/* === BxB nav === */
#topbar {
  background: var(--bg2); border-bottom: 1px solid var(--border);
  padding: 8px 16px; display: flex; align-items: center; gap: 12px;
  flex-shrink: 0; position: sticky; top: 0; z-index: 100; min-height: 52px;
}
#topbar h1 { font-size: 16px; font-weight: 700; color: var(--accent); white-space: nowrap; margin: 0; }
#page-nav { display: flex; gap: 0; }
.nav-link {
  padding: 5px 18px; font-size: 13px; font-weight: 600; color: var(--text2);
  text-decoration: none; border-bottom: 2px solid transparent; transition: color .15s; white-space: nowrap;
}
/* 触屏 (iPad/手机) 不要 :hover — iOS Safari 在有 :hover 的 <a> 上有 hover-to-activate
   bug：第一次 tap 仅触发 hover 状态（refresh 转圈但不 navigate），第二次 tap 才
   commit 跳转。@media (hover: hover) 让触屏跳过 :hover，原生 click 直接 navigate。 */
@media (hover: hover) {
  .nav-link:hover { color: var(--text); }
}
.nav-link.active { color: var(--accent); border-bottom-color: var(--accent); }
#topbar-right { margin-left: auto; display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
#nav-hamburger {
  display: none; background: none; border: none; color: var(--text);
  font-size: 22px; cursor: pointer; padding: 2px 6px; line-height: 1; border-radius: 4px;
}
#nav-hamburger:hover { background: var(--bg3); }
#revise-bar { display: none; align-items: center; gap: 8px; }
#revise-status { font-size: 12px; color: #55bb55; }
.btn-revise-save {
  background: #1e5c1e; color: #aaffaa; border: 1px solid #2d8c2d;
  border-radius: 6px; padding: 4px 12px; font-size: 12px; cursor: pointer; font-weight: 600;
}
.btn-revise-save:hover { background: #266626; }
.btn-revise-save:disabled { opacity: .5; cursor: default; }
#save-toast {
  display: none; align-items: center; gap: 6px;
  padding: 5px 12px; border-radius: 6px;
  background: rgba(80,200,120,.12); border: 1px solid rgba(80,200,120,.4);
  color: #7dd99f; font-size: 12px; font-weight: 600; white-space: nowrap;
  animation: save-toast-in .25s ease-out;
}
#save-toast.show { display: flex; }
#save-toast a { color: var(--accent); text-decoration: none; }
#save-toast a:hover { text-decoration: underline; }
@keyframes save-toast-in {
  from { opacity: 0; transform: translateX(8px); }
  to   { opacity: 1; transform: translateX(0); }
}
@media (max-width: 600px) {
  #nav-hamburger { display: block; }
  #page-nav {
    display: none; position: absolute; top: 52px; left: 0; right: 0;
    flex-direction: column; background: var(--bg2);
    border-bottom: 2px solid var(--border);
    box-shadow: 0 6px 16px rgba(0,0,0,.5); z-index: 99;
  }
  #page-nav.open { display: flex; }
  .nav-link { padding: 12px 20px; border-bottom: 1px solid var(--border); border-right: none; white-space: normal; }
  .nav-link.active { border-bottom-color: var(--border); border-left: 3px solid var(--accent); padding-left: 17px; }
}