:root {
  --navy: #01017c;
  --cyan: #22a9f8;
  --cyan-deep: #087fbd;
  --soft: #eaf8ff;
  --ink: #10206f;
  --muted: #475569;
  --line: rgba(1, 1, 124, 0.14);
  --warning: #fff8e8;
  --warning-ink: #7c4a03;
  --success: #0f766e;
  --surface: #ffffff;
}

* {
  box-sizing: border-box;
}

html {
  background: #ffffff;
  color: var(--ink);
  font-family:
    system-ui,
    -apple-system,
    "Segoe UI",
    Roboto,
    sans-serif;
}

body {
  margin: 0;
  min-width: 0;
  background: linear-gradient(180deg, #edf8ff 0, #ffffff 34rem);
  line-height: 1.6;
}

button,
select,
input {
  font: inherit;
}

a {
  color: var(--navy);
}

.ortolan-watermark {
  position: fixed;
  right: 16px;
  bottom: 16px;
  z-index: 1000;
  display: inline-block;
  padding: 8px 12px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 0 18px 4px rgba(34, 169, 248, 0.34);
  line-height: 0;
  transition:
    box-shadow 180ms ease,
    transform 180ms ease;
}

.ortolan-watermark:hover,
.ortolan-watermark:focus-visible {
  outline: 3px solid rgba(34, 169, 248, 0.34);
  box-shadow: 0 0 24px 6px rgba(34, 169, 248, 0.48);
  transform: scale(1.03);
}

.ortolan-watermark img {
  display: block;
  width: 100px;
  height: auto;
}

.disclaimer-banner {
  position: sticky;
  top: 0;
  z-index: 20;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid #fde6a7;
  background: rgba(255, 248, 232, 0.96);
  color: var(--warning-ink);
  font-size: 0.86rem;
  font-weight: 700;
  text-align: center;
  backdrop-filter: blur(8px);
}

.app-shell {
  width: min(760px, calc(100% - 2rem));
  margin: 2rem auto;
  min-width: 0;
}

.progress {
  height: 8px;
  border-radius: 999px;
  background: rgba(34, 169, 248, 0.16);
}

.progress-bar {
  display: block;
  width: 25%;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--navy), var(--cyan));
  transition: width 220ms ease;
}

.step-count {
  margin: 0.55rem 0 1rem;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-align: right;
  text-transform: uppercase;
}

.step {
  min-width: 0;
  padding: clamp(1.25rem, 4vw, 2.5rem);
  border: 1px solid var(--line);
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 22px 70px rgba(1, 1, 124, 0.11);
}

.step.active {
  animation: reveal 260ms ease;
}

@keyframes reveal {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.eyebrow {
  margin: 0 0 0.35rem;
  color: var(--cyan-deep);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h2 {
  margin: 0 0 1rem;
  color: var(--navy);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.65rem, 5vw, 2.25rem);
  line-height: 1.15;
}

h2:focus {
  outline: none;
}

p {
  color: var(--muted);
}

.form-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 1rem;
  margin: 1.5rem 0;
}

.field,
.mode-fieldset {
  min-width: 0;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #f8fbff;
}

.field > span,
.mode-fieldset legend {
  color: var(--ink);
  font-size: 0.9rem;
  font-weight: 800;
}

.field select {
  width: 100%;
  margin-top: 0.55rem;
  padding: 0.72rem;
  border: 1px solid rgba(1, 1, 124, 0.24);
  border-radius: 9px;
  background: #ffffff;
  color: var(--ink);
}

.mode-fieldset {
  display: grid;
  gap: 0.55rem;
  margin: 0;
}

.mode-fieldset label {
  display: flex;
  align-items: flex-start;
  gap: 0.55rem;
  color: var(--muted);
  font-size: 0.92rem;
}

.mode-fieldset input {
  margin-top: 0.28rem;
  accent-color: var(--cyan-deep);
}

.notice,
.distance-card,
.age-context {
  padding: 1rem;
  border-left: 4px solid var(--cyan);
  border-radius: 0 12px 12px 0;
  background: var(--soft);
  color: var(--ink);
}

.form-error {
  min-height: 1.5rem;
  margin: 0.7rem 0;
  color: #b42318;
  font-weight: 700;
}

.calibration-stage {
  display: grid;
  min-width: 0;
  min-height: 230px;
  margin: 1.5rem 0 1rem;
  padding: 1.25rem;
  place-items: center;
  overflow-x: auto;
  border: 1px dashed rgba(34, 169, 248, 0.5);
  border-radius: 16px;
  background: #f8fbff;
}

.card-guide {
  display: grid;
  width: 300px;
  aspect-ratio: 85.6 / 53.98;
  flex: none;
  place-content: center;
  border: 2px solid rgba(255, 255, 255, 0.7);
  border-radius: 15px;
  background: linear-gradient(135deg, var(--navy), var(--cyan));
  box-shadow: 0 14px 34px rgba(1, 1, 124, 0.2);
  color: #ffffff;
  text-align: center;
}

.card-guide span {
  font-size: 1rem;
  font-weight: 800;
}

.card-guide small {
  opacity: 0.82;
}

.slider-label {
  display: block;
  margin-bottom: 0.4rem;
  color: var(--ink);
  font-size: 0.9rem;
  font-weight: 800;
}

.slider {
  width: 100%;
  accent-color: var(--cyan-deep);
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0.78rem 1.15rem;
  border: 1px solid transparent;
  border-radius: 11px;
  font-weight: 800;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}

.button:focus-visible,
.reading-line:focus-visible,
select:focus-visible,
input:focus-visible {
  outline: 3px solid rgba(34, 169, 248, 0.38);
  outline-offset: 3px;
}

.button.primary {
  background: var(--cyan);
  color: #062b47;
  box-shadow: 0 10px 24px rgba(34, 169, 248, 0.25);
}

.button.primary:hover {
  background: #3bb6ff;
}

.button.secondary {
  border-color: rgba(1, 1, 124, 0.2);
  background: #ffffff;
  color: var(--navy);
}

.button:disabled {
  box-shadow: none;
  cursor: not-allowed;
  opacity: 0.48;
}

.button.full {
  width: 100%;
}

.text-button {
  width: 100%;
  margin-top: 0.75rem;
  background: transparent;
  color: var(--navy);
}

.distance-card {
  display: grid;
  gap: 0.2rem;
  margin-bottom: 1rem;
}

.distance-card span {
  color: var(--muted);
  font-size: 0.9rem;
}

.reading-chart {
  display: grid;
  min-width: 0;
  gap: 0.45rem;
  margin-top: 1.5rem;
}

.reading-line {
  display: grid;
  grid-template-columns: 3.2rem minmax(0, 1fr);
  min-width: 0;
  align-items: center;
  gap: 0.75rem;
  padding: 0.68rem 0.8rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #ffffff;
  color: #0f172a;
  cursor: pointer;
  text-align: left;
}

.reading-line:hover {
  border-color: rgba(34, 169, 248, 0.7);
  background: #f8fcff;
}

.reading-line[aria-pressed="true"] {
  border-color: var(--cyan-deep);
  background: var(--soft);
  box-shadow: 0 0 0 2px rgba(34, 169, 248, 0.18);
}

.line-label {
  align-self: start;
  padding: 0.24rem 0.35rem;
  border-radius: 7px;
  background: rgba(1, 1, 124, 0.07);
  color: var(--navy);
  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0.04em;
  text-align: center;
}

.line-sample {
  min-width: 0;
  line-height: 1.25;
}

.selection-status {
  min-height: 1.5rem;
  color: var(--success);
  font-weight: 800;
}

.result-card {
  display: grid;
  gap: 0.65rem;
  margin: 1.2rem 0;
  padding: clamp(1.2rem, 4vw, 2rem);
  border: 1px solid rgba(34, 169, 248, 0.3);
  border-radius: 18px;
  background: linear-gradient(135deg, #edf8ff, #ffffff);
  text-align: center;
}

.result-level {
  color: var(--cyan-deep);
  font-size: clamp(2.4rem, 10vw, 4.2rem);
  font-weight: 900;
  line-height: 1;
}

.result-card strong {
  color: var(--navy);
  font-size: 1.2rem;
}

.result-card p {
  margin: 0;
}

.age-context {
  margin: 1rem 0;
}

.result-caveat {
  font-size: 0.92rem;
}

.result-links {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.6rem;
  margin-top: 0.75rem;
}

.result-links a {
  min-width: 0;
  padding: 0.75rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #ffffff;
  font-size: 0.84rem;
  font-weight: 800;
  text-align: center;
  text-decoration: none;
}

.references {
  width: min(760px, calc(100% - 2rem));
  margin: 2rem auto 7rem;
  padding: clamp(1rem, 4vw, 1.5rem);
  border-radius: 16px;
  background: #f5f7fb;
  color: var(--muted);
  font-size: 0.88rem;
}

.references h3 {
  margin: 0 0 0.6rem;
  color: var(--navy);
  font-size: 1rem;
}

.references p {
  margin: 0 0 0.8rem;
}

.references ol {
  margin: 0;
  padding-left: 1.25rem;
}

.references li {
  margin-bottom: 0.6rem;
}

.references a {
  font-weight: 800;
}

.footer-disclaimer {
  margin-top: 1rem !important;
  padding-top: 0.8rem;
  border-top: 1px solid var(--line);
  font-style: italic;
}

@media (max-width: 620px) {
  .app-shell,
  .references {
    width: min(100% - 1rem, 760px);
  }

  .app-shell {
    margin-top: 1rem;
  }

  .form-grid,
  .result-links {
    grid-template-columns: minmax(0, 1fr);
  }

  .button-row .button {
    flex: 1 1 10rem;
  }

  .reading-line {
    grid-template-columns: 2.75rem minmax(0, 1fr);
    gap: 0.5rem;
    padding-inline: 0.55rem;
  }

  .ortolan-watermark {
    right: 10px;
    bottom: 10px;
    padding: 6px 9px;
  }

  .ortolan-watermark img {
    width: 78px;
  }
}

@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;
  }
}