:root { color-scheme: light; font-family: 'Malgun Gothic', 'Apple SD Gothic Neo', sans-serif; color: #203b36; background: #f2f3eb; font-size: 17px; }
* { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; }
.top { min-height: 72px; padding: 0 max(24px,5vw); display: flex; align-items: center; justify-content: space-between; gap: 1rem; background: #fffefa; border-bottom: 1px solid #d3dfd7; font-weight: 700; }
.top a { min-height: 48px; display: flex; align-items: center; color: #25584a; }
main { width: min(1120px,100%); margin: auto; padding: 48px 26px 70px; }
h1,h2,h3,p { margin-top: 0; }
h1 { font-size: clamp(2rem,4vw,3rem); line-height: 1.2; }
h2 { font-size: 1.4rem; }
p { line-height: 1.65; }
.eyebrow { color: #794823; font-weight: 700; }
.lead { font-size: 1.2rem; font-weight: 700; line-height: 1.6; }
.intro { min-height: 510px; display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; align-items: center; }
.intro-art { width: 100%; max-width: 450px; justify-self: center; }
fieldset { border: 0; padding: 0; margin: 1.5rem 0; }
legend { font-weight: 700; margin-bottom: .6rem; }
label { display: block; margin: .5rem 0; line-height: 1.5; }
input[type='radio'] { width: 20px; height: 20px; vertical-align: middle; accent-color: #315b50; }
button,summary { font: inherit; }
button { min-height: 48px; padding: .7rem 1rem; border: 2px solid #496c60; border-radius: .55rem; color: #21483e; background: #fffefa; font-weight: 700; cursor: pointer; }
button.primary { color: #fff; background: #315a50; border-color: #315a50; }
button:disabled { opacity: .55; cursor: default; }
button[aria-pressed='true'] { border: 4px solid #90501f; background: #fff0d9; }
button:focus-visible,summary:focus-visible,input:focus-visible,a:focus-visible { outline: 3px solid #9a4c23; outline-offset: 3px; }
.heading { display: flex; align-items: start; justify-content: space-between; gap: 1rem; }
details { margin-bottom: 1rem; padding: .7rem 1rem; background: #e1ece5; border-radius: .7rem; }
summary { min-height: 44px; padding: .55rem 0; font-weight: 700; cursor: pointer; }
.workspace { display: grid; grid-template-columns: 1.2fr 1fr; gap: 1rem; align-items: start; }
.panel { padding: 1.4rem; border: 1px solid #cddcd3; background: #fffefa; border-radius: 1rem; }
.diagram { background: #edf4ee; border-radius: .7rem; }
.diagram svg { display: block; width: 100%; }
.tracks { fill: none; stroke: #9fb5a7; stroke-width: 16; stroke-linecap: round; stroke-linejoin: round; }
.junction,.empty { fill: #fffefa; stroke: #315e51; stroke-width: 3; }
.full { fill: #315e51; stroke: #315e51; stroke-width: 3; }
.diagram text { text-anchor: middle; font-size: 17px; font-weight: 700; fill: #203b36; }
.diagram .full-text { fill: #fff; }
.valve-mark { fill: none; stroke: #a24e20; stroke-width: 5; stroke-linecap: round; }
.marble { fill: #d58343; stroke: #633b24; stroke-width: 3; }
.position { margin-top: .8rem; font-weight: 700; }
.preview { padding: .7rem; border-radius: .5rem; background: #edf3e9; }
.choices,.actions { display: flex; flex-wrap: wrap; gap: .5rem; }
.status { margin: 1rem 0; padding: .8rem 1rem; background: #e2ede1; border-radius: .6rem; min-height: 3rem; }
.result { max-width: 720px; margin: 2rem auto; }
.result button { margin: .3rem; }
footer { border-top: 1px solid #cddcd3; padding: 1.5rem max(24px,5vw); color: #455b50; font-size: .9rem; }
dialog { max-width: min(90vw, 480px); border: 2px solid #396158; border-radius: 16px; padding: 24px; color: #243b36; } dialog::backdrop { background: #182c27b3; }
@media (max-width: 760px) { main { padding: 32px 16px 48px; } .intro,.workspace { grid-template-columns: 1fr; } .intro { gap: 1rem; } .intro-art { max-width: 320px; } .heading { flex-wrap: wrap; } .panel { padding: 1rem; } }
@media (prefers-reduced-motion: reduce) { *,*::before,*::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; } }

/* 판 선택 화면 목록 링크 */
#hub-link, #hub { color: #174f74; display: inline-flex; align-items: center; min-height: 44px; padding: 0 4px; font-weight: 700; }
#hub-link[hidden], #hub[hidden] { display: none; }