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

body,
h1,
h2,
p,
dl,
dd,
ul,
li {
  margin: 0;
  padding: 0;
}

/*
Color palette reference:
- Page background: #f5f7fb
- Header/card surface: #ffffff
- Main text: #172033
- Muted text / nav links: #667085
- Primary blue: #2563eb
- Primary blue hover: #1d4ed8
- Border: #d9e0ec
- Nav link hover background: #eef2ff
- Header shadow: rgb(23 32 51 / 0.08)
- Button shadow: rgb(37 99 235 / 0.24)
*/

:root {
  --background: #f5f7fb;
  --primary: #2563eb;
  --text: #172033;
  --muted: #667085;
}

body {
  padding: 16px;
  font-family: system-ui, sans-serif;
  background: var(--background);
  color: var(--text);
}

main {
  max-width: 60rem;
  margin-inline: auto;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  padding-block: 16px;
  padding-inline: 24px;
  gap: 16px;
  background: white;
  border: 1px solid #ddd;
  border-radius: 16px;
  margin-block: 64px;
  box-shadow: 0 0 32px rgb(23 32 51 / 0.08);
}

header a {
  color: inherit;
  text-decoration: none;
}

header > a:first-child {
  font-weight: 600;
  font-size: 1.125rem;
  color: var(--text);
}

header > nav > ul {
  list-style: none;
  display: flex;
  gap: 24px;
}

header > nav a {
  color: var(--muted);
}

header > a:last-child {
  background: var(--primary);
  font-weight: 600;
  color: white;
  padding: 12px 16px;
  border-radius: 999px;
  box-shadow: 0 8px 20px rgb(37 99 235 / 0.3);
}