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

:root {
    --primary-color: #ff3333;
    --text-color: #000000;
    --light-color: #ffffff;
}

body {
    font-family: "Helvetica Neue", Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--light-color);
    max-width: 100%;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    text-decoration: none;
    color: var(--text-color);
    transition: opacity 0.3s ease;
}

a:hover {
    opacity: 0.7;
}

/* 头部导航 */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 40px 50px;
    width: 100%;
}

.logo img {
    display: block;
    height: auto;
    max-width: 50%;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 40px;
}

nav ul li a {
    font-size: 14px;
    letter-spacing: 1px;
}

/* 主要内容 */
main {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.main-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.main-image img {
    max-width: 80%;
    max-height: 60vh;
    object-fit: contain;
}

/* 页脚 */
footer {
    padding: 40px 50px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.contact-info p, .address p {
    font-size: 14px;
    letter-spacing: 1px;
}

/* 分隔线 */
.section-divider {
    border: 0;
    height: 1px;
    background-color: #eee;
    margin: 60px auto;
    width: 80%;
}

/* 产品页面 */
.product-content, .about-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 20px;
}

.product-content h2, .about-content h2 {
    font-size: 24px;
    margin-bottom: 10px;
    text-align: center;
}

.product-content h3 {
    font-size: 18px;
    margin-bottom: 30px;
    text-align: center;
    font-weight: normal;
    color: #555;
}

.product-content h4 {
    font-size: 20px;
    margin-top: 30px;
    margin-bottom: 25px;
    color: #333;
}

.product-content .content-description, 
.about-content .contact-info {
    margin-bottom: 80px;
}

.product-content .content-description p,
.about-content .contact-info p {
    font-size: 16px;
    line-height: 1.5;
    margin-bottom: 15px;
    color: #555;
}

.product-content .content-description p:has(+ ul) {
    font-size: 18px;
    font-weight: 500;
    margin-bottom: 10px;
    color: #333;
}

.product-content .content-description ul {
    margin-bottom: 25px;
    padding-left: 25px;
    list-style-type: disc;
}

.product-content .content-description ul li {
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: 12px;
    color: #555;
    padding-left: 5px;
}

.product-content .content-description strong {
    color: #333;
}

.cta-button {
    text-align: center;
    margin: 20px 0;
}

.apply-btn {
    display: inline-block;
    padding: 2px 120px;
    background-color: transparent;
    color: var(--text-color);
    border: 1px solid var(--text-color);
    font-size: 16px;
    text-decoration: none;
    transition: background-color 0.3s, color 0.3s;
}

.apply-btn:hover {
    background-color: var(--text-color);
    color: var(--light-color);
}

/* 汉堡菜单样式 */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 10px;
    z-index: 1000;
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-color);
    position: relative;
    transition: all 0.3s ease;
}

.hamburger:before,
.hamburger:after {
    content: '';
    position: absolute;
    width: 24px;
    height: 2px;
    background: var(--text-color);
    transition: all 0.3s ease;
}

.hamburger:before {
    top: -8px;
}

.hamburger:after {
    top: 8px;
}

/* 菜单激活状态 */
.menu-toggle.active .hamburger {
    background: transparent;
}

.menu-toggle.active .hamburger:before {
    transform: rotate(45deg);
    top: 0;
}

.menu-toggle.active .hamburger:after {
    transform: rotate(-45deg);
    top: 0;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .product-content .content-description {
        padding: 0 20px;
    }
    
    .apply-btn {
        padding: 2px 40px;
        white-space: nowrap;
        max-width: 100%;
    }
    
    header {
        padding: 30px 20px;
        position: relative;
        z-index: 1000;
        background: var(--light-color);
    }
    
    .menu-toggle {
        display: block;
    }
    
    nav ul {
        display: none;
        position: fixed;
        top: 90px; /* header高度 */
        left: 0;
        width: 100%;
        height: calc(100vh - 90px); /* 剩余高度 */
        background: rgba(255, 255, 255, 0.98);
        flex-direction: column;
        padding: 20px 0;
        justify-content: flex-start;
        align-items: center;
        z-index: 999;
        overflow-y: auto;
    }
    
    nav ul.show {
        display: flex;
    }
    
    nav ul li {
        margin: 25px 0;
        text-align: center;
    }
    
    nav ul li a {
        font-size: 18px;
        padding: 15px 30px;
        display: inline-block;
        min-width: 120px;
    }
    
    .main-image img {
        max-width: 90%;
        max-height: 50vh;
    }
    
    footer {
        padding: 30px 20px;
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    .contact-info {
        margin-bottom: 15px;
    }
}

@media (max-width: 576px) {
    header {
        padding: 20px 15px;
    }
    
    .logo img {
        max-width: 40%;
    }
    
    nav ul {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    nav ul li {
        margin: 5px 10px;
    }
    
    .main-image img {
        max-width: 95%;
        max-height: 40vh;
    }
}