/* 右下角悬浮按钮：回到顶部 / 回到首页 */
.fb-wrap{position:fixed;right:18px;bottom:26px;z-index:9999;display:flex;flex-direction:column;gap:12px}
.fb-btn{display:flex;align-items:center;justify-content:center;width:46px;height:46px;border-radius:50%;background:rgba(240,130,0,.94);color:#fff;font-size:20px;text-decoration:none;box-shadow:0 4px 14px rgba(240,130,0,.35);transition:transform .25s,box-shadow .25s,background .25s;-webkit-tap-highlight-color:transparent}
.fb-btn:hover{transform:translateY(-3px);background:#d96a00;box-shadow:0 8px 20px rgba(240,130,0,.45);color:#fff}
.fb-btn:active{transform:translateY(0)}
.fb-btn .fb-tip{position:absolute;right:58px;white-space:nowrap;font-size:12px;color:#fff;background:rgba(43,43,43,.88);padding:5px 10px;border-radius:6px;opacity:0;pointer-events:none;transition:opacity .2s}
.fb-btn:hover .fb-tip{opacity:1}
.fb-btn.fb-top{font-size:18px}
.fb-btn.fb-top::before{content:"↑";line-height:1}
.fb-btn.fb-home::before{content:"🏠";line-height:1}
.fb-hidden{display:none}
@media(max-width:640px){.fb-wrap{right:14px;bottom:20px}.fb-btn{width:42px;height:42px;font-size:18px}}