:root {
  --teal: #427b8d;
  --teal-dark: #19596e;
  --grey: #666;
  --line: rgba(102, 102, 102, 0.26);
  --width: 42rem;
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: #fff;
  color: var(--grey);
  font-family: 'IBM Plex Sans', sans-serif;
  font-weight: 300;
  text-align: center;
  -webkit-font-smoothing: antialiased;
}

h2, h3, p { margin: 0; }

h2 {
  font-size: 2.25rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--teal);
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--teal);
}

p { font-size: 1.25rem; line-height: 2; }

mark { background: transparent; color: var(--teal); }
mark.soft, .about mark { background: rgba(144, 144, 144, 0.25); color: inherit; }

a { color: var(--teal); }

/* Nav */
.nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.5rem 3rem;
  max-width: 100%;
  padding: 2rem;
  font-weight: 500;
}
.nav a { text-decoration: none; }
.nav a:hover { text-decoration: underline; color: #50c2e6; }

/* Layout */
.hero, .block, .footer {
  width: var(--width);
  max-width: 100%;
  margin: 0 auto;
  padding: 2rem;
}

.hero { padding-top: 3rem; padding-bottom: 4rem; }
.hero { display: flex; flex-direction: column; align-items: center; gap: 2rem; }
.logo { display: block; width: 29.75rem; max-width: 100%; height: auto; margin: 0 auto; }
.lead { color: var(--teal-dark); }

.band {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  padding: 6rem 2rem;
  background-image: linear-gradient(var(--overlay), var(--overlay)), var(--bg);
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
}
.band > p { max-width: var(--width); font-weight: 400; }
.band p.large { font-size: 1.375rem; }
.band--teal { --overlay: rgba(66, 123, 141, 0.69); }
.band--teal, .band--teal h2 { color: #fff; }
.band--yellow { --overlay: rgba(254, 237, 147, 0.69); }
.band--yellow, .band--yellow h2 { color: var(--teal-dark); }
.band--strong { --overlay: rgba(254, 237, 147, 0.81); }
.band--strong, .band--strong h2 { color: var(--teal); }

@media (hover: none) {
  .band { background-attachment: scroll; }
}

/* Buttons and icons */
.button {
  display: inline-block;
  min-width: 14.375rem;
  padding: 0 1rem;
  line-height: 2.5rem;
  border-radius: 0.375rem;
  background: var(--teal);
  color: #fff;
  font-weight: 500;
  text-decoration: none;
}
.button--wide { min-width: 17.125rem; }
.button:hover { background: var(--teal-dark); }

.chevron, .icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3.5rem;
  height: 3.5rem;
  border-radius: 50%;
  border: 1px solid var(--teal);
}
.chevron { border-color: var(--line); transition: border-color 0.25s; }
.chevron:hover { border-color: var(--teal); }
.band--teal .chevron { border-color: rgba(255, 255, 255, 0.46); }
.band--teal .chevron:hover { border-color: #fff; }
.chevron--teal { border-color: var(--teal) !important; }

.chevron svg, .icon svg { width: 60%; height: 60%; fill: var(--teal); }
.band--teal .chevron svg { fill: #fff; }

/* Sections */
.block { padding-top: 4rem; padding-bottom: 4rem; }
.block > * + * { margin-top: 2rem; }
.block > .chevron, .block > .button { margin-left: auto; margin-right: auto; }

.features {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 2.5rem 2rem;
}
.features { grid-template-columns: repeat(3, 1fr); }
.features li {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}
.features p { line-height: 1.5; }

.categories {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}
.category {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  padding: 2rem 1.5rem;
  border: 1px solid var(--line);
  border-radius: 0.75rem;
}
.block .category h3 { margin-top: 0; }
.tags {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem;
}
.tags li {
  padding: 0.25rem 0.875rem;
  border-radius: 999px;
  background: rgba(254, 237, 147, 0.6);
  color: var(--teal-dark);
  font-size: 1.0625rem;
  font-weight: 400;
  line-height: 1.75;
}

.summary { line-height: 1.5; }

.substack {
  display: block;
  width: 480px;
  max-width: 100%;
  height: 320px;
  margin: 0 auto;
  border: 1px solid #eee;
  background: #fff;
}
.archive { font-size: 1.125rem; font-weight: 500; }
.archive a { text-decoration: none; }
.archive a:hover { text-decoration: underline; }

hr { border: 0; height: 1px; background: var(--line); margin: 2.5rem 0; }

.block h3 { margin-top: 3rem; }
.cta-title { line-height: 1.625; }

.about h2 { color: var(--grey); font-weight: 300; }
.about p { font-size: 1.125rem; }
.about > * + * { margin-top: 1.5rem; }

/* Footer */
.footer { padding-top: 0; }
.footer hr { margin-top: 0; }
.social { display: flex; justify-content: center; gap: 1.25rem; }
.social svg { width: 1.5rem; height: 1.5rem; fill: rgba(102, 102, 102, 0.61); transition: fill 0.25s; }
.social a:hover svg { fill: var(--teal); }
.footer p { margin-top: 1rem; font-size: 0.875rem; color: rgba(102, 102, 102, 0.6); }

@media (max-width: 736px) {
  h2 { font-size: 1.875rem; }
  p { font-size: 1.125rem; }
  .nav { justify-content: center; gap: 0.5rem 1.5rem; padding: 1.5rem 1rem; }
  .hero, .block, .footer { padding-left: 1rem; padding-right: 1rem; }
  .band { padding: 4rem 1rem; min-height: auto; }
  .features { grid-template-columns: 1fr; }
  .categories { grid-template-columns: 1fr; }
}