/* --- 全局变量与基础设置 --- */
:root {
    --primary-color: #007BFF; /* 希望蓝：专业、信任 */
    --secondary-color: #28a745; /* 活力绿：成长、希望 */
    --text-color: #4A4A4A;      /* 深灰色：柔和、易读 */
    --heading-color: #333333; /* 标题黑 */
    --background-light: #F4F7F9; /* 浅灰背景：增加层次感 */
    --background-white: #FFFFFF;
    --border-radius: 8px;
    --box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

body {
    font-family: 'Noto Sans SC', sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--background-white);
}

.container {
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
}

h1, h2, h3 {
    color: var(--heading-color);
    font-weight: 700;
}

.section-title {
    text-align: center;
    font-size: 2.2rem;
    margin-bottom: 3rem;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background-color: var(--primary-color);
    margin: 0.5rem auto 0;
    border-radius: 2px;
}

/* --- 头部与导航 --- */
.main-header {
    background: var(--background-white);
    padding: 1rem 0;
    border-bottom: 1px solid #e0e0e0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    align-items: center;
}

.main-nav ul li {
    margin-left: 2rem;
}

.main-nav a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* --- 按钮样式 --- */
.button {
    text-decoration: none;
    padding: 0.8rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 700;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    display: inline-block;
}

.button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
}

.button-primary {
    background-color: var(--primary-color);
    color: white;
}

.button-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}


/* --- 英雄区域 --- */
.hero-section {
    /* 请在这里替换为一张明亮、有希望的背景图片 */
    background: linear-gradient(rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0.8)), url('https://images.unsplash.com/photo-1531482615713-2c65776cf473?q=80&w=1470&auto=format&fit=crop') no-repeat center center/cover;
    text-align: center;
    padding: 6rem 0;
}

.hero-section h1 {
    font-size: 3rem;
    max-width: 800px;
    margin: 0 auto 1rem;
}

.hero-section .subtitle {
    font-size: 1.2rem;
    max-width: 600px;
    margin: 0 auto 2rem;
}


/* --- 核心理念区域 --- */
.pillars-section {
    padding: 5rem 0;
    background-color: var(--background-light);
}

.pillars-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.pillar-card {
    background: var(--background-white);
    padding: 2rem;
    text-align: center;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.pillar-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.pillar-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    margin-bottom: 1.5rem;
    /* 临时占位符样式 */
    display: inline-flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
}

.pillar-card h3 {
    margin-bottom: 1rem;
    font-size: 1.4rem;
}


/* --- 影响力聚焦区域 --- */
.impact-section {
    padding: 5rem 0;
}

.impact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.impact-image img {
    width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.impact-content h2 {
    text-align: left;
    margin-bottom: 1.5rem;
}
.impact-content h2::after {
    margin-left: 0;
}

.impact-content p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
}

.impact-content strong {
    color: var(--secondary-color);
    font-weight: 700;
}


/* --- 页脚 --- */
.main-footer {
    background-color: #333333;
    color: #cccccc;
    text-align: center;
    padding: 2rem 0;
}

.main-footer p {
    margin: 0.5rem 0;
}


/* --- 响应式设计 --- */
@media (max-width: 768px) {
    h1 {
        font-size: 2.2rem;
    }
    
    .main-header .container {
        flex-direction: column;
    }
    
    .main-nav ul {
        flex-direction: column;
        width: 100%;
        margin-top: 1rem;
    }
    
    .main-nav ul li {
        margin: 0.5rem 0;
        text-align: center;
    }

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

/* --- 追加到 style.css 文件末尾 --- */

/* --- 子页面的通用样式 --- */
.page-title-section {
    background-color: var(--primary-color);
    color: white;
    text-align: center;
    padding: 4rem 0;
}

.page-title-section h1 {
    color: white;
    font-size: 2.8rem;
    margin: 0;
}

.page-title-section p {
    font-size: 1.2rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 1rem auto 0;
}

.content-section {
    padding: 5rem 0;
}

.content-block {
    max-width: 800px;
    margin: 0 auto 4rem;
    text-align: center;
}

.content-block h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

/* --- 关于我们页：团队样式 --- */
.team-section {
    padding-top: 2rem;
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.team-card {
    background: var(--background-white);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
    overflow: hidden;
    transition: transform 0.3s ease;
}

.team-card:hover {
    transform: translateY(-5px);
}

.team-card img {
    width: 100%;
    height: 300px;
    object-fit: cover;
}

.team-card h3 {
    margin: 1.5rem 0 0.5rem;
    font-size: 1.4rem;
}

.team-card .team-title {
    color: var(--primary-color);
    font-weight: 700;
    margin: 0;
}

.team-card .team-bio {
    padding: 1rem 1.5rem 1.5rem;
    font-size: 0.95rem;
}


/* --- 我们的工作页：项目样式 --- */
.projects-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 3rem;
}

.project-card {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 2rem;
    background: var(--background-white);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    overflow: hidden;
    align-items: center;
}

.project-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.project-content {
    padding: 2rem;
}

.project-content h3 {
    margin-top: 0;
    font-size: 1.6rem;
}

.project-content p {
    margin-bottom: 1.5rem;
}

/* --- 加入我们页：加入方式样式 --- */
.join-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.join-card {
    background: var(--background-light);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    text-align: center;
}

.join-card h3 {
    font-size: 1.6rem;
    margin-top: 0;
}

.join-card p {
    margin-bottom: 2rem;
}

/* --- 联系我们页：特定样式 --- */
.contact-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
}

.contact-form-wrapper h2, .contact-info-wrapper h2 {
    font-size: 1.8rem;
    margin-top: 0;
    margin-bottom: 2rem;
    position: relative;
}

.contact-form-wrapper h2::after, .contact-info-wrapper h2::after {
    content: '';
    display: block;
    width: 40px;
    height: 3px;
    background-color: var(--primary-color);
    margin-top: 0.5rem;
}

/* 表单样式 */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--heading-color);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.8rem 1rem;
    border: 1px solid #ccc;
    border-radius: var(--border-radius);
    font-family: 'Noto Sans SC', sans-serif;
    font-size: 1rem;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.2);
}

/* 直接联系信息样式 */
.info-block {
    display: flex;
    align-items: flex-start;
    margin-bottom: 2rem;
}

.info-block .icon {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-right: 1.5rem;
    margin-top: 0.25rem;
    width: 25px;
    text-align: center;
}

.info-block h4 {
    margin: 0 0 0.25rem;
    font-size: 1.1rem;
    color: var(--heading-color);
}

.info-block p {
    margin: 0;
}

/* 社交链接 */
.social-links {
    margin-top: 2rem;
}

.social-links h4 {
    margin: 0 0 1rem;
}

.social-links a {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--background-light);
    color: var(--primary-color);
    text-decoration: none;
    margin-right: 0.5rem;
    transition: background-color 0.3s, color 0.3s;
}

.social-links a:hover {
    background-color: var(--primary-color);
    color: white;
}

/* --- 响应式调整 --- */
@media (max-width: 992px) {
    .contact-grid {
        grid-template-columns: 1fr;
    }

    .contact-info-wrapper {
        margin-top: 4rem;
    }
}
@media (max-width: 768px) {
    .project-card {
        grid-template-columns: 1fr;
    }
}