Visual regression testing

<div class="stage"><div class="title">VISUAL REGRESSION</div><div class="canvas"><div class="compare"><div class="screen base"><div class="nav"></div><div class="card"></div><div class="card"></div></div><div class="screen current"><div class="nav"></div><div class="card shifted"></div><div class="card"></div></div><div class="wipe"></div></div><div class="caption">baseline <span>← compare →</span> current</div></div></div>

.stage{width:min(94vw,820px);height:min(88vh,330px);box-sizing:border-box;padding:clamp(9px,2.4vmin,18px);border:1px solid var(--line);border-radius:13px;background:var(--surface);display:flex;flex-direction:column;gap:clamp(7px,2vmin,14px);font:600 clamp(12px,2.5vmin,16px)/1.28 "Pretendard Variable",Pretendard,-apple-system,BlinkMacSystemFont,"Apple SD Gothic Neo",sans-serif;color:var(--fg);overflow:hidden}.title{color:var(--accent);letter-spacing:.035em;flex:none}.canvas{position:relative;flex:1;min-height:0;display:flex;align-items:center;justify-content:center}.muted{color:var(--muted)}.mono{font-family:ui-monospace,SFMono-Regular,monospace}.box{border:1px solid var(--line);border-radius:8px;background:var(--bg);padding:clamp(5px,1.4vmin,12px);text-align:center}.active{border-color:var(--accent)!important;color:var(--accent)!important;background:color-mix(in srgb,var(--accent) 12%,var(--surface))!important}.canvas{flex-direction:column;gap:clamp(7px,2vmin,12px)}.compare{position:relative;width:min(90%,400px);height:70%;min-height:95px;border:1px solid var(--line);border-radius:6px;overflow:hidden}.screen{position:absolute;inset:0;padding:9px;background:var(--bg)}.screen.current{clip-path:inset(0 0 0 50%);animation:reveal 3s ease-in-out infinite alternate}.nav{height:18%;background:var(--line);border-radius:3px;margin-bottom:8px}.card{width:72%;height:18%;border:2px solid var(--accent);border-radius:4px;margin:6px 0}.shifted{transform:translateX(10px);border-color:var(--accent-3)}.wipe{position:absolute;top:0;bottom:0;left:50%;width:2px;background:var(--accent);animation:slide 3s ease-in-out infinite alternate}@keyframes reveal{to{clip-path:inset(0 0 0 16%)}}@keyframes slide{to{left:16%}}.caption{display:flex;gap:8px;justify-content:space-between;width:min(90%,400px)}.caption span{color:var(--accent)}