* {
  box-sizing: border-box;
}

html {
  font-size: 16px;
}

body {
  margin: 0;
  background: #fff;
  color: #000;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 16px;
  line-height: 1.45;
}

main {
  min-height: 82vh;
  padding: 42px 44px 70px;
  display: flex;
  flex-direction: column;
}

header h1,
header p {
  margin: 0;
  font-weight: 400;
}

header h1 {
  font-size: 16px;
}

.practice {
  margin-top: 2px;
  margin-left: 48px;
}

footer {
  margin-top: auto;
  padding-top: 70px;
}

.about {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 48px;
  max-width: 920px;
  margin-bottom: 34px;
  align-items: start;
}

/* Keep the native hidden behaviour when the About section is closed. */
.about[hidden] {
  display: none;
}

.about-text {
  max-width: 600px;
}

.about p {
  margin: 0 0 22px;
}

.about p:last-child {
  margin-bottom: 0;
}

.about-image {
  width: 320px;
}

.about-image img {
  display: block;
  width: 100%;
  height: auto;
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
}

nav a,
.toggle {
  color: #000;
  font: inherit;
  line-height: inherit;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

.toggle {
  appearance: none;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

@media (max-width: 720px) {
  main {
    min-height: 78vh;
    padding: 28px 24px 48px;
  }

  .practice {
    margin-left: 46px;
  }

  footer {
    padding-top: 56px;
  }

  .about {
    grid-template-columns: 1fr;
    gap: 28px;
    margin-bottom: 30px;
  }

  .about-image {
    width: min(320px, 100%);
  }

  nav {
    gap: 18px;
  }
}