:root{--sidebar-width:240px;--sidebar-bg:var(--card-bg);--sidebar-hover:rgba(108,92,231,0.10);--sidebar-active:rgba(108,92,231,0.16);--nav-text:var(--text-secondary);--nav-text-active:var(--text);--nav-icon:#1a1a1a;--nav-icon-active:var(--accent);--divider:var(--border);--scrollbar-thumb:#d0d5dd}[data-theme="dark"]{--sidebar-bg:var(--card-bg);--sidebar-hover:rgba(167,139,250,0.14);--sidebar-active:rgba(167,139,250,0.22);--nav-text:var(--text-secondary);--nav-text-active:var(--text);--nav-icon:#7a7a9a;--nav-icon-active:var(--accent);--divider:var(--border);--scrollbar-thumb:#3a3e48}.sidebar{position:fixed;top:0;left:0;width:var(--sidebar-width);height:100vh;height:100dvh;background:var(--sidebar-bg);backdrop-filter:blur(var(--glass-blur));-webkit-backdrop-filter:blur(var(--glass-blur));border-right:1px solid var(--border);display:flex;flex-direction:column;z-index:100;transition:transform 0.4s cubic-bezier(0.22, 1, 0.36, 1),background 0.35s ease,width 0.35s cubic-bezier(0.22, 1, 0.36, 1);will-change:transform;overflow:hidden;box-shadow:2px 0 20px rgba(0, 0, 0, 0.08)}
.sidebar::before{content:"";position:absolute;inset:0;background:radial-gradient(circle at 50% 0%, var(--accent), transparent 50%);opacity:.14;pointer-events:none;z-index:0}
.sidebar-header,.sidebar-nav,.sidebar-footer{position:relative;z-index:1}.sidebar-header{padding:20px 18px 18px;display:flex;align-items:center;gap:12px;flex-shrink:0}.sidebar-nav{flex:1;overflow-y:auto;overflow-x:hidden;padding:6px 12px;display:flex;flex-direction:column;gap:2px;scroll-behavior:smooth;min-height:0;-webkit-overflow-scrolling:touch;overscroll-behavior:contain;scrollbar-width:none;-ms-overflow-style:none}.sidebar-nav::-webkit-scrollbar{display:none}.sidebar-nav::-webkit-scrollbar-thumb{background:var(--scrollbar-thumb);border-radius:4px}.sidebar-nav::-webkit-scrollbar-track{background:var(--scrollbar-track)}.nav-section-label{font-size:0.68rem;text-transform:uppercase;letter-spacing:1.5px;color:var(--nav-text);padding:16px 8px 6px;font-weight:600;opacity:0.5;white-space:nowrap;transition:opacity 0.3s ease;flex-shrink:0}.nav-item{display:flex;align-items:center;gap:12px;padding:10px 13px;border-radius:9px;cursor:pointer;color:var(--nav-text);font-size:0.9rem;font-weight:500;transition:all 0.2s ease;position:relative;white-space:nowrap;text-decoration:none;user-select:none;-webkit-tap-highlight-color:transparent;overflow:hidden;width:215px;height:43px;flex-shrink:0;box-sizing:border-box}.nav-item:hover{background:var(--sidebar-hover);color:var(--nav-text-active)}.nav-item:active{transform:scale(0.97)}.nav-item.active{background:var(--sidebar-active);color:var(--nav-text-active);font-weight:600;box-shadow:inset 3px 0 0 var(--accent);border-radius:10px 10px 10px 10px}.nav-item .nav-icon{width:20px;text-align:center;font-size:1.1rem;flex-shrink:0;transition:color 0.2s ease,transform 0.2s ease;color:var(--nav-icon)}.nav-item.active .nav-icon{color:var(--nav-icon-active);transform:scale(1.1)}.nav-item:hover .nav-icon{color:var(--nav-icon-active)}.nav-item:not(.active) .nav-badge{background:transparent;color:var(--nav-text);font-weight:400}.sidebar-footer{padding:12px;flex-shrink:0;border-top:1px solid var(--divider)}.sidebar-footer .nav-item{font-size:0.82rem;padding:9px 12px;border-radius:8px;width:auto;height:auto}.sb-animating .sidebar{backdrop-filter:none!important;-webkit-backdrop-filter:none!important}.sidebar-overlay{position:fixed;inset:0;background:rgba(0, 0, 0, 0.5);z-index:99;opacity:0;pointer-events:none;transition:opacity 0.35s ease;backdrop-filter:blur(2px);-webkit-backdrop-filter:blur(2px)}
@media (min-width: 901px){body.sidebar-collapsed .sidebar{transform:translateX(-100%)}}.sidebar-overlay.visible{opacity:1;pointer-events:auto}@media (max-width: 900px){.sidebar{transform:translateX(-100%);width:260px}.sidebar.open{transform:translateX(0)}}/* ---- 私密分类：侧边栏/标签锁标记 ---- */.nav-lock{margin-left:2px;font-size:0.8rem;opacity:0.85}
/* ---- 返回顶部透明按钮（公共组件：首页/search 页共用） ---- */
.back-to-top{position:fixed;right:22px;bottom:22px;z-index:200;width:48px;height:48px;border-radius:50%;display:flex;align-items:center;justify-content:center;cursor:pointer;color:var(--text);background:rgba(140,140,160,0.12);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border:1px solid rgba(255,255,255,0.18);box-shadow:0 6px 20px rgba(0,0,0,0.18);opacity:0;visibility:hidden;transform:translateY(14px);transition:opacity 0.3s ease,transform 0.3s ease,visibility 0.3s ease,background 0.2s ease}
.back-to-top:hover{background:var(--accent);color:#fff;border-color:transparent;box-shadow:0 8px 26px var(--accent-glow)}
.back-to-top.visible{opacity:1;visibility:visible;transform:translateY(0)}
.back-to-top svg{display:block}
@media (max-width:900px){.back-to-top{right:16px;bottom:16px;width:44px;height:44px}}
/* ---- SVG 图标尺寸（图标管理 / 分类图标，前台与后台共用） ----
   仅定尺寸，不强制 fill/stroke：SVG 自带的 fill="none" stroke="currentColor" 保持原语义，
   currentColor 通过 .nav-icon 的 color 自动跟随双主题，避免 lucide 描边图标被填成实心。 */
.nav-icon svg{width:1.15em;height:1.15em;display:block;overflow:visible}
.nf-group-title .nav-icon svg{width:1.2em;height:1.2em;display:inline-block;vertical-align:-0.2em;overflow:visible}