:root {
  --checker-navy: #0b1f3a;
  --checker-blue: #1d4ed8;
  --checker-blue-dark: #1e3a8a;
  --checker-sky: #eff6ff;
  --checker-mint: #ecfdf5;
  --checker-amber: #fffbeb;
  --checker-paper: #ffffff;
  --checker-bg: #f4f7fb;
  --checker-text: #172033;
  --checker-muted: #526176;
  --checker-line: #d8e0eb;
  --checker-focus: #f59e0b;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--checker-text);
  background: var(--checker-bg);
  font-family: "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.6;
}
a { color: var(--checker-blue-dark); text-underline-offset: 0.18em; }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible, button:focus-visible, select:focus-visible {
  outline: 3px solid var(--checker-focus);
  outline-offset: 3px;
}
.skip-link {
  position: absolute;
  left: 1rem;
  top: -5rem;
  z-index: 10;
  padding: .75rem 1rem;
  color: #fff;
  background: var(--checker-navy);
  border-radius: .5rem;
}
.skip-link:focus { top: 1rem; }
.checker-header { background: var(--checker-navy); color: #fff; }
.checker-nav {
  max-width: 72rem;
  min-height: 4.5rem;
  margin: 0 auto;
  padding: .75rem clamp(1rem, 4vw, 2.5rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.checker-brand { color: #fff; font-size: 1.1rem; font-weight: 800; text-decoration: none; }
.checker-nav__link { color: #dbeafe; font-weight: 650; }
.checker-hero {
  background: linear-gradient(145deg, var(--checker-navy), var(--checker-blue-dark));
  color: #fff;
  padding: clamp(2.5rem, 7vw, 5.5rem) 1rem clamp(4rem, 9vw, 7rem);
}
.checker-hero__inner { max-width: 56rem; margin: 0 auto; }
.checker-kicker {
  display: inline-flex;
  margin: 0 0 1rem;
  padding: .35rem .7rem;
  border: 1px solid rgba(255,255,255,.35);
  border-radius: 999px;
  color: #dbeafe;
  font-size: .86rem;
  font-weight: 750;
  letter-spacing: .04em;
  text-transform: uppercase;
}
h1 { max-width: 18ch; margin: 0 0 1rem; font-size: clamp(2.1rem, 6vw, 4rem); line-height: 1.07; letter-spacing: -.03em; }
.checker-lead { max-width: 44rem; margin: 0; color: #e6efff; font-size: clamp(1.05rem, 2.4vw, 1.25rem); }
.checker-main { max-width: 72rem; margin: clamp(-2.5rem, -5vw, -4rem) auto 0; padding: 0 clamp(1rem, 4vw, 2.5rem) 4rem; }
.checker-layout { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(17rem, .65fr); gap: 1.5rem; align-items: start; }
.checker-card {
  background: var(--checker-paper);
  border: 1px solid var(--checker-line);
  border-radius: 1.25rem;
  box-shadow: 0 1.2rem 3rem rgba(11,31,58,.1);
  padding: clamp(1.2rem, 4vw, 2.25rem);
}
.checker-card h2 { margin-top: 0; line-height: 1.2; }
.checker-aside { display: grid; gap: 1rem; }
.checker-note { padding: 1.1rem; border-radius: 1rem; background: var(--checker-sky); border: 1px solid #bfdbfe; }
.checker-note h2 { font-size: 1.05rem; }
.checker-note p:last-child, .checker-note ul:last-child { margin-bottom: 0; }
fieldset { min-width: 0; margin: 0 0 1.5rem; padding: 0; border: 0; }
legend { margin-bottom: .5rem; font-size: 1.05rem; font-weight: 750; }
.field-help { margin: 0 0 .65rem; color: var(--checker-muted); font-size: .94rem; }
select {
  width: 100%;
  min-height: 3.25rem;
  padding: .7rem 2.75rem .7rem .85rem;
  color: var(--checker-text);
  background: #fff;
  border: 2px solid #b8c4d5;
  border-radius: .7rem;
  font: inherit;
}
.checker-actions { display: flex; flex-wrap: wrap; gap: .75rem; }
button {
  min-height: 3rem;
  padding: .72rem 1.15rem;
  border: 2px solid transparent;
  border-radius: .7rem;
  font: inherit;
  font-weight: 750;
  cursor: pointer;
}
.button-primary { color: #fff; background: var(--checker-blue); }
.button-primary:hover { background: var(--checker-blue-dark); }
.button-secondary { color: var(--checker-navy); background: #fff; border-color: #9cacbf; }
.checker-result { margin-top: 1.75rem; padding: 1.25rem; border: 2px solid var(--checker-blue); border-radius: 1rem; background: var(--checker-sky); }
.checker-result[data-state="MANUAL_REVIEW_REQUIRED"] { border-color: #d97706; background: var(--checker-amber); }
.checker-result[data-state="VALUE_ASSESSMENT_REQUIRED"] { border-color: #059669; background: var(--checker-mint); }
.checker-result[hidden] { display: none; }
.checker-result__label { margin: 0 0 .25rem; color: var(--checker-muted); font-size: .82rem; font-weight: 800; letter-spacing: .05em; text-transform: uppercase; }
.checker-result h2 { margin-bottom: .5rem; }
.checker-result p { margin: .5rem 0; }
.checker-result ul { padding-left: 1.25rem; }
.checker-method { max-width: 72rem; margin: 0 auto; padding: 0 clamp(1rem, 4vw, 2.5rem) 4rem; }
.checker-method__grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.checker-method article { padding: 1.1rem; background: #fff; border: 1px solid var(--checker-line); border-radius: 1rem; }
.checker-method h3 { margin-top: 0; }
.checker-footer { padding: 2rem 1rem; color: #dbeafe; background: var(--checker-navy); text-align: center; }
.checker-footer a { color: #fff; }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }

@media (max-width: 780px) {
  .checker-layout { grid-template-columns: 1fr; }
  .checker-method__grid { grid-template-columns: 1fr; }
  .checker-nav { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 390px) {
  .checker-main { padding-inline: .75rem; }
  .checker-card { padding: 1rem; border-radius: 1rem; }
  .checker-actions { display: grid; }
  button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}