/* 大象民宿 · 首页导航层
   顶部导航条 + MENU 按钮 + 全屏菜单 */

/* ═══════════════════════════════════
   顶部导航
   ═══════════════════════════════════ */
.topbar{
  position:fixed;top:max(env(safe-area-inset-top,0px) - 16px, 10px);left:0;right:0;z-index:100;
  display:flex;align-items:center;justify-content:center;
  padding:12px clamp(16px,4vw,32px);
  color:#fff;background:transparent;
  pointer-events:none;
  transition:padding .25s ease;
}
.topbar .brand{pointer-events:auto}
.topbar .brand{
  display:flex;flex-direction:column;align-items:center;gap:2px;
  text-decoration:none;color:#fff;line-height:1.05;
  transform-origin:center top;
}
.topbar .brand-word{
  display:block;width:clamp(280px,85vw,760px);height:auto;
  mix-blend-mode:difference;
}
.topbar .brand-sub{
  font-family:'Space Mono','PingFang SC',monospace;
  font-size:10.5px;color:rgba(255,255,255,.78);
  letter-spacing:.18em;
  transition:opacity .25s ease,transform .25s ease;
  mix-blend-mode:difference;
}
.topbar.is-solid .brand-sub{opacity:0;transform:translateY(-3px)}
@media(max-width:640px){
  .topbar{padding:10px 16px}
}

/* ══ MENU 按钮（固定定位，独立于导航条）══ */
.menu-btn{
  position:fixed;top:calc(max(env(safe-area-inset-top,0px) - 16px, 10px) + 8px);right:14px;z-index:160;
  width:44px;height:44px;padding:0;border:0;
  background:none;cursor:pointer;
}
.menu-btn .menu-btn-bg{
  position:absolute;inset:0;background:#25292b;
  border-radius:50%;transition:transform .3s ease;z-index:1;
}
.menu-btn:hover .menu-btn-bg{transform:scale(1.08)}
.menu-btn .menu-btn-label{
  position:relative;z-index:2;display:block;
  font-family:'Space Mono','PingFang SC',monospace;
  font-size:9px;font-weight:500;letter-spacing:.14em;
  color:#fff;text-align:center;line-height:44px;text-transform:uppercase;
}

/* ═══════════════════════════════════
   全屏菜单
   ═══════════════════════════════════ */
.site-nav{display:none;position:fixed;inset:0;z-index:150}
.site-nav.open{display:block}
.site-nav .nav-overlay{position:absolute;inset:0;background:rgba(0,0,0,.45);cursor:pointer;z-index:1}
.site-nav .nav-panel{
  position:absolute;top:0;right:0;width:50%;height:100vh;
  background:#25292b;z-index:2;overflow-y:auto;padding:120px 40px 200px;
}
/* 移动端：底部抽屉（bottom sheet），上方留半透明遮罩，点空白可关闭 */
@media(max-width:640px){
  .site-nav .nav-overlay{background:rgba(0,0,0,.5);animation:navFade .25s ease both}
  .site-nav .nav-panel{
    top:auto;bottom:0;left:0;right:0;width:100%;height:auto;max-height:85vh;
    padding:22px 24px calc(30px + env(safe-area-inset-bottom,0px));
    background:rgba(37,41,43,.92);
    -webkit-backdrop-filter:blur(16px) saturate(140%);
    backdrop-filter:blur(16px) saturate(140%);
    border-radius:22px 22px 0 0;
    box-shadow:0 -10px 50px rgba(0,0,0,.42);
    overflow-y:auto;
    animation:sheetUp .34s cubic-bezier(.22,.61,.36,1) both;
  }
  .site-nav .nav-panel::before{
    content:"";display:block;width:42px;height:4px;border-radius:2px;
    background:rgba(255,255,255,.26);margin:0 auto 18px;
  }
}
@keyframes sheetUp{from{transform:translateY(100%)}to{transform:translateY(0)}}
@keyframes navFade{from{opacity:0}to{opacity:1}}
.site-nav .nav-main{list-style:none;margin-bottom:60px}
.site-nav .nav-main li{margin-bottom:8px}
.site-nav .nav-main a{
  font-family:'Playfair Display',serif;font-weight:300;
  font-size:clamp(2rem,5vw,4.5rem);line-height:1.1;
  color:rgba(255,255,255,.92);transition:opacity .2s;display:inline-block;
}
.site-nav .nav-main a:hover{opacity:.6}
.site-nav .nav-sec{list-style:none;padding:0;border-top:1px solid rgba(255,255,255,.15);padding-top:20px}
.site-nav .nav-sec li{display:inline-block;margin-right:20px}
.site-nav .nav-sec a{
  font-family:'Space Mono',monospace;font-size:clamp(.75rem,1.2vw,1rem);
  text-transform:uppercase;color:rgba(255,255,255,.6);letter-spacing:.08em;transition:color .2s
}
.site-nav .nav-sec a:hover{color:#fff}