.checkerboard-bg{background-color:#f8f8f8;background-image:linear-gradient(45deg,#e2e2e2 25%,transparent 25%),linear-gradient(-45deg,#e2e2e2 25%,transparent 25%),linear-gradient(45deg,transparent 75%,#e2e2e2 75%),linear-gradient(-45deg,transparent 75%,#e2e2e2 75%);background-size:16px 16px;background-position:0 0,0 8px,8px -8px,-8px 0}#upload-zone{transition:border-color 0.15s,background-color 0.15s}#upload-zone.dragover{background-color:rgb(30 135 240 / .06);border-color:#1e87f0!important}.preview-panel{position:relative;height:280px;border-radius:6px;overflow:hidden}.preview-panel img{width:100%;height:100%;object-fit:contain;display:none}.preview-panel .panel-placeholder{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;color:#bbb;pointer-events:none}.preview-panel .panel-loading{position:absolute;inset:0;display:none;flex-direction:column;align-items:center;justify-content:center;gap:10px;background:rgb(255 255 255 / .92);backdrop-filter:blur(3px);z-index:10}.tool-btn{display:inline-flex!important;align-items:center;justify-content:center;gap:6px}