/* ============================================================
   nav.css — 全站导航/下拉菜单的唯一样式来源
   来源：以表现正常的 index.html 内联版为基准移植（Apple 风格、light-only）
   说明：所有前端页面（中文站 / en 站 / 博客）统一 <link> 本文件，
        页面内联 <style> 中不得再重复定义这些导航选择器。
   ============================================================ */

/* —— 顶栏容器 —— */
.navbar{position:sticky;top:0;z-index:100;background:rgba(255,255,255,0.72);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border-bottom:0.5px solid rgba(0,0,0,0.1)}
.nav-inner{max-width:960px;margin:0 auto;padding:0 1.5rem;display:flex;align-items:center;justify-content:space-between;height:52px}
.logo{font-size:1.05rem;font-weight:700;color:#1d1d1f;letter-spacing:-0.3px;text-decoration:none}

/* —— 主导航（桌面横排，关键基线：display:flex）—— */
.nav-links{display:flex;gap:1.75rem;list-style:none;margin:0;padding:0;align-items:center;overflow:visible}
.nav-links,.nav-links ul{list-style:none!important}

/* —— 下拉分类（关键基线：position:relative，使子菜单锚定父项）—— */
.dropdown{position:relative;display:inline-block}
.dropbtn{color:#6e6e73;font-size:0.82rem;font-weight:500;padding:0.25rem 0;cursor:default;transition:color .2s;text-decoration:none;display:block;white-space:nowrap}
.dropbtn:hover{color:#1d1d1f}
.dropbtn.active-category{color:#007AFF}

/* —— 下拉子菜单浮层 —— */
.dropdown-content{display:none;position:absolute;top:100%;left:50%;transform:translateX(-50%);background:rgba(255,255,255,0.95);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border-radius:10px;box-shadow:0 4px 16px rgba(0,0,0,0.08),0 0 0 0.5px rgba(0,0,0,0.06);padding:.35rem 0;min-width:155px;z-index:200}
.dropdown:hover .dropdown-content{display:block}
.dropdown-content a{display:block;padding:.5rem 1rem;font-size:.82rem;color:#6e6e73;white-space:nowrap;text-decoration:none;transition:background .15s,color .15s}
.dropdown-content a:hover{background:rgba(0,0,0,0.03);color:#1d1d1f}
.dropdown-content a.active{color:#007AFF;font-weight:600}

/* —— 语言切换入口 —— */
.nav-lang a{color:#007AFF!important}
.nav-lang a:hover{color:#0063cc!important}

/* —— 移动端汉堡菜单 —— */
.mob-toggle-input{display:none}
.mob-toggle{display:none;cursor:pointer;font-size:1.4rem;color:#1d1d1f;padding:.25rem;user-select:none}

@media(max-width:767px){
  .mob-toggle{display:block}
  .nav-inner{padding:0 1rem}
  .nav-links{display:none;position:absolute;top:52px;left:0;right:0;background:rgba(255,255,255,0.98);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);flex-direction:column;padding:.5rem 1.5rem;box-shadow:0 4px 12px rgba(0,0,0,0.08);gap:0}
  #mob-toggle:checked~.nav-links{display:flex}
  .nav-links li{width:100%}
  .dropdown{display:block;width:100%}
  .dropbtn{width:100%;padding:.6rem 0}
  .dropdown-content{position:static;transform:none;box-shadow:none;border-radius:0;padding-left:.75rem;background:transparent;backdrop-filter:none;-webkit-backdrop-filter:none;display:none}
  .dropdown:hover .dropdown-content{display:none}
  .dropdown:focus-within .dropdown-content{display:block}
  .nav-lang{border-top:.5px solid rgba(0,0,0,0.06);padding-top:.5rem;margin-top:.25rem;width:100%}
}