/* =========================================
   智目科技 - 公共样式表 (common.css)
   适用于：index.html, about.html, join.html, contact.html
   ========================================= */

/* --- 1. CSS 变量定义 --- */
:root {
    --primary-color: #00d2b8;
    /* 品牌青 */
    --secondary-color: #333333;
    /* 次要文字/深色 */
    --dark-bg: #1a1a1a;
    /* 深色背景 */
    --light-bg: #f9f9f9;
    /* 浅色背景 */
    --text-main: #333333;
    /* 主要文字 */
    --text-sub: #666666;
    /* 次要文字/灰色 */
    --white: #ffffff;
    /* 白色 */
    --transition: all 0.3s ease;
    /* 通用过渡效果 */
    --box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    /* 通用阴影 */
}

/* --- 2. 全局重置与基础样式 --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

body {
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
    background-color: var(--white);
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-color);
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* --- 3. 通用布局容器 --- */
.container {
    max-width: 1300px;
    margin: 0 auto;
    /* padding: 0 20px; */
    width: 100%;
}

/* --- 4. 通用组件样式 --- */

/* 章节标题 */
.section-title {
    text-align: center;
    font-size: 32px;
    font-weight: bold;
    margin-bottom: 40px;
    color: var(--text-main);
    position: relative;
}

/* 可选：标题下划线装饰 (如需) */
.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: var(--primary-color);
    margin: 15px auto 0;
}

/* 按钮 - 实心 */
.btn {
    display: inline-block;
    padding: 12px 30px;
    background: var(--primary-color);
    color: var(--white);
    border-radius: 4px;
    font-weight: 500;
    border: 1px solid var(--primary-color);
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
}

.btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 210, 184, 0.3);
}

/* 按钮 - 描边 */
.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-color);
    color: var(--white);
}

/* --- 5. 导航栏样式 (Header) --- */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    z-index: 1000;
    height: 70px;
    display: flex;
    align-items: center;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 1300px;
    margin: 0 auto;
    /* padding: 0 20px; */
}

.logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--text-main);
}

.logo img {
    width: 130px;
}


.nav-links {
    display: flex;
    gap: 50px;
}

.nav-links a {
    font-size: 0.95rem;
    color: var(--text-main);
    font-weight: 500;
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-color);
}

/* 激活状态或悬停 */
.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-color);
}

/* 简单的下划线动画效果 (可选) */
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

/* --- 6. 页脚样式 (Footer) --- */
/* --- Footer (已按效果图严格修改) --- */
footer {
    background-color: #0f1115;
    /* 深色背景 */
    color: #888;
    padding: 90px 0 60px;
    font-size: 0.9rem;
    position: relative;
    overflow: hidden;
}

/* 背景图与遮罩 */
footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('../images/footer/footter_bg.jpg');
    background-size: cover;
    background-position: center;
    z-index: 0;
}

footer>.container {
    position: relative;
    z-index: 1;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr 2.2fr 1.6fr;
    /* 左中右比例 */
    gap: 40px;
    margin-bottom: 40px;
    align-items: start;
}

/* 左侧：品牌信息 */
.footer-brand .footer-logo {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
    color: white;
    font-size: 1.4rem;
    font-weight: bold;
}

.footer-brand .footer-logo img {
    height: 50px;
}

.footer-brand p {
    line-height: 1.6;
    margin-bottom: 10px;
}

.copyright-info {
    font-size: 0.8rem;
    color: #666;
}

/* 中间：联系方式 */
.footer-contact h4 {
    color: white;
    margin-bottom: 20px;
    font-size: 1.1rem;
    font-weight: 600;
}

.contact-list {
    list-style: none;
}

.contact-list li {
    margin-bottom: 15px;
    display: flex;
    align-items: flex-start;
    color: #888;
}

.contact-list li i {
    margin-right: 12px;
    color: var(--primary-color);
    margin-top: 4px;
    width: 16px;
    text-align: center;
}

.contact-list li a {
    color: #888;
    transition: 0.3s;
}

.contact-list li a:hover {
    color: var(--primary-color);
}

/* 右侧：导航与社交 */
.footer-nav-social h4 {
    color: white;
    margin-bottom: 20px;
    font-size: 1.1rem;
    font-weight: 600;
}

.footer-nav-links {
    display: flex;
    flex-wrap: wrap;
    gap: 49px;
    margin-bottom: 65px;
}

.footer-nav-links a {
    color: #fff;
    font-size: 0.9rem;
}

.footer-nav-links a:hover {
    color: var(--primary-color);
}

.social-icons {
    display: flex;
    gap: 36px;
    justify-content: right;
}

.social-wrapper {
    position: relative;
    display: inline-block;
}

.social-icons a {
    color: #888;
    font-size: 1.2rem;
    transition: 0.3s;
    position: relative;
}

.social-icons a img {
    width: 24px;
    height: 24px;
}

.social-icons a:hover {
    color: var(--primary-color);
    transform: translateY(-3px);
}

/* 二维码弹窗 */
.qr-popup {
    width: 140px;
    position: absolute;
    bottom: 46px;
    left: 50%;
    transform: translateX(-50%) translateY(10px);
    background: white;
    padding: 10px;
    border-radius: 8px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    pointer-events: none;
    z-index: 10;
}

.qr-popup img {
    width: 120px;
    height: 120px;
    display: block;
}

.qr-popup::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    border-width: 8px;
    border-style: solid;
    border-color: white transparent transparent transparent;
}

.social-wrapper:hover .qr-popup {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.footer-bottom {
    border-top: 1px solid #222;
    padding-top: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    color: #666;
}

@media (max-width: 768px) {
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .contact-list li {
        justify-content: center;
    }

    .footer-nav-links {
        justify-content: center;
    }

    .social-icons {
        justify-content: center;
    }

    .footer-bottom {
        flex-direction: column;
        gap: 10px;
        text-align: center;
    }
}