:root {
    --bg: #ffffff;
    --text: #1a1a1a;
    --subtext: #666666;
    --accent: #000000;
    --border: #e5e5e5;
    --font-serif: 'Noto Serif SC', serif;
    --font-sans: 'Inter', sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: var(--font-sans); background: var(--bg); color: var(--text); line-height: 1.6; }

/* 导航 */
nav {
    display: flex; justify-content: space-between; align-items: center;
    padding: 2rem 5%; max-width: 1400px; margin: 0 auto;
    border-bottom: 1px solid var(--border);
}
.logo { font-family: var(--font-serif); font-size: 1.2rem; letter-spacing: 1px; text-decoration: none; color: var(--text); }
.nav-links { display: flex; gap: 2.5rem; list-style: none; }
.nav-links a { text-decoration: none; color: var(--subtext); font-size: 0.9rem; transition: 0.3s; }
.nav-links a:hover, .nav-links a.active { color: var(--text); }

/* 通用 Hero */
.page-hero {
    padding: 8rem 5% 4rem; max-width: 1400px; margin: 0 auto;
}
.page-hero h1 { font-family: var(--font-serif); font-size: 4rem; line-height: 1.1; margin-bottom: 1.5rem; }
.page-hero p { font-size: 1.2rem; color: var(--subtext); max-width: 600px; }

/* 首页网格 */
.intro-grid {
    display: grid; grid-template-columns: 1fr 1fr; gap: 4rem;
    padding: 0 5% 6rem; max-width: 1400px; margin: 0 auto; align-items: center;
}
.intro-img { width: 100%; height: 500px; object-fit: cover; background: #eee; }
.intro-text h2 { font-family: var(--font-serif); font-size: 2rem; margin-bottom: 1.5rem; }
.intro-text p { margin-bottom: 1rem; color: var(--subtext); }
.btn {
    display: inline-block; margin-top: 1rem; padding: 1rem 2rem;
    background: var(--accent); color: white; text-decoration: none; font-size: 0.9rem;
    transition: 0.3s;
}
.btn:hover { opacity: 0.8; }

/* 关于页布局 */
.about-layout {
    display: grid; grid-template-columns: 1fr 2fr; gap: 4rem;
    padding: 0 5% 6rem; max-width: 1400px; margin: 0 auto;
}
.about-sidebar { border-right: 1px solid var(--border); padding-right: 3rem; }
.stat { margin-bottom: 2rem; }
.stat-num { font-family: var(--font-serif); font-size: 3rem; }
.stat-label { font-size: 0.9rem; color: var(--subtext); }
.about-main p { font-size: 1.1rem; margin-bottom: 1.5rem; }

/* 服务卡片 */
.services-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem; padding: 0 5% 6rem; max-width: 1400px; margin: 0 auto;
}
.service-card { padding: 2rem; border: 1px solid var(--border); transition: 0.3s; }
.service-card:hover { border-color: var(--accent); }
.service-card h3 { font-family: var(--font-serif); font-size: 1.5rem; margin-bottom: 1rem; }
.service-card p { color: var(--subtext); font-size: 0.95rem; }

/* 联系页 */
.contact-layout {
    display: grid; grid-template-columns: 1fr 1fr; gap: 4rem;
    padding: 0 5% 6rem; max-width: 1400px; margin: 0 auto;
}
form { display: flex; flex-direction: column; gap: 1.5rem; }
input, textarea {
    padding: 1rem; border: 1px solid var(--border); background: transparent;
    font-family: var(--font-sans); font-size: 1rem; outline: none;
}
input:focus, textarea:focus { border-color: var(--accent); }
textarea { height: 200px; resize: none; }

footer { text-align: center; padding: 3rem; font-size: 0.8rem; color: var(--subtext); border-top: 1px solid var(--border); }

@media (max-width: 900px) {
    .page-hero h1 { font-size: 2.5rem; }
    .intro-grid, .about-layout, .contact-layout { grid-template-columns: 1fr; }
    .about-sidebar { border-right: none; border-bottom: 1px solid var(--border); padding: 0 0 2rem 0; margin-bottom: 2rem; display: flex; gap: 2rem; }
}