:root {
  color-scheme: dark;
  --ink: #090a09;
  --panel: #141715;
  --panel-strong: #1a1d1b;
  --line: rgba(240, 244, 235, 0.16);
  --muted: #a9afa5;
  --lime: #d8f233;
  --warm: #f3f4ed;
  font-family: "Pretendard", "SUIT", "Noto Sans KR", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { background: var(--ink); scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  color: var(--warm);
  background:
    radial-gradient(circle at 76% 7%, rgba(216, 242, 51, 0.12), transparent 25rem),
    linear-gradient(140deg, #0a0b0a 0%, #111311 42%, #080909 100%);
}
button, a { font: inherit; }
a { color: inherit; text-decoration: none; }
button { -webkit-tap-highlight-color: transparent; }

.skip-link {
  position: fixed;
  left: 1rem;
  top: -5rem;
  z-index: 50;
  padding: .7rem .9rem;
  color: #111;
  background: var(--lime);
  border-radius: .5rem;
}
.skip-link:focus { top: 1rem; }

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 1200px;
  min-height: 76px;
  padding: 1.1rem clamp(1.25rem, 4vw, 3rem);
  margin: auto;
  border-bottom: 1px solid var(--line);
}
.brand { display: inline-flex; align-items: baseline; gap: .35rem; letter-spacing: -.045em; white-space: nowrap; }
.brand strong { font-size: clamp(1.15rem, 2.7vw, 1.6rem); }
.brand span { color: var(--lime); font-size: .76rem; font-weight: 800; letter-spacing: .12em; }
nav { display: flex; align-items: center; gap: clamp(.5rem, 2vw, 1.25rem); }
nav a { color: var(--muted); font-size: .78rem; font-weight: 700; white-space: nowrap; }
nav a:hover, nav a:focus-visible { color: var(--lime); }

.flow-shell { width: min(100%, 1200px); margin: auto; padding: clamp(3.5rem, 10vw, 8rem) clamp(1.25rem, 4vw, 3rem) 5rem; }
.hero { max-width: 720px; margin-bottom: clamp(3rem, 8vw, 6rem); }
.eyebrow { margin: 0 0 .8rem; color: var(--lime); font-size: .75rem; font-weight: 900; letter-spacing: .16em; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 1.2rem; font-size: clamp(2.85rem, 8.4vw, 6.5rem); line-height: .94; letter-spacing: -.075em; }
h2 { margin-bottom: 0; font-size: clamp(1.8rem, 4vw, 3.45rem); line-height: 1.02; letter-spacing: -.06em; }
h3 { margin-bottom: .6rem; font-size: clamp(1.35rem, 2.5vw, 1.8rem); letter-spacing: -.045em; }
.lead { max-width: 580px; margin: 0; color: var(--muted); font-size: clamp(1rem, 1.8vw, 1.18rem); line-height: 1.7; }

.flow-options { position: relative; padding: clamp(1.25rem, 4vw, 2.75rem); border: 1px solid var(--line); border-radius: 1.6rem; background: linear-gradient(135deg, rgba(255,255,255,.045), rgba(255,255,255,.012)); box-shadow: 0 32px 100px rgba(0,0,0,.23); }
.section-heading { margin-bottom: 1.35rem; }
.mode-grid { display: grid; gap: .8rem; }
.mode-card, .part-card {
  position: relative;
  width: 100%;
  color: var(--warm);
  text-align: left;
  border: 1px solid var(--line);
  background: rgba(0,0,0,.18);
  cursor: pointer;
  transition: transform .18s ease, border-color .18s ease, background .18s ease, box-shadow .18s ease;
}
.mode-card { display: grid; gap: .8rem; min-height: 216px; padding: 1.3rem; border-radius: 1.1rem; overflow: hidden; }
.mode-card::after { content: ""; position: absolute; inset: auto -16% -45% 35%; aspect-ratio: 1; border-radius: 50%; background: rgba(216,242,51,.08); filter: blur(25px); opacity: 0; transition: opacity .2s ease; }
.mode-card:hover, .mode-card:focus-visible, .mode-card[aria-checked="true"] { border-color: rgba(216,242,51,.75); background: rgba(216,242,51,.065); outline: none; }
.mode-card:hover, .mode-card:focus-visible { transform: translateY(-2px); }
.mode-card[aria-checked="true"] { box-shadow: inset 0 0 0 1px rgba(216,242,51,.16), 0 18px 46px rgba(0,0,0,.23); }
.mode-card[aria-checked="true"]::after { opacity: 1; }
.mode-number, .summary-kicker, .principles article span { color: var(--lime); font-family: ui-monospace, "SFMono-Regular", Menlo, monospace; font-size: .76rem; font-weight: 900; letter-spacing: .12em; }
.mode-title { position: relative; z-index: 1; font-size: 1.45rem; font-weight: 850; letter-spacing: -.045em; }
.mode-copy, .mode-note { position: relative; z-index: 1; color: var(--muted); font-size: .92rem; line-height: 1.55; }
.mode-note { color: #dce1d6; font-size: .78rem; }
.mode-sequence { position: relative; z-index: 1; display: flex; flex-wrap: wrap; gap: .35rem .45rem; color: #dce1d6; font-size: .76rem; font-weight: 750; }
.mode-sequence b { color: var(--lime); }

.part-picker { margin-top: 1rem; padding: 1.25rem; border: 1px solid rgba(216,242,51,.26); border-radius: 1.1rem; background: rgba(216,242,51,.045); }
.part-picker > div:first-child p:last-child { margin-bottom: 1.1rem; color: var(--muted); line-height: 1.55; }
.part-picker strong { color: var(--lime); }
.part-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .65rem; }
.part-card { display: flex; flex-direction: column; min-height: 88px; justify-content: space-between; padding: 1rem; border-radius: .9rem; }
.part-card span { font-size: 1.05rem; font-weight: 800; }
.part-card small { color: var(--muted); font-weight: 700; }
.part-card--available:hover, .part-card--available:focus-visible, .part-card--available[aria-checked="true"] { border-color: var(--lime); outline: none; background: rgba(216,242,51,.11); }
.part-card--available[aria-checked="true"] small { color: var(--lime); }
.part-card:disabled { opacity: .42; cursor: not-allowed; }

.selection-summary { display: grid; gap: .5rem; margin-top: 1.25rem; padding: 1.15rem; border-radius: 1rem; background: #111310; border: 1px solid var(--line); }
.selection-summary strong { font-size: 1.08rem; letter-spacing: -.025em; }
.selection-summary p { margin: 0; color: var(--muted); font-size: .88rem; line-height: 1.55; }
.primary-action { display: flex; width: 100%; align-items: center; justify-content: space-between; gap: 1rem; min-height: 64px; margin-top: .85rem; padding: 1.1rem 1.25rem; color: #10120a; background: var(--lime); border: 1px solid var(--lime); border-radius: .9rem; cursor: pointer; font-weight: 900; font-size: 1.05rem; letter-spacing: -.025em; transition: transform .18s ease, filter .18s ease; }
.primary-action b { font-size: 1.65rem; font-weight: 500; }
.primary-action:hover:not(:disabled), .primary-action:focus-visible:not(:disabled) { outline: none; transform: translateY(-2px); filter: brightness(1.07); }
.primary-action:disabled { cursor: not-allowed; color: #737765; background: #282b26; border-color: #282b26; }
.detail-note { margin: .9rem 0 0; color: #858b80; font-size: .75rem; line-height: 1.55; }

.principles { padding: clamp(4rem, 9vw, 7rem) 0 0; }
.principle-grid { display: grid; gap: 1px; margin-top: 1.7rem; border: 1px solid var(--line); border-radius: 1.2rem; overflow: hidden; background: var(--line); }
.principles article { min-height: 178px; padding: 1.35rem; background: #0e100e; }
.principles article h3 { margin-top: 1.8rem; margin-bottom: .45rem; font-size: 1.12rem; }
.principles article p { margin: 0; color: var(--muted); font-size: .88rem; line-height: 1.55; }

footer { display: flex; flex-wrap: wrap; justify-content: space-between; gap: .75rem; width: min(100%, 1200px); padding: 1.5rem clamp(1.25rem, 4vw, 3rem) 2rem; margin: auto; border-top: 1px solid var(--line); color: #7e847a; font-size: .72rem; letter-spacing: .04em; }

@media (min-width: 640px) {
  .topbar { min-height: 86px; }
  .mode-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .part-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .principle-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

@media (max-width: 480px) {
  .topbar { align-items: flex-start; flex-direction: column; }
  nav { width: 100%; justify-content: space-between; }
  nav a { font-size: .7rem; }
  .flow-shell { padding-top: 3.25rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; }
}
/* Saved-eye-design continuation context */
.source-note {
  margin: 0 0 28px;
  padding: 22px 24px;
  border: 1px solid rgba(216, 242, 51, 0.34);
  border-radius: 22px;
  background:
    radial-gradient(circle at top right, rgba(216, 242, 51, 0.13), transparent 44%),
    rgba(255, 255, 255, 0.035);
}

.source-note h2 {
  margin: 7px 0 8px;
  font-size: clamp(1.2rem, 3vw, 1.55rem);
  letter-spacing: -0.04em;
}

.source-note p:last-child {
  margin: 0;
  max-width: 58ch;
  color: var(--muted, #b8b8b8);
  line-height: 1.65;
}