:root{
    --primary:#ff7a00;
    --primary-dark:#e85d00;
    --text:#222;
    --text-light:#666;
    --bg-gray:#f7f8fa;
    --border:#e8e8e8;
    --white:#fff;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
    font-family:"Microsoft YaHei","PingFang SC","Hiragino Sans GB",sans-serif;
    color:var(--text);
    line-height:1.7;
    background:var(--white);
}
a{text-decoration:none;color:inherit}
img{max-width:100%;display:block}
.container{width:100%;max-width:1140px;margin:0 auto;padding:0 20px}

/* 导航 */
.header{
    position:fixed;top:0;left:0;right:0;z-index:100;
    background:rgba(255,255,255,.96);
    box-shadow:0 2px 12px rgba(0,0,0,.06);
    transition:all .3s;
}
.nav{display:flex;align-items:center;justify-content:space-between;height:68px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;color:var(--primary)}
.brand img{height:40px;width:auto;border-radius:6px}
.nav-menu{display:flex;gap:28px}
.nav-menu a{font-size:15px;color:var(--text);transition:color .2s;position:relative}
.nav-menu a:hover{color:var(--primary)}
.nav-menu a::after{content:"";position:absolute;left:0;bottom:-6px;width:0;height:2px;background:var(--primary);transition:width .3s}
.nav-menu a:hover::after{width:100%}
.nav-toggle{display:none;background:none;border:none;font-size:24px;color:var(--primary);cursor:pointer}

/* Hero */
.hero{
    margin-top:68px;
    background:linear-gradient(135deg,#ff8a1e 0%,#ff6a00 55%,#e85d00 100%);
    color:#fff;text-align:center;padding:120px 20px 110px;
}
.hero h1{font-size:48px;font-weight:800;letter-spacing:4px;margin-bottom:18px;text-shadow:0 2px 14px rgba(0,0,0,.15)}
.hero-sub{font-size:19px;opacity:.95;margin-bottom:14px}
.hero-desc{max-width:720px;margin:0 auto 32px;font-size:15px;opacity:.9;line-height:1.9}
.btn-primary{
    display:inline-block;background:#fff;color:var(--primary-dark);
    padding:13px 38px;border-radius:30px;font-weight:700;font-size:16px;
    transition:transform .2s,box-shadow .2s;
}
.btn-primary:hover{transform:translateY(-3px);box-shadow:0 10px 24px rgba(0,0,0,.18)}

/* 通用 section */
.section{padding:84px 0}
.section-gray{background:var(--bg-gray)}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:32px;font-weight:700;color:var(--text)}
.section-title .line{width:60px;height:4px;background:var(--primary);margin:14px auto 0;border-radius:2px}
.lead{font-size:16px;color:var(--text-light);margin-bottom:18px;text-align:justify}
.lead strong{color:var(--primary-dark);font-weight:700}

/* 数据统计 */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin:40px 0 10px}
.stat{background:var(--white);border:1px solid var(--border);border-radius:12px;padding:30px 16px;text-align:center;box-shadow:0 4px 16px rgba(0,0,0,.04)}
.stat .num{font-size:46px;font-weight:800;color:var(--primary);line-height:1}
.stat .label{margin-top:10px;font-size:15px;color:var(--text-light)}

/* 业务卡片 */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:26px}
.card{background:var(--white);border-radius:14px;padding:38px 28px;text-align:center;box-shadow:0 6px 22px rgba(0,0,0,.06);transition:transform .25s,box-shadow .25s;border:1px solid var(--border)}
.card:hover{transform:translateY(-8px);box-shadow:0 16px 34px rgba(255,122,0,.18)}
.card-icon{width:64px;height:64px;line-height:64px;margin:0 auto 18px;border-radius:50%;background:linear-gradient(135deg,#ff8a1e,#e85d00);color:#fff;font-size:26px;font-weight:700}
.card h3{font-size:21px;margin-bottom:12px;color:var(--text)}
.card p{font-size:14px;color:var(--text-light);line-height:1.8}

/* 旗下公司 */
.subsidiary-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.sub-item{background:var(--bg-gray);border-left:4px solid var(--primary);border-radius:8px;padding:18px 20px;font-size:15px;font-weight:600;color:var(--text);transition:background .2s}
.sub-item:hover{background:#fff4e8}

/* 创始人 */
.founder{display:flex;gap:40px;align-items:center;flex-wrap:wrap}
.founder-photo{flex:0 0 220px;text-align:center}
.avatar{width:200px;height:200px;border-radius:50%;background:linear-gradient(135deg,#ff8a1e,#e85d00);color:#fff;font-size:88px;font-weight:800;display:flex;align-items:center;justify-content:center;box-shadow:0 10px 30px rgba(255,122,0,.3);margin:0 auto}
.founder-info{flex:1;min-width:300px}
.founder-info h3{font-size:28px;color:var(--primary-dark);margin-bottom:6px}
.founder-role{font-size:15px;color:var(--text-light);margin-bottom:16px}
.founder-info p{font-size:15px;color:var(--text-light);margin-bottom:14px;text-align:justify}
.founder-quote{font-size:18px;color:var(--primary-dark);font-weight:700;font-style:italic;border-left:4px solid var(--primary);padding-left:14px}

/* 企业文化 */
.culture-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px}
.culture-item{background:var(--bg-gray);border-radius:12px;padding:28px;text-align:center}
.culture-item h4{font-size:17px;color:var(--primary-dark);margin-bottom:10px}
.culture-item p{font-size:15px;color:var(--text-light);line-height:1.8}

/* 联系我们 */
.contact-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:22px}
.contact-item{background:var(--white);border:1px solid var(--border);border-radius:12px;padding:24px 26px;box-shadow:0 4px 16px rgba(0,0,0,.04)}
.c-label{display:block;font-size:14px;color:var(--text-light);margin-bottom:8px}
.c-value{display:block;font-size:17px;font-weight:600;color:var(--text)}

/* 底部 */
.footer{background:#1f1f1f;color:#bbb;padding:42px 0 34px;text-align:center}
.footer-brand{display:flex;align-items:center;justify-content:center;gap:12px;margin-bottom:16px;color:#fff;font-weight:700;font-size:17px}
.footer-brand img{height:38px;border-radius:6px}
.copyright{font-size:14px;color:#999;margin-bottom:8px}
.beian a{color:var(--primary);font-size:14px;transition:color .2s}
.beian a:hover{color:#ffb066;text-decoration:underline}

/* 返回顶部 */
.back-top{position:fixed;right:24px;bottom:28px;width:46px;height:46px;line-height:46px;text-align:center;background:var(--primary);color:#fff;border-radius:50%;font-size:22px;box-shadow:0 6px 18px rgba(255,122,0,.4);opacity:0;visibility:hidden;transition:all .3s;z-index:99}
.back-top.show{opacity:1;visibility:visible}
.back-top:hover{background:var(--primary-dark)}

/* 响应式 */
@media (max-width:900px){
    .stats,.cards,.subsidiary-grid{grid-template-columns:repeat(2,1fr)}
    .culture-grid,.contact-grid{grid-template-columns:1fr}
    .hero h1{font-size:36px}
}
@media (max-width:640px){
    .nav-menu{position:absolute;top:68px;left:0;right:0;flex-direction:column;background:#fff;gap:0;box-shadow:0 6px 20px rgba(0,0,0,.1);max-height:0;overflow:hidden;transition:max-height .3s}
    .nav-menu.open{max-height:360px}
    .nav-menu a{padding:14px 20px;border-bottom:1px solid var(--border)}
    .nav-toggle{display:block}
    .stats,.cards,.subsidiary-grid{grid-template-columns:1fr}
    .hero h1{font-size:30px}
    .section{padding:60px 0}
    .founder-photo{flex-basis:100%}
}