:root {
  color-scheme: dark;
  --bg: #080a0f;
  --panel: #10131a;
  --panel-2: #151923;
  --line: #2a303d;
  --line-strong: #3d4658;
  --text: #f5f7fb;
  --muted: #949baa;
  --cyan: #68e2ff;
  --coral: #ff6b57;
  --lime: #c7f464;
  --violet: #a795ff;
  --font-sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

html { min-width: 320px; background: var(--bg); }

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 85% -10%, rgba(104, 226, 255, 0.1), transparent 30%),
    radial-gradient(circle at -10% 65%, rgba(167, 149, 255, 0.08), transparent 25%),
    var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.5;
}

button, input, select { font: inherit; }
button, label, select, input[type="range"] { -webkit-tap-highlight-color: transparent; }

button:focus-visible, select:focus-visible, input:focus-visible, .drop-zone:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.app-shell { width: min(1600px, 100%); margin: 0 auto; padding: 22px; }

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 6px 2px 20px;
}

.brand-block { display: flex; align-items: center; gap: 14px; }
.brand-mark {
  width: 40px;
  aspect-ratio: 1;
  border: 4px solid var(--text);
  border-radius: 50%;
  position: relative;
  background: linear-gradient(90deg, var(--coral) 0 50%, var(--cyan) 50%);
  box-shadow: inset 0 0 0 8px var(--bg);
}
.brand-mark::after {
  content: "";
  position: absolute;
  inset: 50% -7px auto;
  height: 3px;
  background: var(--text);
  transform: translateY(-50%);
}

.eyebrow {
  margin: 0 0 3px;
  color: var(--muted);
  font: 700 0.75rem/1.2 var(--font-mono);
  letter-spacing: 0.15em;
}

h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 0; font-size: clamp(1.25rem, 2vw, 1.75rem); line-height: 1.1; letter-spacing: -0.03em; }

.privacy-badge {
  display: flex;
  align-items: center;
  max-width: 570px;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid rgba(199, 244, 100, 0.32);
  border-radius: 999px;
  background: rgba(199, 244, 100, 0.06);
  color: #e8f6c6;
  font-size: 0.875rem;
}

.privacy-dot { width: 8px; height: 8px; flex: 0 0 auto; border-radius: 50%; background: var(--lime); box-shadow: 0 0 14px rgba(199, 244, 100, 0.75); }

.workspace {
  min-height: calc(100vh - 154px);
  display: grid;
  grid-template-columns: 380px minmax(0, 1fr);
  border: 1px solid var(--line);
  border-radius: 18px;
  overflow: hidden;
  background: rgba(16, 19, 26, 0.86);
  box-shadow: 0 30px 90px rgba(0, 0, 0, 0.28);
}

.control-panel { padding: 24px; border-right: 1px solid var(--line); background: rgba(11, 14, 20, 0.82); }

.step-heading { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.step-heading > span { color: var(--cyan); font: 700 0.75rem var(--font-mono); }
.step-heading h2 { margin: 0; font-size: 1rem; letter-spacing: -0.01em; }

.drop-zone {
  min-height: 178px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  cursor: pointer;
  border: 1px dashed var(--line-strong);
  border-radius: 14px;
  background:
    linear-gradient(135deg, rgba(104, 226, 255, 0.06), transparent 45%),
    var(--panel);
  text-align: center;
  transition: border-color 160ms ease, transform 160ms ease, background 160ms ease;
}
.drop-zone:hover, .drop-zone.is-dragging { border-color: var(--cyan); background-color: #131923; transform: translateY(-1px); }
.drop-zone input { position: absolute; width: 1px; height: 1px; opacity: 0; pointer-events: none; }
.drop-zone strong { font-size: 1rem; }
.drop-zone > span:not(.upload-icon) { color: var(--muted); font-size: 0.875rem; }
.drop-zone small { margin-top: 8px; color: var(--cyan); font: 700 0.72rem var(--font-mono); letter-spacing: 0.08em; }

.upload-icon { width: 40px; height: 40px; display: grid; place-items: center; margin-bottom: 5px; border-radius: 50%; background: rgba(104, 226, 255, 0.09); color: var(--cyan); }
.upload-icon svg, button svg, a svg { width: 20px; height: 20px; flex: 0 0 auto; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.file-summary { display: grid; grid-template-columns: 50px minmax(0, 1fr) 34px; align-items: center; gap: 11px; padding: 10px; border: 1px solid var(--line); border-radius: 12px; background: var(--panel); }
.file-thumb-wrap { width: 50px; height: 50px; overflow: hidden; border-radius: 8px; background: #050609; }
.file-thumb-wrap img { width: 100%; height: 100%; object-fit: cover; }
.file-copy { min-width: 0; display: flex; flex-direction: column; }
.file-copy strong { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 0.875rem; }
.file-copy small { color: var(--muted); font: 0.72rem var(--font-mono); }
.icon-button { width: 34px; height: 34px; display: grid; place-items: center; border: 0; border-radius: 8px; background: transparent; color: var(--muted); cursor: pointer; }
.icon-button:hover { color: var(--text); background: var(--panel-2); }

.divider { height: 1px; margin: 22px 0; background: var(--line); }
.field-group { margin-bottom: 20px; }
.field-group > label, .field-label-row label, .type-fieldset legend { color: var(--text); font-size: 0.875rem; font-weight: 650; }
.field-note { margin: 7px 0 0; color: var(--muted); font-size: 0.78rem; }
.field-label-row { display: flex; align-items: center; justify-content: space-between; margin-bottom: 10px; }
.field-label-row output { min-width: 44px; color: var(--cyan); font: 700 0.8rem var(--font-mono); text-align: right; }

.select-wrap { position: relative; margin-top: 9px; }
.select-wrap select { width: 100%; min-height: 44px; padding: 0 40px 0 12px; border: 1px solid var(--line-strong); border-radius: 10px; appearance: none; background: var(--panel-2); color: var(--text); cursor: pointer; }
.select-wrap svg { position: absolute; right: 13px; top: 50%; width: 16px; transform: translateY(-50%); fill: none; stroke: var(--muted); stroke-width: 1.8; pointer-events: none; }

input[type="range"] { width: 100%; height: 24px; margin: 0; appearance: none; background: transparent; cursor: pointer; }
input[type="range"]::-webkit-slider-runnable-track { height: 5px; border-radius: 999px; background: linear-gradient(90deg, var(--cyan) var(--range-progress, 100%), var(--line-strong) var(--range-progress, 100%)); }
input[type="range"]::-webkit-slider-thumb { width: 20px; height: 20px; margin-top: -7.5px; border: 3px solid var(--bg); border-radius: 50%; appearance: none; background: var(--cyan); box-shadow: 0 0 0 1px var(--cyan); }
input[type="range"]::-moz-range-track { height: 5px; border-radius: 999px; background: var(--line-strong); }
input[type="range"]::-moz-range-progress { height: 5px; border-radius: 999px; background: var(--cyan); }
input[type="range"]::-moz-range-thumb { width: 16px; height: 16px; border: 3px solid var(--bg); border-radius: 50%; background: var(--cyan); box-shadow: 0 0 0 1px var(--cyan); }
.range-labels { display: flex; justify-content: space-between; color: var(--muted); font: 0.68rem var(--font-mono); }
.strength-presets { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 5px; margin: 5px 0 7px; }
.strength-presets button { min-width: 0; min-height: 31px; padding: 0 3px; border: 1px solid var(--line); border-radius: 7px; background: var(--panel); color: var(--muted); font: 700 0.66rem var(--font-mono); cursor: pointer; }
.strength-presets button:hover { border-color: var(--line-strong); color: var(--text); }
.strength-presets button.is-active { border-color: var(--cyan); background: rgba(104, 226, 255, 0.1); color: var(--cyan); }

.type-fieldset { display: grid; gap: 7px; margin: 0 0 20px; padding: 0; border: 0; }
.type-fieldset legend { margin-bottom: 9px; }
.fieldset-note { margin: -3px 0 4px; color: var(--muted); font-size: 0.76rem; line-height: 1.45; }
.check-row { display: grid; grid-template-columns: 20px 1fr; gap: 10px; align-items: center; min-height: 46px; padding: 7px 9px; border: 1px solid transparent; border-radius: 9px; cursor: pointer; }
.check-row:hover { border-color: var(--line); background: var(--panel); }
.check-row input { position: absolute; opacity: 0; pointer-events: none; }
.check-row > span:last-child { display: flex; flex-direction: column; }
.check-row strong { font-size: 0.84rem; }
.check-row small { color: var(--muted); font-size: 0.72rem; }
.check-ui { width: 18px; height: 18px; display: grid; place-items: center; border: 1px solid var(--line-strong); border-radius: 5px; background: var(--panel-2); }
.check-row input:checked + .check-ui { border-color: var(--cyan); background: var(--cyan); }
.check-row input:checked + .check-ui::after { content: ""; width: 8px; height: 4px; border: solid var(--bg); border-width: 0 0 2px 2px; transform: rotate(-45deg) translate(1px, -1px); }
.check-row input:focus-visible + .check-ui { outline: 2px solid var(--cyan); outline-offset: 3px; }

.primary-button { width: 100%; min-height: 48px; display: flex; align-items: center; justify-content: center; gap: 9px; border: 0; border-radius: 10px; background: var(--text); color: var(--bg); font-weight: 750; text-decoration: none; cursor: pointer; transition: background 160ms ease, transform 160ms ease; }
.primary-button[aria-disabled="false"]:hover { background: var(--cyan); transform: translateY(-1px); }
.primary-button[aria-disabled="true"] { cursor: not-allowed; opacity: 0.38; }
.trust-line { margin: 12px 0 0; color: var(--muted); font: 0.7rem/1.4 var(--font-mono); text-align: center; }

.results-panel { min-width: 0; padding: 24px; background-image: linear-gradient(rgba(255,255,255,.018) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.018) 1px, transparent 1px); background-size: 24px 24px; }
.results-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 18px; }
.results-toolbar h2 { margin: 0; font-size: clamp(1.25rem, 2vw, 1.7rem); letter-spacing: -0.03em; }
.results-intro { max-width: 680px; margin: 7px 0 0; color: var(--muted); font-size: 0.82rem; line-height: 1.45; }
.status-pill { display: flex; align-items: center; gap: 8px; padding: 7px 10px; border: 1px solid var(--line); border-radius: 999px; background: rgba(8, 10, 15, 0.82); color: var(--muted); font-size: 0.75rem; white-space: nowrap; }
.status-pill span { width: 7px; height: 7px; border-radius: 50%; background: var(--muted); }
.status-pill.is-ready { color: #e8f6c6; border-color: rgba(199, 244, 100, 0.28); }
.status-pill.is-ready span { background: var(--lime); box-shadow: 0 0 12px rgba(199, 244, 100, .7); }

.empty-state { min-height: 570px; display: grid; place-items: center; align-content: center; padding: 30px; border: 1px solid var(--line); border-radius: 14px; background: rgba(8, 10, 15, 0.55); text-align: center; }
.empty-state h3 { margin: 22px 0 6px; font-size: 1.2rem; }
.empty-state p { margin: 0; color: var(--muted); }
.spectrum-orbit { width: 136px; aspect-ratio: 1; position: relative; border: 1px solid var(--line-strong); border-radius: 50%; }
.spectrum-orbit::before, .spectrum-orbit::after { content: ""; position: absolute; inset: 24px; border: 1px solid var(--line); border-radius: 50%; }
.spectrum-orbit::after { inset: 51px; background: var(--text); box-shadow: 0 0 25px rgba(245, 247, 251, 0.2); }
.spectrum-orbit span { position: absolute; width: 13px; height: 13px; border-radius: 50%; box-shadow: 0 0 18px currentColor; }
.spectrum-orbit span:nth-child(1) { left: 16px; top: 28px; color: var(--coral); background: currentColor; }
.spectrum-orbit span:nth-child(2) { right: 9px; top: 55px; color: var(--cyan); background: currentColor; }
.spectrum-orbit span:nth-child(3) { left: 47px; bottom: 5px; color: var(--lime); background: currentColor; }
.spectrum-orbit span:nth-child(4) { left: 8px; bottom: 34px; color: var(--violet); background: currentColor; }

.result-grid { display: grid; grid-template-columns: 1fr; gap: 14px; }
.result-card { min-width: 0; overflow: hidden; border: 1px solid var(--line); border-radius: 13px; background: rgba(12, 15, 21, 0.94); }
.result-card::before { content: ""; display: block; height: 3px; background: var(--card-accent, var(--cyan)); }
.card-heading { min-height: 58px; display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 10px 12px; }
.card-heading > div { min-width: 0; display: flex; align-items: baseline; gap: 8px; }
.card-index { color: var(--muted); font: 0.68rem var(--font-mono); }
.card-title { overflow: hidden; margin: 0; font-size: 0.95rem; text-overflow: ellipsis; white-space: nowrap; }
.download-button { display: flex; align-items: center; gap: 5px; min-height: 32px; padding: 0 9px; border: 1px solid var(--line-strong); border-radius: 8px; background: transparent; color: var(--muted); font: 700 0.7rem var(--font-mono); text-decoration: none; cursor: pointer; }
.download-button:hover { border-color: var(--cyan); color: var(--cyan); }
.download-button svg { width: 15px; }
.comparison-strip { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); border-block: 1px solid var(--line); background: #050609; }
.compare-pane { min-width: 0; margin: 0; border-right: 1px solid var(--line); }
.compare-pane:last-child { border-right: 0; }
.compare-pane figcaption { padding: 7px 10px; border-bottom: 1px solid var(--line); color: var(--muted); font: 700 0.68rem var(--font-mono); letter-spacing: 0.06em; text-transform: uppercase; }
.difference-pane figcaption { color: var(--lime); }
.canvas-wrap { position: relative; display: grid; place-items: center; min-height: 180px; overflow: hidden; background: #050609; }
.canvas-wrap canvas { display: block; width: 100%; height: 100%; max-height: 360px; object-fit: contain; }
.difference-note { margin: 0; padding: 9px 12px 0; color: #d7e8ac; font-size: 0.74rem; line-height: 1.45; }
.card-meta { display: flex; justify-content: space-between; gap: 10px; padding: 9px 12px; color: var(--muted); font: 0.68rem var(--font-mono); }

.result-card[data-type="protan"] { --card-accent: var(--coral); }
.result-card[data-type="deutan"] { --card-accent: var(--lime); }
.result-card[data-type="tritan"] { --card-accent: var(--cyan); }
.result-card[data-type="achromatopsia"] { --card-accent: var(--violet); }

footer { display: flex; justify-content: space-between; gap: 20px; padding: 16px 3px 0; color: var(--muted); font: 0.7rem/1.45 var(--font-mono); }
footer p { margin: 0; }
.footer-nav { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px 16px; }
.footer-nav a { color: var(--muted); text-underline-offset: 3px; }
.footer-nav a:hover, .footer-nav a:focus-visible, .footer-nav a[aria-current="page"] { color: var(--cyan); }

.content-page-shell { width: min(920px, 100%); min-height: 100vh; margin: 0 auto; padding: 22px; display: flex; flex-direction: column; }
.content-page-shell .brand-block { color: var(--text); text-decoration: none; }
.content-page { flex: 1; padding: clamp(28px, 6vw, 64px); border: 1px solid var(--line); border-radius: 18px; background: rgba(12, 15, 21, 0.94); box-shadow: 0 22px 70px rgba(0, 0, 0, 0.22); }
.content-page .page-kicker { margin-bottom: 12px; color: var(--cyan); font: 700 0.75rem/1.2 var(--font-mono); letter-spacing: 0.15em; text-transform: uppercase; }
.content-page h1 { margin-bottom: 24px; font-size: clamp(2rem, 7vw, 4rem); }
.content-page h2 { margin: 30px 0 10px; font-size: 1.05rem; }
.content-page p { max-width: 68ch; color: #c8ced9; }
.content-page a { color: var(--cyan); text-underline-offset: 3px; }
.content-page .signature { margin-top: 38px; color: var(--text); font-weight: 750; }
.contact-address { display: inline-block; margin: 8px 0 20px; font: 700 clamp(1rem, 4vw, 1.35rem)/1.4 var(--font-mono); overflow-wrap: anywhere; }

.editorial { margin-top: clamp(44px, 7vw, 96px); }
.editorial-heading, .section-heading { max-width: 800px; margin-bottom: 24px; }
.editorial-heading h2, .section-heading h2 { margin-bottom: 10px; font-size: clamp(1.65rem, 4vw, 2.65rem); line-height: 1.08; letter-spacing: -0.035em; }
.editorial-heading > p:last-child, .section-heading > p:last-child { margin: 0; color: var(--muted); font-size: 0.95rem; line-height: 1.65; }
.section-heading { margin-top: clamp(48px, 7vw, 82px); }
.guide-grid { display: grid; gap: 14px; }
.guide-grid--two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.guide-card, .method-card, .output-guide article { border: 1px solid var(--line); border-radius: 14px; background: rgba(12, 15, 21, 0.86); }
.guide-card { padding: clamp(20px, 3vw, 30px); }
.guide-card h3, .method-card h3, .output-guide h3 { margin-bottom: 10px; font-size: 1.05rem; }
.guide-card p, .method-card p, .output-guide p { color: #bbc2ce; line-height: 1.65; }
.guide-index { margin-bottom: 12px !important; color: var(--cyan) !important; font: 700 0.7rem/1.3 var(--font-mono); letter-spacing: 0.09em; }
.guide-note, .inline-note { padding: 12px 14px; border-left: 3px solid var(--lime); background: rgba(199, 244, 100, 0.055); color: #d7e8ac !important; }
.guide-note { margin: 20px 0 0; }
.plain-list { display: grid; gap: 9px; margin: 0; padding-left: 20px; color: #bbc2ce; }
.step-list { display: grid; gap: 12px; margin: 0; padding: 0; list-style: none; }
.step-list li { display: grid; grid-template-columns: 30px 1fr; gap: 10px; align-items: start; }
.step-list span { width: 28px; height: 28px; display: grid; place-items: center; border: 1px solid var(--line-strong); border-radius: 50%; color: var(--cyan); font: 700 0.7rem var(--font-mono); }
.step-list p { margin: 2px 0 0; }
.method-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.method-card { min-width: 0; padding: 20px; }
.method-card p { margin-bottom: 0; font-size: 0.86rem; }
.method-year, .output-guide article > span { display: block; margin-bottom: 13px; color: var(--cyan); font: 700 0.68rem var(--font-mono); letter-spacing: 0.1em; }
.inline-note { margin: 14px 0 0; font-size: 0.83rem; line-height: 1.55; }
.output-guide { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }
.output-guide article { padding: 20px; }
.output-guide p { margin-bottom: 0; font-size: 0.86rem; }
.output-guide article:last-child { border-color: rgba(199, 244, 100, 0.3); }
.output-guide article:last-child > span { color: var(--lime); }
.limits-grid { margin-top: clamp(48px, 7vw, 82px); }
.faq-heading { margin-bottom: 18px; }
.faq-list { border-top: 1px solid var(--line); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { position: relative; padding: 19px 46px 19px 2px; color: var(--text); font-weight: 700; cursor: pointer; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; position: absolute; right: 6px; top: 50%; color: var(--cyan); font: 400 1.4rem var(--font-mono); transform: translateY(-50%); }
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { max-width: 820px; margin: -4px 0 20px; color: #bbc2ce; line-height: 1.65; }
.source-notes { margin-top: 46px; padding: clamp(20px, 3vw, 28px); border: 1px solid var(--line); border-radius: 14px; background: rgba(104, 226, 255, 0.035); }
.source-notes h2 { margin-bottom: 8px; font-size: 1.05rem; }
.source-notes > p { max-width: 850px; margin-bottom: 16px; color: var(--muted); font-size: 0.84rem; line-height: 1.6; }
.source-links { display: flex; flex-wrap: wrap; gap: 8px 16px; }
.source-links a { color: var(--cyan); font: 0.72rem/1.5 var(--font-mono); text-underline-offset: 3px; }

@media (max-width: 980px) {
  .app-shell { padding: 14px; }
  .topbar { align-items: flex-start; flex-direction: column; }
  .privacy-badge { max-width: none; border-radius: 13px; }
  .workspace { grid-template-columns: 1fr; }
  .control-panel { border-right: 0; border-bottom: 1px solid var(--line); }
  .results-panel { padding: 18px; }
  .empty-state { min-height: 390px; }
  .method-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .app-shell { padding: 10px; }
  .topbar { padding: 7px 2px 14px; gap: 13px; }
  .brand-mark { width: 34px; }
  .privacy-badge { align-items: flex-start; font-size: 0.8rem; }
  .workspace { border-radius: 14px; }
  .control-panel, .results-panel { padding: 16px; }
  .drop-zone { min-height: 154px; }
  .results-toolbar { align-items: flex-start; flex-direction: column; gap: 11px; }
  .result-grid { grid-template-columns: 1fr; }
  .comparison-strip { grid-template-columns: 1fr; }
  .compare-pane { border-right: 0; border-bottom: 1px solid var(--line); }
  .compare-pane:last-child { border-bottom: 0; }
  .canvas-wrap { min-height: 180px; }
  .card-meta { align-items: flex-start; flex-direction: column; gap: 4px; }
  footer { align-items: flex-start; flex-direction: column; gap: 9px; padding-inline: 4px; }
  .footer-nav { justify-content: flex-start; }
  .content-page-shell { padding: 10px; }
  .content-page { padding: 26px 18px; border-radius: 14px; }
  .guide-grid--two, .method-grid, .output-guide { grid-template-columns: 1fr; }
  .editorial { margin-top: 44px; }
  .section-heading, .limits-grid { margin-top: 44px; }
  .guide-card, .method-card, .output-guide article { padding: 18px; }
  .source-links { flex-direction: column; gap: 8px; }
}

@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; }
}