/* Plumbmark: floating translucent panels over a drafting-grid background.
   Palette: six tokens defined on :root. Headings use a geometric stack; body text uses the system sans. */

:root {
  --c-bg: #e8ebfc;
  --c-panel: rgba(248, 249, 255, 0.78);
  --c-ink: #141a3a;
  --c-muted: #3d4672;
  --c-accent: #2e45b8;
  --c-line: #96a2e0;

  --font-heading: "Futura", "Avenir Next", "Century Gothic", sans-serif;
  --font-body: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  --gutter: 16px;
  --radius: 22px;
  --grid-step: 56px;
  --grid-line: color-mix(in srgb, var(--c-line) 45%, transparent);
  --panel-shadow: 0 30px 60px -40px color-mix(in srgb, var(--c-ink) 55%, transparent);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  font-family: var(--font-body);
  font-size: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  line-height: 1.65;
  color: var(--c-ink);
  background-color: var(--c-bg);
  background-image:
    linear-gradient(to right, var(--grid-line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-line) 1px, transparent 1px);
  background-size: var(--grid-step) var(--grid-step);
  background-attachment: fixed;
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
}

[hidden] {
  display: none !important;
}

/* Particle field: fixed behind everything, never takes pointer events */
.field {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 0;
  display: block;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.skip-link {
  position: fixed;
  top: -80px;
  left: var(--gutter);
  z-index: 20;
  padding: 10px 18px;
  border-radius: 999px;
  background-color: var(--c-ink);
  color: var(--c-bg);
  font-family: var(--font-heading);
  font-weight: 600;
  text-decoration: none;
}

.skip-link:focus {
  top: var(--gutter);
  outline: 3px solid var(--c-accent);
  outline-offset: 3px;
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.page {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 24px;
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--gutter);
}

@media (min-width: 720px) {
  .page {
    padding: 24px;
  }
}

/* Floating panels */
.panel {
  position: relative;
  background-color: var(--c-panel);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--panel-shadow);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  padding: clamp(20px, 3vw, 40px);
}

.float {
  animation: drift 10s ease-in-out infinite;
}

.float-slow {
  animation: drift 13s ease-in-out infinite;
  animation-delay: -6s;
}

@keyframes drift {
  0%,
  100% {
    transform: translate3d(0, 0, 0);
  }
  50% {
    transform: translate3d(0, -8px, 0);
  }
}

/* Header and navigation */
.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 20px;
  padding: 14px 18px;
}

@media (min-width: 720px) {
  .site-header {
    position: sticky;
    top: 12px;
    z-index: 5;
  }
}

.brand {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--c-ink);
  text-decoration: none;
}

.site-nav ul,
.footer-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav a,
.footer-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 6px 14px;
  border-radius: 999px;
  color: var(--c-ink);
  font-family: var(--font-heading);
  font-weight: 600;
  text-decoration: none;
}

.site-nav a:hover,
.footer-nav a:hover {
  background-color: var(--c-bg);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.site-nav a[aria-current="page"] {
  background-color: var(--c-ink);
  color: var(--c-bg);
}

.site-nav a[aria-current="page"]:hover {
  background-color: var(--c-accent);
  color: var(--c-bg);
}

.header-tools {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

main {
  display: grid;
  gap: 24px;
}

/* Typography */
h1,
h2,
h3 {
  margin: 0 0 0.55em;
  font-family: var(--font-heading);
  color: var(--c-ink);
  line-height: 1.12;
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(2.1rem, 1.4rem + 3vw, 3.6rem);
  font-weight: 700;
}

h2 {
  font-size: clamp(1.55rem, 1.2rem + 1.5vw, 2.25rem);
  font-weight: 600;
}

h3 {
  font-size: clamp(1.2rem, 1.05rem + 0.6vw, 1.45rem);
  font-weight: 600;
}

p {
  margin: 0 0 1em;
}

p:last-child {
  margin-bottom: 0;
}

.eyebrow {
  margin-bottom: 12px;
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--c-accent);
}

.lead {
  font-size: clamp(1.1rem, 1rem + 0.5vw, 1.3rem);
}

.muted {
  color: var(--c-muted);
}

a {
  color: var(--c-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  text-decoration-thickness: 2px;
}

:focus-visible {
  outline: 3px solid var(--c-accent);
  outline-offset: 3px;
}

/* Buttons (links styled as buttons) */
.button,
.button-quiet {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 22px;
  border: 2px solid var(--c-accent);
  border-radius: 999px;
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 180ms ease, color 180ms ease, border-color 180ms ease, transform 180ms ease;
}

.button {
  background-color: var(--c-accent);
  color: var(--c-bg);
}

.button-quiet {
  background-color: var(--c-panel);
  color: var(--c-accent);
}

.button:hover {
  background-color: var(--c-ink);
  border-color: var(--c-ink);
  color: var(--c-bg);
  transform: translateY(-2px);
}

.button-quiet:hover {
  background-color: var(--c-accent);
  color: var(--c-bg);
  transform: translateY(-2px);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

/* Hero and diagrams */
.hero {
  display: grid;
  gap: 28px;
  align-items: center;
}

.hero-art {
  margin: 0;
}

.hero-art figcaption {
  margin-top: 10px;
  font-size: 0.95rem;
}

.trail-art {
  display: block;
  width: 100%;
  height: auto;
}

.trail-art .plumb-line {
  stroke: var(--c-line);
  stroke-width: 2;
  stroke-dasharray: 3 6;
  stroke-linecap: round;
}

.trail-art .plumb-weight {
  fill: var(--c-accent);
}

.trail-art .trail-path {
  fill: none;
  stroke: var(--c-accent);
  stroke-width: 3;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.trail-art .trail-node {
  fill: var(--c-panel);
  stroke: var(--c-accent);
  stroke-width: 3;
}

.trail-art .trail-node-solid {
  fill: var(--c-accent);
}

.trail-art .trail-label {
  fill: var(--c-ink);
  font-family: var(--font-heading);
  font-size: 16px;
  font-weight: 600;
}

.trail-art .trail-note {
  fill: var(--c-muted);
  font-family: var(--font-body);
  font-size: 12px;
}

/* Layout blocks */
.split {
  display: grid;
  gap: 24px;
}

.ruled {
  display: grid;
  margin: 0;
  padding: 0;
  list-style: none;
}

.ruled > li {
  padding: 18px 0;
  border-top: 1px solid var(--c-line);
}

.ruled > li:first-child {
  padding-top: 0;
  border-top: 0;
}

.grid-3 {
  display: grid;
  gap: 16px;
}

.tile {
  padding: 22px;
  border: 1px solid var(--c-line);
  border-radius: 16px;
  background-color: color-mix(in srgb, var(--c-bg) 70%, var(--c-panel));
}

.stages {
  display: grid;
  gap: 20px;
}

.questions {
  margin: 0;
  padding-left: 1.2em;
}

.questions li::marker {
  color: var(--c-accent);
}

.records {
  display: grid;
  gap: 20px;
}

.record-facts {
  margin: 0;
}

.record-facts dt {
  margin-top: 12px;
  font-family: var(--font-heading);
  font-weight: 600;
  color: var(--c-accent);
}

.record-facts dt:first-child {
  margin-top: 0;
}

.record-facts dd {
  margin: 2px 0 0;
}

.note {
  margin: 0;
  padding-left: 16px;
  border-left: 3px solid var(--c-accent);
  color: var(--c-muted);
  font-size: 0.95rem;
}

.mail-panel {
  display: grid;
  gap: 16px;
  justify-items: start;
}

.mail-address {
  font-family: var(--font-heading);
  font-size: clamp(1.2rem, 1rem + 1vw, 1.6rem);
  font-weight: 600;
  overflow-wrap: anywhere;
}

.site-footer {
  display: grid;
  gap: 16px;
  font-size: 0.95rem;
}

.site-footer p {
  margin: 0;
}

@media (min-width: 760px) {
  .hero {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    padding: clamp(28px, 4vw, 56px);
  }

  .split {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: start;
  }

  .grid-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .records {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .offset {
    margin-top: 48px;
  }
}

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

  .float,
  .float-slow {
    animation: none;
  }

  .button:hover,
  .button-quiet:hover {
    transform: none;
  }

  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
    scroll-behavior: auto !important;
  }
}

/* Inner two-column block used inside a panel (method page intro) */
.hero-split {
  display: grid;
  gap: 28px;
  align-items: center;
}

@media (min-width: 760px) {
  .hero-split {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
  }
}