:root {
  --bg: #09090b;
  --panel: #111114;
  --surface: #17171b;
  --surface-raised: #1d1d22;
  --border: #29292f;
  --border-strong: #3a3942;
  --text: #f3f1f7;
  --muted: #96939e;
  --quiet: #8a8792;
  --accent: #8878dc;
  --accent-hover: #9b8ce8;
  --success: #94c7ad;
  --danger: #e39797;
  --radius: 18px;
  font-family: Inter, Pretendard, "Noto Sans KR", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
}

* { box-sizing: border-box; }

html { min-width: 320px; background: var(--bg); }
body { margin: 0; min-height: 100vh; background: var(--bg); }
button, input, select { font: inherit; touch-action: manipulation; }
button { cursor: pointer; }

.skip-link {
  position: fixed;
  z-index: 20;
  top: 8px;
  left: 8px;
  padding: 10px 14px;
  color: var(--text);
  background: var(--accent);
  border-radius: 8px;
  transform: translateY(-150%);
}
.skip-link:focus { transform: translateY(0); }

.app-shell { min-height: 100vh; display: grid; grid-template-columns: 340px minmax(0, 1fr); }
.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  padding: 24px 20px 32px;
  border-right: 1px solid var(--border);
  background: var(--panel);
  scrollbar-width: thin;
}
.brand { display: flex; align-items: center; gap: 12px; margin: 0 2px 28px; }
.brand-mark { width: 28px; height: 28px; border: 7px dotted var(--accent); border-radius: 50%; transform: rotate(-18deg); }
h1, h2, h3, p { margin: 0; }
.brand h1 { font-size: 19px; letter-spacing: -0.03em; }
.brand p { margin-top: 3px; color: var(--quiet); font: 500 10px/1.2 ui-monospace, SFMono-Regular, Menlo, monospace; text-transform: uppercase; letter-spacing: 0.12em; }

.source-panel, fieldset {
  margin: 0 0 12px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.section-heading { display: flex; justify-content: space-between; align-items: start; gap: 12px; margin-bottom: 14px; }
.eyebrow, legend span { color: var(--accent); font: 600 10px/1.2 ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: 0.1em; text-transform: uppercase; }
.section-heading h2, legend { font-size: 14px; font-weight: 650; }
.section-heading h2 { margin-top: 5px; }
.text-button { min-height: 44px; padding: 0 4px; border: 0; color: var(--muted); background: transparent; font-size: 12px; }

.drop-zone {
  min-height: 112px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 15px;
  border: 1px dashed var(--border-strong);
  border-radius: 12px;
  color: var(--muted);
  text-align: center;
  cursor: pointer;
  transition: border-color 150ms ease-out, background-color 150ms ease-out;
}
.drop-zone[data-dragging="true"], .drop-zone:focus-within { border-color: var(--accent); background: #201e2a; }
.drop-zone input { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }
.drop-zone strong { color: var(--text); font-size: 13px; }
.drop-zone small { font-size: 11px; }
.upload-icon { color: var(--accent); font-size: 20px; }
.source-name { margin-top: 10px; overflow: hidden; color: var(--quiet); font-size: 11px; text-overflow: ellipsis; white-space: nowrap; }

fieldset { display: grid; gap: 16px; }
legend { width: 100%; padding: 0 0 14px; }
legend span { display: block; margin-bottom: 5px; }
.field { display: grid; gap: 9px; color: var(--muted); font-size: 12px; }
.field > span { display: flex; justify-content: space-between; gap: 10px; }
output { color: var(--text); font-variant-numeric: tabular-nums; }
select {
  width: 100%;
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  color: var(--text);
  background: var(--surface-raised);
}
input[type="range"] { width: 100%; height: 44px; margin: -13px 0; accent-color: var(--accent); }
.check-field { min-height: 44px; display: flex; align-items: center; gap: 9px; color: var(--muted); font-size: 12px; cursor: pointer; }
.check-field input { width: 17px; height: 17px; accent-color: var(--accent); }
#floyd-options { display: grid; gap: 12px; }
#floyd-options[hidden] { display: none; }

.workspace { min-width: 0; overflow-x: clip; padding: 34px clamp(24px, 4vw, 64px) 30px; }
.workspace-header { max-width: 1160px; margin: 0 auto 28px; display: flex; justify-content: space-between; align-items: end; gap: 24px; }
.workspace-header h2 { max-width: 650px; margin-top: 8px; font-size: clamp(20px, 2.2vw, 30px); line-height: 1.25; letter-spacing: -0.04em; text-wrap: balance; }
.status { min-height: 20px; max-width: 320px; color: var(--muted); font-size: 12px; text-align: right; }
.status[data-tone="success"] { color: var(--success); }
.status[data-tone="error"] { color: var(--danger); }

.comparison { max-width: 1160px; min-height: min(620px, 65vh); margin: auto; display: grid; grid-template-columns: minmax(280px, 1fr) 36px minmax(280px, 1fr); align-items: center; gap: 14px; }
.canvas-card { min-width: 0; margin: 0; }
.canvas-card figcaption { display: flex; justify-content: space-between; margin-bottom: 10px; color: var(--muted); font-size: 11px; }
.canvas-card figcaption span { color: var(--text); font-weight: 650; }
.canvas-card canvas { display: block; width: 100%; height: auto; border: 1px solid var(--border); border-radius: 20px; background: #efede7; box-shadow: 0 1px 2px #0009, 0 12px 32px #0004; }
.result-card { display: grid; justify-items: center; }
.result-card figcaption { width: 100%; }
.result-surface { --canvas-scale: 1; position: relative; width: calc(var(--canvas-scale) * 100%); max-width: none; touch-action: manipulation; }
.result-surface canvas { image-rendering: pixelated; }
.result-surface #interaction-canvas { position: absolute; inset: 0; border-color: transparent; background: transparent; box-shadow: none; pointer-events: none; }
.flow-mark { position: relative; z-index: 1; width: 36px; height: 36px; display: grid; place-items: center; border: 1px solid var(--border); border-radius: 50%; color: var(--accent); background: var(--surface); }

.output-bar { max-width: 1160px; margin: 28px auto 0; display: flex; align-items: center; justify-content: space-between; gap: 28px; padding: 16px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); }
.mini-output { min-width: 0; display: flex; align-items: center; gap: 16px; }
.mini-output canvas { width: 76px; height: 76px; flex: 0 0 auto; border-radius: 14px; image-rendering: pixelated; }
.mini-output h3 { margin: 6px 0; font-size: 14px; }
.stats { overflow: hidden; color: var(--quiet); font: 500 10px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace; text-overflow: ellipsis; white-space: nowrap; }
.actions { display: flex; gap: 8px; }
.actions button { min-height: 44px; padding: 0 15px; border-radius: 10px; font-size: 12px; font-weight: 650; transition: transform 120ms ease-out, background-color 150ms ease-out, border-color 150ms ease-out; }
.secondary-button { border: 1px solid var(--border-strong); color: var(--text); background: var(--surface-raised); }
.primary-button { border: 1px solid transparent; color: #111015; background: var(--accent); }
.actions button:active { transform: translateY(1px); }

button:focus-visible, select:focus-visible, input:focus-visible, .drop-zone:focus-within { outline: 2px solid var(--accent-hover); outline-offset: 2px; }

@media (hover: hover) and (pointer: fine) {
  .text-button:hover { color: var(--text); }
  .drop-zone:hover { border-color: var(--accent); background: #1c1a24; }
  .secondary-button:hover { border-color: var(--accent); background: #24212f; }
  .primary-button:hover { background: var(--accent-hover); }
  .canvas-card canvas { transition: border-color 180ms ease-out; }
  .comparison:hover .canvas-card canvas { border-color: var(--border-strong); }
}

@media (max-width: 1100px) {
  .app-shell { grid-template-columns: 300px minmax(0, 1fr); }
  .comparison { grid-template-columns: 1fr; max-width: 560px; gap: 18px; }
  .result-surface { width: min(calc(var(--canvas-scale) * 100%), 100%); }
  .flow-mark { margin: -2px auto; transform: rotate(90deg); }
  .output-bar { align-items: stretch; flex-direction: column; }
  .actions button { flex: 1; }
}

@media (max-width: 700px) {
  .app-shell { display: block; }
  .sidebar { position: relative; width: 100%; height: auto; border-right: 0; border-bottom: 1px solid var(--border); }
  .workspace { padding: 28px 16px; }
  .workspace-header { align-items: start; flex-direction: column; }
  select { font-size: 16px; }
  .status { text-align: left; }
  .comparison { min-height: 0; }
  .output-bar { padding: 14px; }
  .actions { flex-wrap: wrap; }
  .actions button { min-width: calc(50% - 4px); }
  .primary-button { flex-basis: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}