/* ==========================================================================
   Overtone Photonics — shared stylesheet
   Edit colours, fonts and spacing here; changes apply to every page.
   ========================================================================== */

:root {
  --blue:        #185FA5;   /* primary — from logo outer wave */
  --terracotta:  #C1614A;   /* accent  — from logo inner wave */
  --ink:         #1a1a1a;   /* body text */
  --ink-soft:    #55606b;   /* secondary text */
  --paper:       #F7F8F9;   /* page background */
  --rule:        #E8ECF0;   /* dividers, borders */

  --measure:     34rem;     /* comfortable reading width */
  --gutter:      1.5rem;
}

/* --- reset ------------------------------------------------------------- */

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

body, h1, h2, h3, p, ul, figure {
  margin: 0;
  padding: 0;
}

/* --- base -------------------------------------------------------------- */

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

body {
  background: var(--paper);
  color: var(--ink);
  font-family: Georgia, "Iowan Old Style", "Times New Roman", serif;
  font-size: 1.0625rem;
  line-height: 1.65;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.wrap {
  width: 100%;
  max-width: 58rem;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* --- header & navigation ----------------------------------------------- */

.masthead {
  border-bottom: 1px solid var(--rule);
  background: #fff;
  position: relative;
  overflow: hidden;
}

/* the logo motif, oversized and faint, as a background signature */
.masthead__motif {
  position: absolute;
  right: -5rem;
  top: 50%;
  transform: translateY(-50%);
  width: 22rem;
  height: 22rem;
  opacity: 0.05;
  pointer-events: none;
}

.masthead .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem 2rem;
  padding-block: 1.25rem;
  position: relative;   /* sit above the motif */
  z-index: 1;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: inherit;
}

.brand__mark { width: 2.5rem; height: 2.5rem; flex: none; }

.brand__name {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-weight: 600;
  font-size: 1.0625rem;
  letter-spacing: 0.01em;
  line-height: 1.2;
}

.brand__name span {
  display: block;
  font-weight: 400;
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-top: 0.15rem;
}

/* nav bar across the top */
.nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 1.75rem;
}

.nav a {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 0.8125rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--ink-soft);
  padding-block: 0.35rem;
  border-bottom: 2px solid transparent;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.nav a:hover,
.nav a:focus-visible { color: var(--blue); }

.nav a[aria-current="page"] {
  color: var(--ink);
  border-bottom-color: var(--terracotta);
}

/* --- main content ------------------------------------------------------ */

main { flex: 1 0 auto; padding-block: 4rem 5rem; }

.eyebrow {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--terracotta);
  margin-bottom: 1rem;
}

h1 {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-weight: 600;
  font-size: clamp(1.75rem, 1.2rem + 2.2vw, 2.75rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  max-width: 22ch;
  margin-bottom: 1.75rem;
}

h2 {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-weight: 600;
  font-size: 1.125rem;
  letter-spacing: 0.01em;
  margin-top: 2.75rem;
  margin-bottom: 0.75rem;
}

p { max-width: var(--measure); }
p + p { margin-top: 1.15rem; }

.lede {
  font-size: 1.25rem;
  line-height: 1.55;
  color: var(--ink);
}

a { color: var(--blue); }
a:hover { color: var(--terracotta); }

.rule {
  border: 0;
  border-top: 1px solid var(--rule);
  margin-block: 3rem;
  max-width: var(--measure);
}

/* definition-style contact list */
.details {
  max-width: var(--measure);
  margin-top: 2rem;
}

.details div {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  padding-block: 0.85rem;
  border-top: 1px solid var(--rule);
}

.details dt {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-soft);
  flex: 0 0 8rem;
  padding-top: 0.25rem;
}

.details dd { margin: 0; }

/* holding note for pages not yet written */
.holding {
  max-width: var(--measure);
  border-left: 2px solid var(--terracotta);
  padding-left: 1.25rem;
  color: var(--ink-soft);
}

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

.colophon {
  border-top: 1px solid var(--rule);
  background: #fff;
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 0.8125rem;
  color: var(--ink-soft);
}

.colophon .wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 2rem;
  justify-content: space-between;
  padding-block: 1.5rem;
}

/* --- accessibility ------------------------------------------------------ */

:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
}

/* --- small screens ------------------------------------------------------ */

@media (max-width: 34rem) {
  .masthead .wrap { padding-block: 1rem; }
  .nav ul { gap: 1.15rem; }
  .masthead__motif { display: none; }
  main { padding-block: 2.75rem 3.5rem; }
  .details dt { flex-basis: 100%; }
}