/* 公司简介页面专用样式 */

/* 主体内容样式 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Arial', 'Microsoft YaHei', sans-serif;
    color: #333;
    line-height: 1.6;
}

/* 公司横幅区域样式 - 建议使用1920x750像素的图片 */
.company-banner {
    width: 100%;
    height: 770px;
    overflow: hidden;
    position: relative;
}

.company-banner img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* 导航按钮区域样式 */
.about-nav-buttons {
    background-color: #f8f8f8;
    padding: 20px 0;
    position: sticky;
    top: 0; /* 修改为0，固定在顶部 */
    z-index: 1000; /* 增加z-index确保在最上层 */
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    width: 100%;
}

/* 确保头部区域也有足够的z-index */
.header {
    position: relative;
    z-index: 1001; /* 比导航按钮高1 */
}

/* 调整内容区域的顶部间距 */
.about-section:first-of-type {
    margin-top: 80px; /* 给导航按钮留出空间 */
}

.nav-buttons-container {
    display: flex;
    justify-content: center;
    max-width: 1200px;
    margin: 0 auto;
    gap: 20px;
}

.nav-button {
    padding: 12px 30px;
    background-color: #ddd;
    color: #333;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.nav-button:hover {
    background-color: #ccc;
}

.nav-button.active {
    background-color: #163762;
    color: white;
}

/* 内容区域通用样式 */
.about-section {
    padding: 60px 0;
    background-color: white;
}

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

.about-section h2 {
    text-align: center;
    color: #163762;
    font-size: 36px;
    margin-bottom: 40px;
    position: relative;
}

.section-content {
    line-height: 1.8;
    font-size: 19px;  /* 文字大小 */
    color: #555;
}

.section-content p {
    margin-bottom: 20px;
}

/* 发展历程按钮样式 */
.history-buttons {
    display: flex;
    justify-content: center;
    margin-bottom: 30px;
    gap: 15px;
}

.history-button {
    padding: 10px 25px;
    background-color: #eee;
    color: #333;
    border: none;
    border-radius: 4px;
    font-size: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.history-button:hover {
    background-color: #ddd;
}

.history-button.active {
    background-color: #163762;
    color: white;
}

/* 发展历程内容区域 */
.history-period {
    display: none;
}

.history-period.active {
    display: block;
}

.history-item {
    margin-bottom: 30px;
    padding-left: 30px;
    position: relative;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.history-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 8px;
    width: 16px;
    height: 16px;
    background-color: #ffcc00;
    border-radius: 50%;
}

.history-item h3 {
    color: #163762;
    font-size: 20px;
    margin-bottom: 10px;
}

.history-item p {
    margin-bottom: 0;
}

/* 董事长致辞区域特殊样式 */
.signature {
    font-family: 'SimSun', 'STKaiti', 'KaiTi', '楷体', '宋体', serif;
    font-style: italic;
    text-align: right;
    margin-top: 30px;
    font-weight: bold;
    font-size: 18px;
}

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

.fade-in-element {
    opacity: 0;
    animation: fadeIn 1s ease-out forwards;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .company-banner {
        height: 600px;
    }
    
    .about-section {
        padding: 50px 0;
    }
    
    .about-section h2 {
        font-size: 32px;
    }
}

@media (max-width: 768px) {
    .company-banner {
        height: 450px;
    }
    
    .nav-buttons-container {
        flex-wrap: wrap;
        gap: 10px;
    }
    
    .nav-button {
        padding: 10px 20px;
        font-size: 14px;
    }
    
    .about-section {
        padding: 40px 0;
    }
    
    .about-section h2 {
        font-size: 28px;
    }
    
    .section-content {
        font-size: 15px;
    }
    
    .history-buttons {
        flex-wrap: wrap;
    }
    
    .history-button {
        padding: 8px 15px;
        font-size: 14px;
    }
    
    .signature {
        font-size: 16px;
    }
}

@media (max-width: 480px) {
    .company-banner {
        height: 350px;
    }
    
    .about-nav-buttons {
        top: 0;
    }
    
    .about-section h2 {
        font-size: 24px;
    }
    
    .section-content {
        font-size: 14px;
    }
    
    .history-item h3 {
        font-size: 18px;
    }
    
    .signature {
        font-size: 15px;
    }
}