:root {
  --navy: #102a43;
  --blue: #075f96;
  --blue-dark: #06466f;
  --orange: #df8b28;
  --sky: #eaf5fc;
  --mint: #dff5ed;
  --green: #15805d;
  --ink: #1d2a36;
  --muted: #5c6c7a;
  --line: #d8e2ea;
  --white: #fff;
  --shadow: 0 18px 50px rgba(16, 42, 67, .12);
}

* { box-sizing: border-box; }
html { font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; color: var(--ink); background: #f4f8fb; }
body { margin: 0; min-height: 100vh; }
button, a, input { font: inherit; }
button:focus-visible, a:focus-visible, input:focus-visible { outline: 3px solid #f6b73c; outline-offset: 3px; }
.skip-link { position: fixed; left: 1rem; top: -5rem; z-index: 20; padding: .75rem 1rem; background: var(--navy); color: white; border-radius: .5rem; }
.skip-link:focus { top: 1rem; }
.app-shell { min-height: 100vh; }
.app-header { min-height: 76px; padding: .8rem clamp(1rem, 4vw, 4rem); display: flex; align-items: center; justify-content: space-between; gap: 2rem; border-bottom: 1px solid var(--line); background: var(--white); }
.brand { display: flex; align-items: center; gap: .55rem; color: var(--navy); font-size: 1.35rem; font-weight: 850; letter-spacing: -.03em; text-decoration: none; }
.brand span { padding: .25rem .55rem; border-radius: 999px; color: var(--white); background: var(--orange); font-size: .68rem; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.service-return { color: var(--blue); font-size: .78rem; font-weight: 750; text-decoration: none; }
.service-return:hover { text-decoration: underline; }
.progress-wrap { min-width: min(330px, 42vw); }
.progress-copy { display: flex; justify-content: space-between; gap: 1rem; margin-bottom: .4rem; color: var(--muted); font-size: .76rem; }
.progress-track { height: 8px; overflow: hidden; border-radius: 10px; background: #dce8ef; }
#progress-bar { height: 100%; width: 0; border-radius: inherit; background: var(--green); transition: width .25s ease; }
.app-layout { display: grid; grid-template-columns: 270px minmax(0, 1fr); min-height: calc(100vh - 76px); }
.course-index { padding: 2.2rem 1.5rem; border-right: 1px solid var(--line); background: var(--white); }
.course-index h2 { margin: 0 0 1.2rem; color: var(--navy); font-size: 1.18rem; line-height: 1.25; }
.eyebrow, .kicker { margin: 0 0 .75rem; color: var(--blue); font-size: .75rem; font-weight: 850; letter-spacing: .12em; text-transform: uppercase; }
.course-index ol { margin: 0; padding: 0; list-style: none; }
.course-index button { position: relative; width: 100%; margin: .15rem 0; padding: .72rem 2rem .72rem .75rem; border: 0; border-radius: .7rem; color: var(--muted); background: transparent; text-align: left; cursor: pointer; }
.course-index button[aria-current="step"] { color: var(--navy); background: var(--sky); font-weight: 750; }
.course-index button[data-visited="true"]::after { content: "✓"; position: absolute; right: .7rem; color: var(--green); font-weight: 900; }
main { display: flex; flex-direction: column; min-width: 0; padding: clamp(1.5rem, 4vw, 4rem); }
#screen { display: flex; flex: 1; align-items: center; max-width: 980px; width: 100%; margin: 0 auto; }
.screen-card { width: 100%; padding: clamp(1.4rem, 4vw, 3rem); border: 1px solid var(--line); border-radius: 1.2rem; background: var(--white); box-shadow: var(--shadow); }
h1 { margin: 0 0 1rem; color: var(--navy); font-size: clamp(2rem, 4.5vw, 3.7rem); line-height: 1.04; letter-spacing: -.045em; }
.lead { margin: 0; color: var(--muted); font-size: clamp(1rem, 1.6vw, 1.18rem); line-height: 1.65; }
.result-card, .model-card, .final-callout { margin-top: 1.4rem; padding: 1.05rem 1.2rem; border-radius: .9rem; background: var(--mint); line-height: 1.55; }
.result-card strong, .final-callout strong { color: var(--navy); }
.result-card p, .model-card p { margin: .4rem 0 0; }
.rule-list, .plain-list { display: grid; gap: .6rem; margin: 1.4rem 0 0; padding-left: 1.3rem; line-height: 1.55; }
.steps { display: grid; gap: .7rem; margin: 1.4rem 0 0; padding: 0; list-style: none; }
.steps li { display: grid; grid-template-columns: 38px 1fr; align-items: center; gap: .85rem; padding: .85rem 1rem; border: 1px solid var(--line); border-radius: .8rem; background: #fbfdfe; line-height: 1.5; }
.step-number, .option-letter { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 11px; color: white; background: var(--blue); font-weight: 850; }
.callout { margin: 1rem 0 0; padding: .85rem 1rem; border-left: 4px solid var(--orange); border-radius: 0 .65rem .65rem 0; color: var(--navy); background: #fff7e8; line-height: 1.5; }
.data-grid, .checklist { display: grid; gap: .65rem; margin-top: 1.4rem; }
.data-row, .checklist label { display: flex; align-items: flex-start; gap: .75rem; padding: .8rem .9rem; border: 1px solid var(--line); border-radius: .75rem; background: #fbfdfe; cursor: pointer; line-height: 1.45; }
.data-row input, .checklist input { flex: 0 0 auto; width: 1.1rem; height: 1.1rem; margin-top: .15rem; accent-color: var(--green); }
.data-row strong { display: inline-grid; place-items: center; width: 1.5rem; height: 1.5rem; margin-right: .5rem; border-radius: 50%; color: white; background: var(--blue); font-size: .78rem; }
.checked { border-color: #a5d7c4 !important; background: #f1fbf6 !important; }
.message-card, .model-card { margin-top: 1.4rem; border: 1px solid #c8dfec; background: #f2f9fd; }
.model-card { border-color: #a5d7c4; background: var(--mint); }
.card-label { display: block; margin-bottom: .45rem; color: var(--blue-dark); font-size: .75rem; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.message-card p, .model-card p { margin: 0; line-height: 1.6; }
.two-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin-top: 1.1rem; }
.two-columns section { padding: .95rem 1rem; border: 1px solid var(--line); border-radius: .85rem; }
.two-columns h2 { margin: 0; color: var(--navy); font-size: 1rem; }
.plain-list { margin-top: .7rem; font-size: .93rem; }
.plain-list.missing li::marker { color: var(--orange); }
.decision-list { display: grid; gap: .7rem; margin-top: 1.4rem; }
.decision-option { display: grid; grid-template-columns: 34px 1fr; align-items: center; gap: .8rem; padding: .85rem; border: 1px solid var(--line); border-radius: .8rem; color: var(--ink); background: #fbfdfe; text-align: left; cursor: pointer; line-height: 1.45; }
.decision-option:hover, .decision-option.selected { border-color: var(--blue); background: var(--sky); }
.feedback { min-height: 1.5rem; margin: .9rem 0 0; padding: .8rem 1rem; border-radius: .7rem; font-weight: 700; line-height: 1.5; }
.feedback.success { color: #0f5a42; background: var(--mint); }
.feedback.notice { color: #7a4a00; background: #fff7e8; }
.screen-controls { display: flex; align-items: center; justify-content: space-between; gap: 1rem; max-width: 980px; width: 100%; margin: 1.6rem auto 0; padding-top: 1.2rem; border-top: 1px solid var(--line); }
#screen-position { color: var(--muted); font-size: .85rem; }
.button { min-height: 46px; padding: .72rem 1.1rem; border: 1px solid transparent; border-radius: .7rem; font-weight: 750; cursor: pointer; }
.button-primary { color: white; background: var(--blue); }
.button-primary:hover { background: var(--blue-dark); }
.button-secondary { color: var(--navy); border-color: var(--line); background: white; }
.button:disabled { opacity: .42; cursor: not-allowed; }

@media (max-width: 850px) {
  .app-header { gap: 1rem; }
  .brand { font-size: 1.12rem; }
  .brand span { display: none; }
  .progress-wrap { min-width: 130px; }
  .progress-copy span:last-child { display: none; }
  .app-layout { grid-template-columns: minmax(0, 1fr); min-width: 0; }
  .course-index { min-width: 0; overflow: hidden; padding: .7rem 1rem; border-right: 0; border-bottom: 1px solid var(--line); }
  .course-index .eyebrow, .course-index h2 { display: none; }
  .course-index ol { display: flex; max-width: 100%; min-width: 0; overflow-x: auto; gap: .3rem; }
  .course-index li { min-width: max-content; }
  .course-index button { width: auto; }
  main { padding: 1rem; }
  .screen-card { padding: 1.25rem; border-radius: .95rem; }
  .two-columns { grid-template-columns: 1fr; }
}

@media (max-width: 520px) {
  .app-header { min-height: 68px; padding: .7rem .9rem; }
  .progress-wrap { min-width: 105px; }
  h1 { font-size: clamp(1.9rem, 10vw, 2.8rem); }
  .screen-controls { flex-wrap: wrap; }
  #screen-position { order: -1; width: 100%; text-align: center; }
  .screen-controls .button { flex: 1; }
}

@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition-duration: .01ms !important; } }