.chsel{display:flex;flex-wrap:wrap;gap:8px;margin:16px 0 20px;}.chsel-btn{background:#1a1a1a;border:1px solid #3a3a3a;color:#bbb;padding:9px 15px;border-radius:6px;cursor:pointer;font-size:.82em;letter-spacing:.6px;font-family:inherit;transition:.15s;}.chsel-btn:hover{border-color:#8b0000;color:#fff;background:#221414;}.chsel-btn.active{background:#8b0000;border-color:#c41e3a;color:#fff;font-weight:700;}.chapter-page{display:none;}.chapter-page.active{display:block;animation:chfade .18s ease-in;}@keyframes chfade{from{opacity:0;}to{opacity:1;}}.chapter-head{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin:0 0 16px;padding:12px 14px;background:linear-gradient(90deg,#2a0d0d,#160808);border-left:4px solid #c41e3a;border-radius:6px;}.chapter-head .ch-h-title{font-family:Georgia,serif;font-size:1.25em;font-weight:700;color:#fff;}.chapter-head .ch-h-region{color:#9a8f8f;font-size:.86em;font-style:italic;}.ch-pager{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-top:22px;padding-top:16px;border-top:1px solid #2a2a2a;}.ch-pager .cnt{color:#8a8a8a;font-size:.84em;letter-spacing:1px;white-space:nowrap;}@media(max-width:640px){.chsel-btn{flex:1 1 44%;padding:9px 8px;font-size:.76em;}.ch-pager{flex-wrap:wrap;justify-content:center;}.ch-pager .cnt{order:-1;width:100%;text-align:center;}}
/* sticky chapter selector */
.chsel{position:sticky;top:var(--chsel-top,148px);z-index:90;background:rgba(10,10,10,.96);padding:10px;margin:16px -10px 20px;border-radius:0 0 10px 10px;box-shadow:0 8px 16px -8px rgba(0,0,0,.85);backdrop-filter:blur(4px);justify-content:center;}
#walktop{scroll-margin-top:var(--chsel-top,148px);}
@media(max-width:640px){.chsel{overflow-x:auto;flex-wrap:nowrap;justify-content:flex-start;-webkit-overflow-scrolling:touch;padding:8px;scrollbar-width:none;}.chsel::-webkit-scrollbar{display:none;}.chsel .chsel-btn{flex:0 0 auto;white-space:nowrap;}}