/* Cable Check — blueprint / technical direction (see docs/DESIGN.md).
   Navy drafting canvas, cyan schematic lines, amber annotation accents. */

:root {
  --bg: #0b1524;
  --surface-1: #122036;
  --surface-2: #182c49;
  --text: #e7f1ff;
  --text-muted: #8ea3c4;
  --accent: #4fd8e8;
  --accent-support: #ffb454;
  --success: #5be18a;
  --danger: #ff6b6b;

  --font-display: "Space Mono", ui-monospace, "SF Mono", monospace;
  --font-ui: "Inter", system-ui, -apple-system, sans-serif;

  --radius: 4px;
  --hair: rgba(79, 216, 232, 0.35);
  --hair-bright: rgba(79, 216, 232, 0.8);
  --glow: 0 0 24px rgba(79, 216, 232, 0.18);
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  min-height: 100dvh;
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.5;
  background-color: var(--bg);
  /* Blueprint grid + a soft radial lift so the canvas never reads as flat. */
  background-image:
    radial-gradient(120% 90% at 30% 12%, rgba(79, 216, 232, 0.09), transparent 60%),
    linear-gradient(rgba(79, 216, 232, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(79, 216, 232, 0.06) 1px, transparent 1px);
  background-size: 100% 100%, 32px 32px, 32px 32px;
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -48px;
  z-index: 20;
  padding: 8px 16px;
  border-radius: var(--radius);
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--hair-bright);
  text-decoration: none;
  transition: top 150ms var(--ease);
}
.skip-link:focus {
  top: 16px;
}

/* ---- layout ---------------------------------------------------------- */

.app {
  min-height: 100dvh;
  display: flex;
  align-items: stretch;
}

.stage {
  flex: 1;
  display: grid;
  grid-template-columns: 55% 45%;
  align-items: center;
  gap: 24px;
  width: min(1200px, 100%);
  margin: 0 auto;
  padding: 32px clamp(16px, 4vw, 56px);
}

.diagram-panel {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
}

.plug-diagram {
  width: 100%;
  height: auto;
  max-height: 78vh;
  filter: drop-shadow(0 0 18px rgba(79, 216, 232, 0.25));
}

.card-panel {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

/* ---- brand ----------------------------------------------------------- */

.brand {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.wordmark {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  letter-spacing: 0.06em;
  color: var(--text);
  text-transform: uppercase;
}
.wordmark-accent {
  color: var(--accent);
  text-shadow: 0 0 18px rgba(79, 216, 232, 0.5);
}

.tagline {
  margin: 0;
  max-width: 46ch;
  color: var(--text-muted);
  font-size: 0.98rem;
}

.noscript {
  margin: 0;
  padding: 16px 18px;
  max-width: 60ch;
  color: var(--text);
  background: var(--surface-1);
  border: 1px solid var(--accent-support);
  border-radius: var(--radius);
}

/* ---- question card --------------------------------------------------- */

.question-card {
  position: relative;
  padding: clamp(20px, 3vw, 32px);
  background:
    linear-gradient(180deg, var(--surface-1), var(--surface-2));
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  box-shadow: var(--glow), inset 0 1px 0 rgba(255, 255, 255, 0.04);
}
/* Corner ticks — a drafted, clipped-to-a-clipboard detail. */
.question-card::before,
.question-card::after {
  content: "";
  position: absolute;
  width: 12px;
  height: 12px;
  border: 1px solid var(--accent);
  opacity: 0.6;
}
.question-card::before {
  top: 8px;
  left: 8px;
  border-right: none;
  border-bottom: none;
}
.question-card::after {
  bottom: 8px;
  right: 8px;
  border-left: none;
  border-top: none;
}

.step-meta {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
}

.question-prompt {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.25rem, 2.6vw, 1.7rem);
  line-height: 1.25;
  color: var(--text);
}
.question-prompt:focus-visible {
  outline: none;
}

.options {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

/* ---- option buttons -------------------------------------------------- */

.option {
  width: 100%;
  min-height: 56px;
  padding: 14px 18px;
  text-align: left;
  font-family: var(--font-ui);
  font-size: 1.02rem;
  font-weight: 500;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  cursor: pointer;
  transition:
    transform 120ms var(--ease),
    border-color 150ms var(--ease),
    box-shadow 150ms var(--ease),
    background 150ms var(--ease);
}
.option::before {
  content: "›";
  margin-right: 12px;
  color: var(--accent);
  font-family: var(--font-display);
}
.option:hover {
  border-color: var(--hair-bright);
  background: #1d3457;
  box-shadow: 0 0 16px rgba(79, 216, 232, 0.16);
}
.option:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}
.option:active {
  transform: translateY(1px) scale(0.995);
  border-color: var(--accent);
  box-shadow: inset 0 0 12px rgba(79, 216, 232, 0.25);
}
.option:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.restart {
  margin-top: 24px;
  text-align: center;
  color: var(--bg);
  background: var(--accent);
  border-color: var(--accent);
  font-weight: 600;
}
.restart::before {
  content: "↺";
}
.restart:hover {
  background: #6fe6f4;
  box-shadow: 0 0 20px rgba(79, 216, 232, 0.4);
}

/* ---- verdict --------------------------------------------------------- */

.verdict-headline {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.3rem, 2.8vw, 1.8rem);
  line-height: 1.25;
}
.verdict-headline:focus-visible {
  outline: none;
}
.verdict-check {
  color: var(--accent);
}
.verdict-missing {
  color: var(--accent-support);
}
.verdict-conservative {
  color: var(--danger);
}
.verdict-any {
  color: var(--success);
}

.verdict-detail {
  margin: 0;
  max-width: 60ch;
  color: var(--text-muted);
  font-size: 1.02rem;
}

/* ---- mute toggle ----------------------------------------------------- */

.mute-toggle {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 15;
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  font-size: 1.1rem;
  color: var(--text);
  background: var(--surface-1);
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color 150ms var(--ease), box-shadow 150ms var(--ease);
}
.mute-toggle:hover {
  border-color: var(--hair-bright);
  box-shadow: var(--glow);
}
.mute-toggle:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ---- below-the-fold guide + FAQ -------------------------------------- */

.guide {
  border-top: 1px solid var(--hair);
  padding: clamp(40px, 6vw, 72px) clamp(16px, 4vw, 56px);
  background: linear-gradient(180deg, transparent, rgba(10, 18, 32, 0.55));
}

.guide-inner {
  max-width: 68ch;
  margin: 0 auto;
}

.guide-title {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.4rem, 3vw, 2rem);
  line-height: 1.2;
  color: var(--text);
}

.guide p {
  margin: 0 0 24px;
  color: var(--text-muted);
  font-size: 1.02rem;
}

.faq-q {
  margin: 32px 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
  line-height: 1.3;
  color: var(--accent);
}

.github-cta {
  display: inline-block;
  margin-top: 16px;
  padding: 14px 24px;
  min-height: 48px;
  font-weight: 600;
  color: var(--bg);
  background: var(--accent);
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  text-decoration: none;
  transition: box-shadow 150ms var(--ease), background 150ms var(--ease);
}
.github-cta:hover {
  background: #6fe6f4;
  box-shadow: 0 0 20px rgba(79, 216, 232, 0.4);
}
.github-cta:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ---- footer ---------------------------------------------------------- */

.site-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 24px;
  align-items: center;
  justify-content: center;
  padding: 32px 24px 48px;
  border-top: 1px solid var(--hair);
  font-size: 0.9rem;
}
.site-footer a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 150ms var(--ease);
}
.site-footer a:hover {
  color: var(--accent);
}
.site-footer a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: var(--radius);
}

/* ---- diagram callouts ------------------------------------------------ */

.callout-label {
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: 0.04em;
}
.callout-strong .callout-label {
  font-weight: 700;
  font-size: 15px;
}
.callout-strong circle {
  animation: pulse 1200ms var(--ease) 1;
}

@keyframes pulse {
  0% {
    transform: scale(1);
  }
  40% {
    transform: scale(1.8);
  }
  100% {
    transform: scale(1);
  }
}
.callout-strong circle {
  transform-box: fill-box;
  transform-origin: center;
}

/* ---- responsive ------------------------------------------------------ */

@media (max-width: 860px) {
  .stage {
    grid-template-columns: 1fr;
    align-content: center;
    gap: 16px;
    padding: 24px clamp(16px, 5vw, 32px);
  }
  .diagram-panel {
    min-height: 32vh;
    order: -1;
  }
  .plug-diagram {
    max-height: 34vh;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
  }
}