/* 轻量单图查看器 - 高清版 */
.iv-overlay{position:fixed;top:0;left:0;width:100vw;height:100vh;background:rgba(0,0,0,0.88);z-index:999999;display:flex;align-items:center;justify-content:center;opacity:0;visibility:hidden;transition:opacity .2s ease,visibility .2s ease;touch-action:none;overflow:hidden}
.iv-overlay.iv-open{opacity:1;visibility:visible}
.iv-img{display:block;object-fit:contain;cursor:grab;user-select:none;-webkit-user-drag:none;border-radius:6px;box-shadow:0 10px 30px rgba(0,0,0,0.5);image-rendering:-webkit-optimize-contrast}
.iv-img:active{cursor:grabbing}
.iv-close{position:absolute;top:16px;right:16px;width:38px;height:38px;border-radius:50%;background:rgba(255,255,255,0.2);border:none;color:#fff;font-size:24px;line-height:38px;text-align:center;cursor:pointer;z-index:10;padding:0;outline:none;display:flex;align-items:center;justify-content:center;backdrop-filter:blur(4px);-webkit-backdrop-filter:blur(4px);transition:background .15s ease,transform .15s ease}
.iv-close:active{transform:scale(0.9);background:rgba(255,255,255,0.35)}