/* ---------- Fonts: Poppins, self-hosted (src/fonts, SIL Open Font License) ---------- */
@font-face {
    font-family: 'Poppins';
    font-style: normal;
    font-weight: 300;
    font-display: swap;
    src: url('/fonts/poppins-300-latin-ext.woff2') format('woff2');
    unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
    font-family: 'Poppins';
    font-style: normal;
    font-weight: 300;
    font-display: swap;
    src: url('/fonts/poppins-300-latin.woff2') format('woff2');
    unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
    font-family: 'Poppins';
    font-style: normal;
    font-weight: 400;
    font-display: swap;
    src: url('/fonts/poppins-400-latin-ext.woff2') format('woff2');
    unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
    font-family: 'Poppins';
    font-style: normal;
    font-weight: 400;
    font-display: swap;
    src: url('/fonts/poppins-400-latin.woff2') format('woff2');
    unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
    font-family: 'Poppins';
    font-style: normal;
    font-weight: 500;
    font-display: swap;
    src: url('/fonts/poppins-500-latin-ext.woff2') format('woff2');
    unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
    font-family: 'Poppins';
    font-style: normal;
    font-weight: 500;
    font-display: swap;
    src: url('/fonts/poppins-500-latin.woff2') format('woff2');
    unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* sealevelmap.io
   Ported from the Squarespace site; type, colour and spacing were measured from
   the live pages on 2026-10-11. */

:root {
  --brand: #367fb9;
  --brand-dark: #2a6494;
  --ink: #15202b;
  --muted: #5a6875;
  --paper: #fff;
  --line: #e2e8ee;
  --font: "Poppins", -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --gutter: 6vw;
  --wrap: 760px;
}

@media (min-width: 1100px) { :root { --gutter: 5vw; } }

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 300 17px/1.7 var(--font);
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: var(--brand); text-underline-offset: .2em; }
h1, h2, h3 { margin: 0 0 .6em; font-weight: 500; line-height: 1.25; }
h1 { font-size: clamp(2rem, 1.4rem + 1.9vw, 2.9rem); }
h2 { font-size: clamp(1.5rem, 1.2rem + 1.1vw, 2.2rem); }
p { margin: 0 0 1.2em; }
[hidden] { display: none !important; }
:focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; }

.visually-hidden {
  position: absolute; width: 1px; height: 1px; margin: -1px; padding: 0;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip { position: absolute; top: .5rem; left: -9999px; z-index: 100; padding: .4rem .8rem; background: var(--paper); }
.skip:focus { left: var(--gutter); }
.wrap { max-width: var(--wrap); margin: 0 auto; }

/* ---------- Header ---------- */

.site-header {
  position: relative;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1.4rem var(--gutter);
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}
/* Over the homepage hero the header floats on the image. */
.site-header.is-transparent {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  background: none;
  border-bottom: 0;
  color: #fff;
}
.wordmark {
  font-size: 1.6rem;
  font-weight: 500;
  color: inherit;
  text-decoration: none;
  white-space: nowrap;
}
.site-header:not(.is-transparent) .wordmark { color: var(--ink); }
.site-nav ul { display: flex; gap: 2.2rem; margin: 0; padding: 0; list-style: none; }
.nav-links a { color: inherit; font-size: 1rem; text-decoration: none; }
.nav-links a:hover, .nav-links a[aria-current="page"] { text-decoration: underline; text-underline-offset: .35em; }
.menu-toggle { display: none; }

@media (max-width: 719px) {
  .js .menu-toggle {
    position: relative;
    z-index: 30;
    display: block;
    width: 44px;
    height: 32px;
    padding: 0;
    border: 0;
    background: none;
    color: inherit;
    cursor: pointer;
  }
  .menu-toggle span { position: absolute; left: 10px; right: 10px; height: 2px; background: currentColor; transition: transform .2s; }
  .menu-toggle span:first-child { top: 12px; }
  .menu-toggle span:last-child { top: 20px; }
  .menu-open .menu-toggle span:first-child { transform: translateY(4px) rotate(45deg); }
  .menu-open .menu-toggle span:last-child { transform: translateY(-4px) rotate(-45deg); }
  .menu-open .site-header { color: var(--ink); }

  .js .site-nav {
    position: fixed;
    inset: 0;
    z-index: 25;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--paper);
    color: var(--ink);
    opacity: 0;
    visibility: hidden;
    transition: opacity .2s, visibility .2s;
  }
  .menu-open .site-nav { opacity: 1; visibility: visible; }
  .js .site-nav ul { flex-direction: column; gap: 2rem; text-align: center; }
  .js .nav-links a { font-size: 1.6rem; }
  html:not(.js) .site-header { flex-wrap: wrap; }
  html:not(.js) .site-nav ul { gap: 1.2rem; }
}

/* ---------- Hero ---------- */

.hero {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 100vh;
  min-height: 100svh;
  padding: 8rem var(--gutter) 5rem;
  overflow: hidden;
  background: var(--brand);
  text-align: center;
  color: #fff;
}
.hero picture, .hero > img { position: absolute; inset: 0; }
.hero picture img, .hero > img { width: 100%; height: 100%; object-fit: cover; }
.hero::after { content: ""; position: absolute; inset: 0; background: rgba(54, 127, 185, .15); }
.hero-text { position: relative; z-index: 1; }
.hero h1 {
  margin-bottom: .8em;
  font-size: clamp(2.2rem, 1.2rem + 3.4vw, 3.6rem);
  font-weight: 300;
  text-shadow: 0 2px 24px rgba(0, 0, 0, .35);
}

.button {
  display: inline-block;
  padding: .85em 2.2em;
  border-radius: 300px;
  background: var(--paper);
  color: var(--brand);
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: .02em;
  text-decoration: none;
  transition: transform .15s ease, box-shadow .15s ease;
}
.button:hover { transform: translateY(-1px); box-shadow: 0 6px 20px rgba(0, 0, 0, .18); }

/* ---------- Sections ---------- */

.section { padding: clamp(3rem, 8vw, 6rem) var(--gutter); }
.section--page { padding-top: clamp(2.5rem, 5vw, 4rem); }
.section--page h1 { margin-bottom: .8em; }
.section figure { margin: 2.5rem 0; }
.section .chart-scroll { overflow-x: auto; }
.section .chart svg { display: block; width: 100%; min-width: 600px; height: auto; }
.section figcaption, .note { color: var(--muted); font-size: .92rem; line-height: 1.6; }
.note { padding-left: 1rem; border-left: 3px solid var(--line); }
.section ul { margin: 0 0 1.4em; padding-left: 1.2rem; }
.section li { margin-bottom: .7em; }
.section h2 { margin-top: 2em; }
.section h2:first-child { margin-top: 0; }

.band { background: var(--brand); }
.band img, .band picture { display: block; width: 100%; }

/* ---------- FAQ ---------- */

.faq { border-bottom: 1px solid var(--line); }
.faq summary {
  padding: 1.1em 2rem 1.1em 0;
  position: relative;
  font-size: 1.05rem;
  font-weight: 400;
  cursor: pointer;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  position: absolute;
  top: 1.55em;
  right: .35rem;
  width: 10px;
  height: 10px;
  border-right: 2px solid var(--brand);
  border-bottom: 2px solid var(--brand);
  transform: rotate(45deg);
  transition: transform .2s;
}
.faq[open] summary::after { transform: rotate(-135deg); }
.faq summary:hover { color: var(--brand); }
.faq-answer { padding-bottom: .6em; }
.faq-answer > :last-child { margin-bottom: 0; }

/* ---------- Signup ---------- */

.section--signup { background: #f4f8fb; text-align: center; }
.section--signup .wrap { max-width: 620px; }
.signup { display: flex; flex-wrap: wrap; gap: .75rem; justify-content: center; margin-top: 1.5rem; }
.signup input {
  flex: 1 1 260px;
  padding: .85em 1.2em;
  border: 1px solid var(--line);
  border-radius: 300px;
  font: inherit;
  background: var(--paper);
}
.signup button, .signup-fallback .button {
  padding: .85em 2.2em;
  border: 0;
  border-radius: 300px;
  background: var(--brand);
  color: #fff;
  font: 500 1rem var(--font);
  cursor: pointer;
}
.signup button:hover, .signup-fallback .button:hover { background: var(--brand-dark); }

/* ---------- Footer ---------- */

.site-footer {
  padding: clamp(2.5rem, 6vw, 4rem) var(--gutter);
  background: var(--ink);
  color: #c9d4de;
  font-size: .92rem;
  line-height: 1.8;
}
.footer-inner { max-width: var(--wrap); margin: 0 auto; }
.site-footer a { color: #fff; }
.site-footer p { margin: 0 0 1.1em; }
.footer-licence { margin-bottom: 0; color: #9aa9b6; font-size: .85rem; }
.footer-support { color: #d5dee6; }
.site-footer .support-link {
    display: inline-block; margin-left: .35em; padding: .25em .8em;
    border: 1px solid #fff; border-radius: 999px; white-space: nowrap;
}
.site-footer .support-link:hover { background: #fff; color: var(--brand-dark); }
.site-footer .social { display: flex; gap: 1.2rem; margin: 0 0 1.4em; padding: 0; list-style: none; }
.site-footer .social a { display: block; color: #fff; }
.site-footer .social svg { width: 20px; height: 20px; }