*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #000;
  --text: rgba(255, 255, 255, 0.85);
  --text-bright: #fff;
  --text-muted: rgba(255, 255, 255, 0.4);
  --font-size: calc(0.875em + 0.3vw);
  --font-size-small: 75%;
  --font-size-large: 130%;
  --font-size-xl: 175%;
  --line-height: calc(1.35em + 0.3vw);
  --spacing: 1em;
}

html {
  font-size: 16px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Inter", "Helvetica Neue", sans-serif;
  font-size: var(--font-size);
  font-weight: 400;
  line-height: var(--line-height);
  letter-spacing: -0.01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
  max-width: calc(49ch + 2 * var(--spacing));
  padding: 5em var(--spacing) 5em calc(var(--spacing) + 2.8ch);
  display: flex;
  flex-direction: column;
  gap: 1.8em;
}

h1 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--text-bright);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.lead {
  font-size: var(--font-size-large);
  line-height: 1.5;
  color: var(--text);
  max-width: 42ch;
}

.cta {
  display: inline-block;
  color: var(--text-bright);
  font-weight: 700;
  font-size: var(--font-size);
  text-decoration: underline;
  text-decoration-thickness: 0.085em;
  text-underline-offset: 0.15em;
  text-decoration-color: rgba(255, 255, 255, 0.4);
  letter-spacing: normal;
  margin-top: 0.4em;
}

.cta:hover {
  text-decoration-color: var(--text-bright);
}

.topics {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: 1.5em;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.topic {
  padding: 1.4em 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.topic h2 {
  font-size: 100%;
  font-weight: 700;
  color: var(--text-bright);
  margin-bottom: 0.3em;
}

.topic p {
  color: var(--text-muted);
  font-size: var(--font-size-small);
  letter-spacing: normal;
  line-height: 1.6;
}

footer {
  padding: 0 var(--spacing) 3em calc(var(--spacing) + 2.8ch);
  font-size: var(--font-size-small);
  color: var(--text-muted);
  letter-spacing: normal;
}

footer a {
  color: var(--text-muted);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-thickness: 0.085em;
  text-underline-offset: 0.15em;
  text-decoration-color: rgba(255, 255, 255, 0.15);
}

footer a:hover {
  color: var(--text-bright);
  text-decoration-color: var(--text-bright);
}