/* 01 · 闭合封面采用与展开书同色的布纹和银杏画稿；右半本围绕左侧书脊打开。 */
.album-stage{position:relative}
/* 尚未开始的纸页保持隐藏，延迟结束后才接力翻转；不截获点击。 */
.album-riffle{visibility:hidden;pointer-events:none}
.album-cover{position:absolute;left:50%;top:6%;width:44%;height:78%;border:0;padding:0;background:none;transform-origin:left center;transform-style:preserve-3d;z-index:15;cursor:pointer;color:#fff4d3;text-align:center;box-shadow:none}
.album-cover:before{content:'';position:absolute;inset:5px -6px -6px 5px;background:repeating-linear-gradient(0deg,#e9dfcb 0 2px,#f7f0df 2px 4px);border:1px solid #c8bca2;border-radius:5px;pointer-events:none}
.album-cover-front,.album-cover-back{position:absolute;inset:0;backface-visibility:hidden;border-radius:5px 10px 10px 5px;box-shadow:2px 5px 13px #55708322}
.album-cover-front{display:flex;flex-direction:column;align-items:center;padding:0;color:inherit;text-align:center;cursor:pointer;background:repeating-linear-gradient(0deg,#dce5e511 0 1px,transparent 1px 3px),repeating-linear-gradient(90deg,#4b728811 0 1px,transparent 1px 3px),linear-gradient(110deg,#65899e,#97b0be 38%,#83a3b5);border:1px solid #638497;overflow:hidden}
.album-cover-front:before{content:'';position:absolute;inset:14px 14px 14px 21px;border:1px solid #ead5a27a;border-radius:2px;pointer-events:none}
.album-cover-front:after{content:'';position:absolute;left:8px;top:0;bottom:0;width:7px;border-left:1px solid #d4ded34d;background:#52768a18}
.album-cover-front>small{margin-top:9%;font-size:clamp(9px,.9cqw,12px);letter-spacing:2px;color:#f4e4c1}
.album-cover-front>strong{font-size:clamp(25px,3cqw,36px);font-weight:400;letter-spacing:5px;margin-top:7%}
.album-cover-art{display:block;width:65%;height:45%;margin:auto 0}
.album-cover-art .art{background:none!important;width:100%;height:100%}
.album-cover-art .study-art{opacity:.95}
.album-cover-prompt{margin-bottom:9%;font-size:clamp(11px,1.1cqw,14px);letter-spacing:1px;color:#f7edda}
.album-cover-back{background:linear-gradient(90deg,#f4ecdc,#fffaf0 12%,#f8f1e4);transform:rotateY(180deg);border:1px solid #d4c3a34f}
.album-cover-back>.album-photo-content{position:absolute;left:9.0909%;top:8.9744%;width:81.8182%;height:83.3333%}
.album-cover-back .album-work{cursor:inherit}
.album-cover:has(.album-cover-front:focus-visible){outline:2px dashed #7c96a5;outline-offset:8px}
.album-closed-hint{font-size:12px;color:#9b9e92;text-align:center;letter-spacing:1px;margin:-38px 0 24px;position:relative}
.album-close{position:absolute;right:8%;top:0;z-index:25;border:1px solid #c9b78e77;border-radius:18px;background:#fff9ec;color:#8d7a52;padding:8px 13px;font-size:12px}
.album-close span{margin-left:6px;color:#a69a80}
.album-close:hover{background:#f4e9ce}
.album-close:focus-visible{outline:2px dashed #7c96a5;outline-offset:3px}
.album-close:disabled{opacity:.5;cursor:default}
/* 02 · 只有open状态可以翻页；过渡中内容可见但inert，闭合时只露出封面。 */
.album-page[data-book-state="closed"] .album-book{transform:translateX(-22%)}
.album-page[data-book-state="closed"] :is(.album-book-clip,.album-left,.album-right,.album-bookmark-holder){opacity:0;visibility:hidden}
/* 底页留在封面下面，开合不再整本淡入淡出；左侧纸叠沿翻转进度显露。 */
.album-book-clip{clip-path:inset(0% 0% 0% 0%)}
.album-page[data-book-state="closed"] .album-book-clip{opacity:1;visibility:visible;clip-path:inset(0% 0% 0% 49.5%)}
.album-page[data-book-state="closed"] .album-right{opacity:1}
.album-page[data-book-state="open"] .album-cover{visibility:hidden;transform:rotateY(-180deg)}
.album-open-tools[hidden],.album-close[hidden],.album-closed-hint[hidden]{display:none}
.album-page-zone{position:absolute;top:6%;width:44%;height:78%;z-index:1;border:0;padding:0;background:none;color:#b1a283;cursor:pointer}
.zone-prev{left:6%}.zone-next{left:50%}
.album-page-zone:after{position:absolute;bottom:5%;font-size:18px;opacity:0;transition:opacity .2s;pointer-events:none}
.zone-prev:after{content:'←';left:6%}.zone-next:after{content:'→';right:6%}
.album-page-zone:not(:disabled):hover:after{opacity:.6}
.album-page-zone:disabled{cursor:default}
.album-page:not([data-book-state="open"]) .album-page-zone{visibility:hidden}
.album-page[data-book-state="open"] .album-left,.album-page[data-book-state="open"] .album-right{cursor:pointer}
@media(max-width:700px){
 .album-cover{left:10%;width:86%;transform-origin:left center}
 .album-page[data-book-state="closed"] .album-book{transform:none}
 .album-page[data-book-state="closed"] .album-book-clip{clip-path:inset(0% 0% 0% 0%)}
 /* 单页册的封面收至书脊处，合上时从同一姿态返回。 */
 .album-page[data-book-state="open"] .album-cover{transform:rotateY(-82deg);opacity:0}
 .album-cover-back{display:none}
 .album-cover-front>small{font-size:9px;letter-spacing:1px}
 .album-cover-front>strong{font-size:26px;letter-spacing:3px}
 .album-cover-prompt{font-size:11px}
 .album-close{right:0;top:-12px;font-size:11px;padding:7px 10px}
 .album-closed-hint{font-size:10px;letter-spacing:0;margin-top:-25px}
 .zone-prev{left:10%;width:38%}.zone-next{left:48%;width:48%}
}