body {
  margin: 0;
  font-family: "Segoe UI", Arial, sans-serif;
  color: #1f252b;
  background: #f7f7f4;
}

header {
  background: #20242a;
  color: white;
  padding: 24px 32px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 16px;
}

.brand img {
  flex: 0 0 auto;
  width: 64px;
  height: 64px;
}

header h1 {
  margin: 0;
  font-size: 30px;
}

header p {
  margin: 6px 0 0;
  color: #d9e2ea;
}

.layout {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: 28px;
  max-width: 1180px;
  margin: 0 auto;
  padding: 28px;
}

nav {
  border-right: 1px solid #d5dadd;
  padding-right: 20px;
}

nav a {
  display: block;
  color: #24394f;
  text-decoration: none;
  padding: 7px 0;
}

nav a:hover {
  text-decoration: underline;
}

main {
  max-width: 850px;
}

h1, h2, h3 {
  line-height: 1.2;
}

pre {
  overflow-x: auto;
  background: #1f252b;
  color: #f7f7f4;
  padding: 14px;
}

code {
  font-family: Consolas, "Liberation Mono", monospace;
}

table {
  border-collapse: collapse;
  width: 100%;
}

figure {
  margin: 18px 0 26px;
}

figure img {
  display: block;
  max-width: 100%;
  height: auto;
  border: 1px solid #d5dadd;
  background: #ffffff;
}

td, th {
  border: 1px solid #d5dadd;
  padding: 8px;
  text-align: left;
}

@media (max-width: 820px) {
  .layout {
    grid-template-columns: 1fr;
  }

  nav {
    border-right: 0;
    border-bottom: 1px solid #d5dadd;
    padding-bottom: 16px;
  }

  .brand {
    align-items: flex-start;
  }
}