/* nav-b.css — B 内容型共享导航层（S1-2 公共层抽取）
   适用：solutions / support / about / news / industry / exhibition / marketing
        / careers×4 / inquiry / privacy 等 B 类页面
   依赖各页内联 :root 定义的变量（--ink/--line/--pur/--surf/--r-sm/--r-md/--nav-h/--max）。
   本文件为并集超集：含当前页高亮 .active 等规则，仅对显式加类元素生效，对未用到的页无副作用。
   桌面→移动切换断点固定 900px（B 型）。页面专属 hero/section/footer CSS 仍保留在各页内联。 */

nav{position:sticky;top:0;z-index:200;height:var(--nav-h);background:rgba(255,255,255,0.96);backdrop-filter:blur(16px);border-bottom:0.5px solid var(--line);display:flex;align-items:center;}
.nav-inner{max-width:var(--max);width:100%;margin:0 auto;padding:0 2rem;display:flex;align-items:center;justify-content:space-between;}
.logo{display:flex;align-items:center;gap:10px;text-decoration:none;flex-shrink:0;}
.logo-mark{width:36px;height:36px;border-radius:8px;background:#e02020;display:flex;align-items:center;justify-content:center;font-size:15px;font-weight:700;color:#fff;letter-spacing:-0.5px;}
.logo-text{font-size:17px;font-weight:700;color:var(--ink);}
.logo-sub{font-size:12px;color:var(--ink-3);letter-spacing:0.08em;margin-top:1px;}
.nav-links{display:flex;align-items:center;gap:8px;}
.nav-link{font-size:15px;color:var(--ink-3);text-decoration:none;padding:6px 12px;border-radius:var(--r-sm);transition:all .15s;}
.nav-link:hover{color:var(--ink);background:var(--surf);}
.nav-link.active{color:var(--pur);font-weight:600;}
.nav-inquiry{font-size:15px;font-weight:600;color:#fff;background:#e02020;border:none;border-radius:9px;padding:9px 18px;cursor:pointer;text-decoration:none;transition:background .15s;margin-left:8px;}
.nav-inquiry:hover{background:#b81818;}

/* 汉堡按钮 */
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:4px;}
.nav-toggle span{display:block;width:22px;height:2px;background:var(--ink);border-radius:2px;transition:all .25s;}
.nav-toggle.open span:nth-child(1){transform:translateY(7px) rotate(45deg);}
.nav-toggle.open span:nth-child(2){opacity:0;}
.nav-toggle.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg);}

/* 移动端抽屉 */
.nav-drawer{display:none;position:fixed;top:var(--nav-h);left:0;right:0;bottom:0;background:rgba(255,255,255,0.98);backdrop-filter:blur(20px);z-index:190;padding:1.5rem;overflow-y:auto;}
.nav-drawer.open{display:block;}
.nav-drawer .nav-links{display:flex;flex-direction:column;align-items:flex-start;gap:0;}
/* 修复：抽屉内菜单容器强制显示，避免被各页 @480 的 .nav-links{display:none} 误伤 */
.nav-drawer .nav-link{display:block;padding:1rem 0;font-size:20px;font-weight:600;color:var(--ink);border-bottom:0.5px solid var(--line);width:100%;}

/* 下拉菜单（资讯中心 / 职业发展） */
.has-dropdown{position:relative;display:inline-flex;align-items:center;}
.dropdown-trigger{display:inline-flex;align-items:center;gap:4px;cursor:default;font-size:15px;color:var(--ink-3);padding:6px 12px;border-radius:var(--r-sm);transition:all .15s;}
.dropdown-trigger.active{color:var(--pur);font-weight:600;}
.dropdown-trigger::after{content:'';width:5px;height:5px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg);margin-top:-3px;margin-left:2px;transition:transform .2s;opacity:0.6;}
.has-dropdown:hover .dropdown-trigger{color:var(--ink);background:var(--surf);}
.has-dropdown:hover .dropdown-trigger.active{color:var(--pur);}
.has-dropdown:hover .dropdown-trigger::after{transform:rotate(225deg);margin-top:1px;}
.dropdown-menu{position:absolute;top:100%;left:50%;transform:translateX(-50%) translateY(8px);min-width:180px;background:#fff;border:0.5px solid var(--line);border-radius:var(--r-md);box-shadow:0 8px 28px rgba(0,0,0,0.10);padding:8px;opacity:0;visibility:hidden;transition:all .2s;z-index:210;}
.dropdown-menu::before{content:'';position:absolute;top:-12px;left:0;right:0;height:12px;}
.has-dropdown:hover .dropdown-menu{opacity:1;visibility:visible;transform:translateX(-50%) translateY(4px);}
.dropdown-menu a{display:flex;align-items:center;gap:9px;padding:10px 12px;font-size:16px;color:var(--ink-2);text-decoration:none;border-radius:var(--r-sm);transition:all .15s;white-space:nowrap;}
.dropdown-menu a:hover{background:var(--surf);color:var(--pur);}
.dropdown-menu a.active{color:var(--pur);font-weight:600;background:rgba(224,32,32,0.08);}
.dropdown-menu a .dd-ico{font-size:17px;width:18px;text-align:center;flex-shrink:0;}

/* 移动端抽屉子菜单 */
.nav-drawer .has-sub > .drawer-sub-trigger{display:flex;align-items:center;justify-content:space-between;padding:1rem 0;font-size:18px;font-weight:600;color:var(--ink);cursor:pointer;border-bottom:0.5px solid var(--line);}
.nav-drawer .has-sub > .drawer-sub-trigger::after{content:'';width:8px;height:8px;border-right:2px solid var(--ink-3);border-bottom:2px solid var(--ink-3);transform:rotate(45deg);transition:transform .25s;}
.nav-drawer .has-sub.open > .drawer-sub-trigger::after{transform:rotate(-135deg);}
.nav-drawer .drawer-sub{max-height:0;overflow:hidden;transition:max-height .3s ease;}
.nav-drawer .has-sub.open .drawer-sub{max-height:400px;}
.nav-drawer .drawer-sub a{display:flex;align-items:center;gap:10px;padding:0.85rem 0 0.85rem 1.2rem;font-size:18px;font-weight:500;color:var(--ink-2);border-bottom:0.5px solid var(--line);}
.nav-drawer .drawer-sub a:hover{color:var(--pur);}
.nav-drawer .drawer-sub a.active{color:var(--pur);font-weight:600;}
.nav-drawer .drawer-sub a .dd-ico{font-size:18px;}

@media(max-width:900px){nav .nav-links,.nav-inquiry{display:none;}.nav-toggle{display:flex;}}

/* 线性图标（配合 assets/icons.svg；随文字色，选中/悬停自动转红） */
.ico{display:inline-block;width:1.15em;height:1.15em;vertical-align:-0.16em;color:inherit;flex-shrink:0;}
.dd-ico .ico{width:18px;height:18px;vertical-align:-0.22em;}
.app-icon .ico{width:22px;height:22px;vertical-align:middle;}