/* Lux 布局：毛玻璃导航 / 页脚 / 悬浮按钮 / 响应式 */

/* 顶部毛玻璃悬浮导航 */
.nav{position:sticky;top:0;z-index:100;background:var(--nav-bg);
  -webkit-backdrop-filter:saturate(160%) blur(14px);backdrop-filter:saturate(160%) blur(14px);
  border-bottom:.5px solid var(--border)}
.nav-inner{display:flex;align-items:center;gap:24px;height:var(--nav-h)}
.brand{display:flex;align-items:center;gap:10px;font-weight:500;font-size:17px;color:var(--text);letter-spacing:.3px}
.brand:hover{color:var(--text)}
.brand-mark{display:inline-flex;align-items:center;justify-content:center;width:30px;height:30px;
  border:1px solid var(--accent);color:var(--accent);border-radius:8px;font-family:var(--font-mono);font-size:12px}
.nav-menu{list-style:none;display:flex;align-items:center;gap:22px;margin:0;padding:0;flex:1}
.nav-menu li{list-style:none}
.nav-menu a{font-size:14px;color:var(--text-muted)}
.nav-menu a:hover{color:var(--text)}
.theme-toggle{width:38px;height:38px;border-radius:var(--radius-ctl);
  border:.5px solid var(--border-strong);background:transparent;color:var(--accent);cursor:pointer;
  display:inline-flex;align-items:center;justify-content:center;font-size:16px;transition:border-color .2s}
.theme-toggle:hover{border-color:var(--accent)}
.theme-toggle .ic-sun{display:none}
:root[data-theme="light"] .theme-toggle .ic-sun{display:inline}
:root[data-theme="light"] .theme-toggle .ic-moon{display:none}
.nav-toggle{display:none}

/* 页脚 */
.site-footer{margin-top:80px;border-top:.5px solid var(--border);padding:32px 0;color:var(--text-dim);font-size:13px;text-align:center}
.site-footer p{margin:0}
.footer-beian{margin-top:6px}
.footer-beian a{color:var(--text-dim)}
.footer-beian a:hover{color:var(--accent)}

/* 悬浮按钮 */
.floating{position:fixed;right:clamp(16px,3vw,32px);bottom:clamp(16px,3vw,32px);z-index:90;display:flex;flex-direction:column;gap:10px}
.fab{width:44px;height:44px;border-radius:50%;border:.5px solid var(--border-strong);
  background:var(--surface);color:var(--accent);cursor:pointer;font-size:18px;line-height:1;
  display:inline-flex;align-items:center;justify-content:center;box-shadow:var(--shadow);
  opacity:0;visibility:hidden;transform:translateY(8px);transition:opacity .3s ease,transform .25s ease,border-color .2s}
.fab.show{opacity:1;visibility:visible;transform:none}
.fab:hover{transform:translateY(-3px);border-color:var(--accent)}

/* 响应式：移动端导航抽屉 */
@media(max-width:768px){
  .nav-menu{position:fixed;left:0;right:0;top:var(--nav-h);flex-direction:column;align-items:flex-start;
    background:var(--nav-bg);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);
    border-bottom:.5px solid var(--border);padding:18px 24px;gap:16px;flex:none;
    transform:translateY(-130%);opacity:0;pointer-events:none;transition:transform .3s ease,opacity .3s ease}
  .nav-menu.open{transform:translateY(0);opacity:1;pointer-events:auto}
  .nav-toggle{display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;
    border-radius:var(--radius-ctl);border:.5px solid var(--border-strong);background:transparent;color:var(--text);cursor:pointer;font-size:18px}
}