/* 全站唯一导航样式入口；Logo、菜单与工具保持单行居中。 */
:root{--home-nav-height:100px}
.nav{position:fixed;inset:0 0 auto;z-index:1000;display:flex;align-items:center;flex-wrap:nowrap;gap:clamp(12px,1.2vw,24px);width:100%;height:var(--home-nav-height);min-height:0;margin:0;padding:0 4%;box-sizing:border-box;border-bottom:1px solid #d7e1efcc;background:rgba(255,255,255,.92);backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px);color:#1d2d46;font-family:"Microsoft YaHei",sans-serif}
.nav *{box-sizing:border-box}.nav a{text-decoration:none;color:inherit}.nav-logo{display:flex;align-items:center;flex:0 1 clamp(220px,20vw,380px);min-width:0;margin:0}.nav-logo-img{display:block;width:100%;max-width:100%;height:auto;max-height:74px;object-fit:contain;padding:0}
.nav-menu{display:flex;align-items:center;justify-content:center;flex:1 1 auto;flex-flow:row nowrap;gap:0;min-width:0;list-style:none;margin:0;padding:0}
.nav-item{position:relative;flex:0 0 auto;margin:0;padding:0;white-space:nowrap;list-style:none;font-size:clamp(13px,.9vw,15px);font-weight:600}.nav-item>a{display:block;padding:14px clamp(5px,.45vw,9px);line-height:1.5;border-radius:4px}.nav-item>a:hover,.nav-item>a:focus-visible{background:#e7effb;color:#164d9a}.nav-item::after{display:none}
.header-tools{display:flex;align-items:center;gap:8px;order:3;flex:0 0 auto;margin:0;padding:0}.header-tools a{padding:7px 10px;white-space:nowrap;font-size:12px;border:1px solid #cfdaea;border-radius:20px;background:#ffffffd9;color:#344b6c}
.nav-search{display:none}.nav-toggle{display:none}
.nav-submenu{display:none;position:absolute;top:100%;left:0;min-width:180px;padding:8px;margin:0;border:1px solid #e1e7f1;border-radius:6px;background:rgba(255,255,255,.98);box-shadow:0 10px 25px #213d641f;opacity:1;visibility:visible;transform:none}
.nav-submenu dl,.nav-submenu dd{margin:0;padding:0}.nav-submenu a{display:block;padding:10px 12px;font-size:14px;font-weight:400;color:#243852;white-space:nowrap}.nav-submenu a:hover{background:#e7effb;color:#164d9a}
@media(min-width:1400px){.nav-item:hover>.nav-submenu,.nav-item:focus-within>.nav-submenu{display:block}}
.subPage{padding-top:calc(var(--home-nav-height) + 30px)}
@media(min-width:1400px) and (max-width:1650px){.nav{gap:14px;padding-left:3%;padding-right:3%}.nav-logo{flex-basis:280px}.nav-item>a{padding:14px 7px}.header-tools{display:flex}}
@media(max-width:1399px){
 .nav{justify-content:space-between;padding:0 5%;gap:16px}
 .nav-logo{flex:0 1 clamp(220px,30vw,380px);max-width:calc(100% - 220px)}
 .header-tools{display:flex;margin-left:auto;order:0}.nav-search{display:none}
 .nav-toggle{display:flex;align-items:center;justify-content:center;flex:0 0 44px;width:44px;height:44px;margin:0;padding:0;border:1px solid #dce4f1;border-radius:6px;background:white;color:#34579f;font-size:25px;cursor:pointer}
 .nav-toggle[aria-expanded="true"]{background:#34579f;color:white}
 .nav-menu{display:none;position:absolute;top:100%;left:0;right:0;flex-direction:column;align-items:stretch;max-height:calc(100svh - var(--home-nav-height));overflow-y:auto;padding:12px 5%;background:rgba(255,255,255,.98);box-shadow:0 12px 24px #1c33521a;border-top:1px solid #e4eaf3}
 .nav-menu.active{display:flex}.nav-item{width:100%;border-bottom:1px solid #edf0f5}.nav-item>a{padding:13px 10px;font-size:16px}
 .nav-submenu{position:static;width:100%;min-width:0;box-shadow:none;background:#f5f7fb;border:0}.nav-item.submenu-open>.nav-submenu{display:block}
}
.nav a:focus-visible,.nav button:focus-visible{outline:2px solid #34579f;outline-offset:3px}

/* 当前栏目及其祖先主菜单：在列表、详情中保持相同选中态。 */
.nav-menu>.nav-item>a[aria-current]{position:relative;color:#2858a4!important;background:#eaf0fb;font-weight:700;box-shadow:inset 0 -3px #345baa}
.nav-submenu a[aria-current]{color:#2858a4!important;background:#eaf0fb;font-weight:600}
@media(max-width:1399px){.nav-menu>.nav-item>a[aria-current]{box-shadow:inset 3px 0 #345baa}}

/* 窄屏把快捷入口移入展开面板，避免挤压 Logo 或直接丢失入口。 */
@media(max-width:599px){
 .nav{gap:10px;padding:0 5%}
 .nav-logo{flex:0 1 320px;max-width:calc(100% - 54px)}
 .nav .header-tools{display:none;position:absolute;top:100%;left:0;right:0;margin:0;padding:14px 5%;height:58px;background:rgba(255,255,255,.98);justify-content:flex-end}
 .nav.menu-open .header-tools{display:flex}
 .nav.menu-open .nav-menu{top:calc(100% + 58px);max-height:calc(100svh - var(--home-nav-height) - 58px)}
}