:root{color:#111;background:#fff;font-family:Arial,"Helvetica Neue","Hiragino Kaku Gothic ProN",sans-serif}
*{box-sizing:border-box}
html,body{margin:0}
body{min-height:100vh}
header{display:flex;align-items:center;justify-content:space-between;padding:22px clamp(18px,3.2vw,52px)}
a{color:inherit;text-decoration:none}
.logo img{display:block;width:108px;height:auto}
.close{font-size:.7rem;font-weight:700;letter-spacing:.04em}
main{padding:0 clamp(18px,3.2vw,52px) 46px}
.viewer{max-width:1520px;margin:0 auto}
.stage{position:relative;display:flex;align-items:center;justify-content:center;width:100%;height:min(72vh,900px);min-height:420px;background:#f4f4f4;overflow:hidden}
.stage>img{width:100%;height:100%;object-fit:contain}
.arrow{position:absolute;z-index:2;top:50%;width:56px;height:86px;padding:0;border:0;background:transparent;color:#fff;font-family:Arial,sans-serif;font-size:5rem;font-weight:200;line-height:1;transform:translateY(-50%);cursor:pointer;text-shadow:0 1px 12px rgba(0,0,0,.32)}
.arrow:hover{opacity:.7}
.prev{left:2.2%}
.next{right:2.2%}
.thumbs{display:flex;gap:clamp(10px,2.2vw,36px);margin-top:36px;padding:0 0 12px;overflow-x:auto;scrollbar-width:thin;scroll-snap-type:x proximity}
.thumb{flex:0 0 clamp(150px,15.8vw,240px);height:clamp(96px,15vw,240px);padding:0;border:0;background:#eee;cursor:pointer;opacity:.58;scroll-snap-align:start;transition:opacity .2s}
.thumb img{display:block;width:100%;height:100%;object-fit:cover}
.thumb.active,.thumb:hover,.thumb:focus-visible{opacity:1}
.thumb.active{outline:2px solid #111;outline-offset:3px}
h1{max-width:1520px;margin:42px auto 0;color:#777;text-align:center;font-size:clamp(.95rem,1.45vw,1.35rem);font-weight:400;letter-spacing:.02em}
@media(max-width:700px){
  header{padding:18px}
  .logo img{width:92px}
  main{padding:0 0 30px}
  .stage{height:65vh;min-height:360px}
  .arrow{width:42px;height:70px;font-size:4rem}
  .prev{left:8px}
  .next{right:8px}
  .thumbs{gap:10px;margin-top:14px;padding:0 18px 10px}
  .thumb{flex-basis:112px;height:84px}
  h1{margin:25px 18px 0;font-size:.9rem}
}