    }

    .section-title {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .app-intro,
    .preparation-section,
    .download-steps,
    .features-section,
    .notice-section {
        padding: 25px 20px;
    }

    .site-title {
        font-size: 1.5rem;
    }

    .site-subtitle {
        font-size: 0.9rem;
    }
}

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

/* 图片优化 */
img, svg {
    max-width: 100%;
    height: auto;
}