/* =========================================================
   Lodestone Labs — design tokens
   Ink        #14181C   background
   Slate      #232B31   panel / alt background
   Teal       #2F5D62   survey-map accent
   Rust       #A85C32   oxidised core accent
   Amber      #C9A227   uncertainty-band accent
   Grey-blue  #4A5560   muted structural tone
   Limestone  #E8E2D4   text on dark
   ========================================================= */

:root {
  --ink: #14181C;
  --slate: #232B31;
  --teal: #2F5D62;
  --rust: #A85C32;
  --amber: #C9A227;
  --greyblue: #4A5560;
  --limestone: #E8E2D4;

  --display: "Archivo Expanded", sans-serif;
  --body: "IBM Plex Sans", sans-serif;
  --mono: "IBM Plex Mono", monospace;

  --wrap: 1120px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--ink);
  color: var(--limestone);
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 28px;
}

h1, h2, h3 {
  font-family: var(--display);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 0.5em;
  color: var(--limestone);
}

h1 { font-size: clamp(2.6rem, 5vw, 4.2rem); line-height: 1.02; font-weight: 800; }
h2 { font-size: clamp(1.7rem, 3vw, 2.4rem); line-height: 1.15; }
h3 { font-size: 1.15rem; font-family: var(--body); font-weight: 600; }

p { margin: 0 0 1em; }

a { color: inherit; }

.eyebrow {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 0.9em;
}

.lede {
  font-size: 1.08rem;
  color: rgba(232, 226, 212, 0.82);
  max-width: 640px;
}

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(10px);
  background: rgba(20, 24, 28, 0.72);
  border-bottom: 1px solid rgba(232, 226, 212, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.logo {
  font-family: var(--display);
  font-weight: 800;
  letter-spacing: 0.06em;
  font-size: 1.05rem;
  text-decoration: none;
  color: var(--limestone);
}

.nav {
  display: flex;
  gap: 32px;
}

.nav a {
  text-decoration: none;
  font-size: 0.95rem;
  color: rgba(232, 226, 212, 0.75);
  transition: color 0.15s ease;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 34px;
  height: 34px;
  background: none;
  border: none;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--limestone);
}

/* ---------- buttons ---------- */
.btn {
  display: inline-block;
  padding: 0.85em 1.6em;
  border-radius: 3px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  transition: transform 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.btn-primary {
  background: var(--amber);
  color: var(--ink);
}
.btn-primary:hover { transform: translateY(-1px); background: #dcb236; }

.btn-ghost {
  border: 1px solid rgba(232, 226, 212, 0.35);
  color: var(--limestone);
  margin-left: 14px;
}
.btn-ghost:hover { border-color: var(--amber); color: var(--amber); }

.btn-large { font-size: 1.05rem; padding: 1em 2em; }

/* ---------- hero ---------- */
.hero { padding: 84px 0 100px; }

.hero-inner {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}

.hero-sub {
  font-size: 1.08rem;
  color: rgba(232, 226, 212, 0.82);
  max-width: 480px;
}

.hero-cta { margin-top: 1.6em; }

.hero-art { text-align: center; }

.strata-svg {
  width: 100%;
  max-width: 340px;
  border-radius: 6px;
  box-shadow: 0 30px 60px -20px rgba(0,0,0,0.6);
}

.art-caption {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: rgba(232, 226, 212, 0.45);
  margin-top: 0.9em;
  letter-spacing: 0.02em;
}

/* ---------- problem ---------- */
.problem {
  padding: 88px 0;
  background: var(--slate);
  border-top: 1px solid rgba(232, 226, 212, 0.06);
  border-bottom: 1px solid rgba(232, 226, 212, 0.06);
}

/* ---------- approach ---------- */
.approach { padding: 100px 0; }

.core-log {
  margin-top: 48px;
  border-left: 1px solid rgba(232, 226, 212, 0.15);
}

.core-entry {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 32px;
  padding: 32px 0 32px 32px;
  position: relative;
  border-bottom: 1px solid rgba(232, 226, 212, 0.08);
}

.core-entry:last-child { border-bottom: none; }

.core-entry::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 40px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--tag, var(--amber));
}

.core-tag {
  font-family: var(--mono);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--tag, var(--amber));
  padding-top: 2px;
}

.core-text p { color: rgba(232, 226, 212, 0.78); max-width: 560px; }

/* ---------- why ---------- */
.why {
  padding: 100px 0;
  background: var(--slate);
  border-top: 1px solid rgba(232, 226, 212, 0.06);
}

.why-inner {
  display: grid;
  grid-template-columns: 1fr 0.9fr;
  gap: 56px;
  align-items: center;
}

.band-svg { width: 100%; max-width: 400px; }

.band-label {
  font-family: var(--mono);
  font-size: 11px;
  fill: rgba(232, 226, 212, 0.6);
}

/* ---------- contact ---------- */
.contact { padding: 110px 0 130px; text-align: center; }

.contact-inner {
  max-width: 620px;
  margin: 0 auto;
}

.contact .lede { margin-left: auto; margin-right: auto; }

.contact-form {
  text-align: left;
  max-width: 480px;
  margin: 0 auto;
  display: grid;
  gap: 20px;
}

.hp-field {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.form-row {
  display: grid;
  gap: 6px;
}

.form-row label {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: rgba(232, 226, 212, 0.6);
}

.form-row .optional {
  text-transform: none;
  letter-spacing: 0;
  color: rgba(232, 226, 212, 0.35);
}

.form-row input,
.form-row textarea {
  font-family: var(--body);
  font-size: 1rem;
  color: var(--limestone);
  background: rgba(232, 226, 212, 0.05);
  border: 1px solid rgba(232, 226, 212, 0.2);
  border-radius: 3px;
  padding: 0.75em 0.9em;
  resize: vertical;
}

.form-row input:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--amber);
  background: rgba(232, 226, 212, 0.08);
}

.contact-form .btn { justify-self: start; }

[data-fs-success],
[data-fs-error] {
  font-family: var(--mono);
  font-size: 0.85rem;
  padding: 0.7em 0.9em;
  border-radius: 3px;
  display: none;
}

[data-fs-success][data-fs-active] {
  display: block;
  color: var(--ink);
  background: var(--amber);
}

[data-fs-error][data-fs-active] {
  display: block;
  color: var(--limestone);
  background: rgba(168, 92, 50, 0.25);
  border: 1px solid var(--rust);
}

/* per-field error text (small, inline under each input) */
.form-row [data-fs-error] {
  display: block;
  padding: 0;
  background: none;
  border: none;
  font-size: 0.78rem;
  color: var(--rust);
  min-height: 1.2em;
}

.form-row input[aria-invalid="true"],
.form-row textarea[aria-invalid="true"] {
  border-color: var(--rust);
}

.contact-fallback {
  margin-top: 28px;
  font-size: 0.9rem;
  color: rgba(232, 226, 212, 0.55);
}

.contact-fallback a {
  color: var(--limestone);
  text-decoration: underline;
  text-decoration-color: rgba(232, 226, 212, 0.35);
}
.contact-fallback a:hover { color: var(--amber); }

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid rgba(232, 226, 212, 0.08);
  padding: 28px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.85rem;
  color: rgba(232, 226, 212, 0.55);
}

.footer-nav { display: flex; gap: 24px; }
.footer-nav a { text-decoration: none; color: inherit; }
.footer-nav a:hover { color: var(--amber); }

/* ---------- reveal-on-scroll ---------- */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- responsive ---------- */
@media (max-width: 860px) {
  .hero-inner, .why-inner { grid-template-columns: 1fr; }
  .hero-art { order: -1; max-width: 280px; margin: 0 auto 12px; }

  .nav {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: var(--ink);
    flex-direction: column;
    gap: 0;
    max-height: 0;
    overflow: hidden;
    border-bottom: 1px solid rgba(232, 226, 212, 0.08);
    transition: max-height 0.25s ease;
  }
  .nav.is-open { max-height: 220px; }
  .nav a { padding: 16px 28px; border-top: 1px solid rgba(232, 226, 212, 0.06); }
  .nav-toggle { display: flex; }

  .core-entry { grid-template-columns: 1fr; gap: 8px; }
  .logo { font-size: 0.85rem; letter-spacing: 0.04em; }
}

@media (max-width: 480px) {
  .btn-ghost { margin-left: 0; display: block; margin-top: 12px; width: fit-content; }
}