/* 微软简约风：Segoe UI字体、白色/灰调、充足留白、卡片阴影 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

/* 导航栏 */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 60px;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 600;
    color: #0078d4; /* 微软蓝 */
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    text-decoration: none;
    color: #333;
    font-weight: 400;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #0078d4;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* 英雄部分（仅首页） */
.hero {
    height: 100vh;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: 60px; /* 补偿固定header */
}

.hero-content h2 {
    font-size: 3rem;
    font-weight: 300;
    margin-bottom: 1rem;
    color: #333;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    max-width: 600px;
}

.cta-button {
    display: inline-block;
    padding: 12px 24px;
    background: #0078d4;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    font-weight: 600;
    transition: background 0.3s;
}

.cta-button:hover {
    background: #106ebe;
}

/* 通用部分 */
main section {
    padding: 100px 0; /* 增加顶部padding补偿固定header */
}

h2 {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 300;
    margin-bottom: 3rem;
    color: #333;
}

.card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

/* 项目网格 */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    text-align: center;
}

.project-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #0078d4;
}

/* 页脚 */
/* 页脚 - 半透明磨砂灰色（微软风） */
footer {
    background: rgba(255, 255, 255, 0.75);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px); /* Safari 支持 */
    border-top: 1px solid rgba(0, 0, 0, 0.08);
    color: #444;
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
    font-size: 0.95rem;
}

footer p {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 移动端也保持一致美观 */
@media (max-width: 768px) {
    footer {
        padding: 1.5rem 0;
        margin-top: 3rem;
    }
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 60px;
        flex-direction: column;
        background: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hamburger {
        display: flex;
    }

    .hero-content h2 {
        font-size: 2rem;
    }

    main section {
        padding: 80px 0;
    }
}