/* Perenna website. Brand: Perenna design system v1.1 (light, paper first).
   Type: Mona Sans and Mona Sans Mono (SIL Open Font License 1.1, Copyright 2022 The Mona Sans
   Project Authors). The files in /fonts are Latin subsets, renamed Perenna Sans and Perenna Mono
   because the licence reserves the name "Mona" for unmodified fonts. */

@font-face {
  font-family: "Perenna Sans";
  src: url("fonts/perenna-sans.woff2") format("woff2");
  font-weight: 400 700;
  font-stretch: 100% 125%;
  font-display: swap;
}

@font-face {
  font-family: "Perenna Mono";
  src: url("fonts/perenna-mono.woff2") format("woff2");
  font-weight: 400 600;
  font-display: swap;
}

:root {
  color-scheme: light;

  --bg: #ffffff;
  --bg-panel: #f4f6f8;
  --text: #0e1116;
  --text-body: #3a4047;
  --text-lead: #50565d;
  --text-muted: #666d74;
  --text-faint: #80878e;
  --border: #d7dbe0;

  --accent: #007798;
  --accent-hover: #025972;
  --block: #007798;
  --block-on: #ffffff;
  --block-soft: #e0f5fe;
  --rule-strong: #22c3f5;
  --focus: #22c3f5;
  --ink-hover: #262c32;

  --font-sans: "Perenna Sans", "Mona Sans", Inter, system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  --font-mono: "Perenna Mono", "Mona Sans Mono", ui-monospace, Menlo, Consolas, monospace;

  --maxw: 1280px;
  --margin: 32px;
  --header-h: 72px;
}

@media (max-width: 760px) {
  :root {
    --margin: 20px;
    --header-h: 64px;
  }
}

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

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text-body);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.55;
  font-weight: 400;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  color: var(--accent-hover);
}

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

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

.label {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.45;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

.nb {
  white-space: nowrap;
}

/* Header */

.site-header {
  border-bottom: 1px solid var(--border);
}

.site-header .wrap {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: block;
  padding: 9px 0;
}

.brand svg {
  height: 18px;
  width: auto;
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
  font-size: 15px;
  font-weight: 500;
}

.nav a {
  color: var(--text-body);
}

.nav a:hover {
  color: var(--accent);
}

@media (max-width: 760px) {
  .brand svg {
    height: 15px;
  }

  .nav .wide-only {
    display: none;
  }
}

/* Hero */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  padding-left: max(var(--margin), calc((100% - var(--maxw)) / 2 + var(--margin)));
  min-height: min(740px, calc(100svh - var(--header-h)));
}

.hero-copy {
  align-self: center;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 24px;
  max-width: 740px;
  padding: 96px 56px 104px 0;
}

.hero h1 {
  font-size: clamp(2.5rem, 1.1rem + 4.2vw, 4.75rem);
  line-height: 1.02;
  font-weight: 700;
  letter-spacing: -0.012em;
  color: var(--text);
  text-wrap: balance;
}

.lead {
  font-size: clamp(1.0625rem, 0.95rem + 0.45vw, 1.25rem);
  line-height: 1.5;
  color: var(--text-lead);
  max-width: 34em;
}

.actions {
  padding-top: 8px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: var(--text);
  color: #ffffff;
  font-size: 16px;
  font-weight: 500;
  line-height: 1;
  padding: 17px 22px;
  border-radius: 4px;
}

.btn:hover {
  background: var(--ink-hover);
  color: #ffffff;
}

.btn svg {
  width: 16px;
  height: 16px;
}

.hero-panel {
  position: relative;
  min-height: 440px;
  overflow: hidden;
}

.hero-panel svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  max-width: none;
}

@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
    padding-left: 0;
    min-height: 0;
  }

  .hero-copy {
    max-width: none;
    padding: 48px var(--margin) 56px;
  }

  .hero-panel {
    min-height: 0;
    height: 208px;
  }
}

/* Sections */

.section {
  padding: clamp(72px, 9vw, 128px) 0;
}

.section + .section {
  padding-top: 0;
}

.axis {
  height: 1px;
  margin-bottom: clamp(56px, 7vw, 96px);
  background: repeating-linear-gradient(
    90deg,
    var(--text-faint) 0 14px,
    transparent 14px 18px,
    var(--text-faint) 18px 20px,
    transparent 20px 24px
  );
}

.section-head {
  display: flex;
  flex-direction: column;
  gap: 20px;
  max-width: 780px;
}

.section h2 {
  font-size: clamp(1.875rem, 1.15rem + 2.3vw, 3rem);
  line-height: 1.08;
  font-weight: 600;
  font-stretch: 112%;
  letter-spacing: -0.01em;
  color: var(--text);
  text-wrap: balance;
}

.section-head .intro {
  font-size: 18px;
  line-height: 1.55;
  max-width: 40em;
}

@media (min-width: 1000px) {
  .section-head {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 24px;
    max-width: none;
  }

  .section-head .label {
    grid-column: 1 / -1;
  }

  .section-head h2 {
    grid-column: 1 / span 6;
    max-width: 15em;
  }

  .section-head .intro {
    grid-column: 8 / span 5;
    padding-top: 0.35em;
  }
}

/* The methane block: the one panel on the page that carries the point */

.block {
  margin-top: 56px;
  background: var(--block);
  color: var(--block-on);
  border-radius: 12px;
  padding: clamp(28px, 4.5vw, 56px);
}

/* Three-column rows with the bright methane rule */

.cols {
  margin-top: 64px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 40px 32px;
}

.col {
  border-top: 2px solid var(--rule-strong);
  padding-top: 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.col p {
  font-size: 17px;
  line-height: 1.55;
}

@media (max-width: 900px) {
  .cols {
    grid-template-columns: 1fr;
    gap: 36px;
  }
}

/* The audit steps sit on the methane block, in white */

.block--steps .cols {
  margin-top: 0;
}

.block--steps .col {
  border-top: 0;
  padding-top: 0;
}

.block--steps .label {
  color: var(--block-soft);
}

.block--steps .col p {
  font-size: 18px;
  line-height: 1.5;
  color: var(--block-on);
}

/* Process drawing */

.drawing {
  margin-top: 56px;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: clamp(20px, 3vw, 40px) clamp(12px, 2.5vw, 32px);
}

.drawing figcaption {
  margin-bottom: 20px;
  color: var(--text-muted);
}

.drawing text {
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
}

.drawing--tall {
  display: none;
  width: 100%;
  max-width: 440px;
  margin: 0 auto;
}

@media (max-width: 1099px) {
  .drawing--wide {
    display: none;
  }

  .drawing--tall {
    display: block;
  }
}

/* Contact */

.contact-row {
  margin-top: 40px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 24px 40px;
}

.contact-mail {
  font-size: clamp(1.5rem, 1rem + 2vw, 2.5rem);
  line-height: 1.15;
  font-weight: 600;
  font-stretch: 106%;
  letter-spacing: -0.005em;
  overflow-wrap: anywhere;
}

.btn-quiet {
  font: inherit;
  font-size: 15px;
  font-weight: 500;
  line-height: 1;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 13px 16px;
  cursor: pointer;
}

.btn-quiet:hover {
  border-color: var(--text);
}

.btn-quiet[hidden] {
  display: none;
}

/* Footer */

.site-footer .wrap {
  padding-top: 0;
  padding-bottom: 40px;
}

.site-footer .axis {
  margin-bottom: 32px;
}

.footer-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px 32px;
}

.footer-row .brand svg {
  height: 15px;
}

.footer-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 28px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.footer-meta a {
  color: var(--text-muted);
}

.footer-meta a:hover {
  color: var(--accent);
}

/* Not-found page */

.notfound {
  min-height: calc(100svh - var(--header-h) - 140px);
  display: flex;
  align-items: center;
}

.notfound .wrap {
  width: 100%;
}

.notfound .section-head {
  padding: 96px 0;
}

.notfound-title {
  font-size: clamp(1.875rem, 1.15rem + 2.3vw, 3rem);
  line-height: 1.08;
  font-weight: 600;
  font-stretch: 112%;
  letter-spacing: -0.01em;
  color: var(--text);
}

@media (min-width: 1000px) {
  .notfound .section-head h1 {
    grid-column: 1 / span 8;
  }

  .notfound .section-head .intro {
    grid-column: 1 / span 8;
    padding-top: 0;
  }
}