/* ===== 顶部：logo+标语 ｜ 电话 ===== */
.header-top{background:var(--c-bg);border-bottom:1px solid var(--c-border)}
.header-top-inner{display:flex;align-items:center;justify-content:space-between;height:92px}
.logo{display:flex;align-items:center;gap:12px}
.logo-icon{width:46px;height:46px;color:var(--c-primary);flex:none}
.logo-name{font-size:26px;font-weight:700;color:var(--c-text);line-height:1.2}
.logo-slogan{font-size:12px;color:var(--c-text-minor);letter-spacing:1px;margin-top:2px}
.header-phone{display:flex;align-items:center;gap:10px;color:var(--c-primary)}
.phone-icon{width:40px;height:40px;flex:none}
.phone-label{font-size:12px;color:var(--c-text-minor)}
.phone-num{font-size:22px;font-weight:700}

/* ===== 电脑端导航 ===== */
.nav-desktop{background:var(--c-primary);position:sticky;top:0;z-index:90;box-shadow:0 2px 8px rgba(0,41,79,.18)}
.nav-desktop>div>ul{display:flex}
.nav-desktop>div>ul>li>a{display:block;padding:16px 24px;color:#fff;font-size:16px;transition:background .3s}
.nav-desktop>div>ul>li>a:hover,.nav-desktop>div>ul>li>a.active{background:var(--c-primary-dark)}

/* 2级+3级下拉 */
.nav-desktop .has-sub{position:relative}
.nav-desktop .sub-nav{position:absolute;left:0;top:100%;min-width:176px;background:var(--c-bg);box-shadow:0 10px 24px rgba(0,20,50,.16);border-radius:0 0 var(--c-radius) var(--c-radius);opacity:0;visibility:hidden;transform:translateY(10px);transition:all .25s ease;z-index:99}
.nav-desktop .has-sub:hover>.sub-nav{opacity:1;visibility:visible;transform:translateY(0)}
.nav-desktop .sub-nav li{width:100%}
.nav-desktop .sub-nav li a{display:block;padding:11px 20px;font-size:14px;color:var(--c-text-sub);background:var(--c-bg);border-bottom:1px solid var(--c-border);white-space:nowrap;transition:all .25s}
.nav-desktop .sub-nav li a:hover{background:var(--c-primary-soft);color:var(--c-primary);padding-left:26px}
.nav-desktop .sub-nav li:last-child a{border-bottom:0}
/* 三级：向右侧弹出 */
.nav-desktop .sub-nav .has-sub>a::after{content:"›";position:absolute;right:14px;color:var(--c-text-minor)}
.nav-desktop .sub-nav .has-sub{position:relative}
.nav-desktop .sub-nav .sub-nav{left:100%;top:-1px;border-radius:var(--c-radius)}
.nav-desktop .sub-nav .sub-nav a{padding-left:18px}
.nav-desktop .sub-nav .sub-nav a:hover{padding-left:24px}

/* ===== 移动端头部+导航 ===== */
.m-header{display:none;background:var(--c-bg);border-bottom:1px solid var(--c-border);position:sticky;top:0;z-index:96}
.m-header-inner{display:flex;align-items:center;justify-content:space-between;height:56px}
.m-header .logo-name{font-size:20px}
.m-nav-btn{width:38px;height:38px;border:1px solid var(--c-border);border-radius:var(--c-radius);background:var(--c-bg);color:var(--c-primary);display:flex;align-items:center;justify-content:center}
.m-nav-btn svg{width:20px;height:20px}
.m-nav-mask{position:fixed;inset:0;background:rgba(0,0,0,.5);opacity:0;visibility:hidden;transition:opacity .3s;z-index:97}
.m-nav-drawer{position:fixed;top:0;right:0;bottom:0;width:280px;background:var(--c-bg);z-index:99;transform:translateX(100%);transition:transform .3s ease;display:flex;flex-direction:column;box-shadow:-6px 0 20px rgba(0,0,0,.12)}
.m-nav-open .m-nav-mask{opacity:1;visibility:visible}
.m-nav-open .m-nav-drawer{transform:translateX(0)}
body.m-nav-open{overflow:hidden}
.m-nav-head{display:flex;align-items:center;justify-content:space-between;padding:16px 18px;border-bottom:1px solid var(--c-border)}
.m-nav-close{width:32px;height:32px;border:0;background:var(--c-bg-section);border-radius:50%;color:var(--c-text-sub);display:flex;align-items:center;justify-content:center}
.m-nav-close svg{width:16px;height:16px}
.m-nav-list{flex:1;padding:10px 0;overflow-y:auto}
.m-nav-list>li>a{display:block;padding:13px 22px;font-size:16px;color:var(--c-text);border-bottom:1px solid var(--c-border)}
.m-nav-list a.active,.m-nav-list a:hover{color:var(--c-primary);background:var(--c-primary-soft)}
/* 移动端 2级+3级 折叠子菜单 */
.m-sub-head{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--c-border)}
.m-sub-head a{flex:1;padding:13px 22px;font-size:16px;color:var(--c-text);border-bottom:0}
.m-sub-toggle{flex:none;width:46px;height:100%;border:0;border-left:1px solid var(--c-border);background:none;color:var(--c-text-minor);font-size:20px;line-height:1;transition:transform .3s}
.m-sub-toggle.open{transform:rotate(45deg);color:var(--c-primary)}
.m-sub-nav{max-height:0;overflow:hidden;transition:max-height .35s ease;background:var(--c-bg-section)}
.m-sub-nav a{display:block;padding:11px 38px;font-size:14px;color:var(--c-text-sub);border-bottom:1px solid var(--c-border)}
.m-sub-nav .m-sub-nav a{padding-left:56px}
.m-sub-nav a:hover{color:var(--c-primary);background:var(--c-primary-soft)}
.m-has-sub.open>.m-sub-nav{max-height:420px}
.m-nav-contact{padding:18px 22px;border-top:1px solid var(--c-border);font-size:13px;color:var(--c-text-sub)}
.m-nav-tel{font-size:20px;font-weight:700;color:var(--c-primary);margin-top:4px}

@media (max-width:768px){
  .header-top{display:none}
  .nav-desktop{display:none}
  .m-header{display:block}
}