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

body {
  margin: 0;
  background-color: black;
  color: white;
  font-family: "Inter";
  font-weight: 300;
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
}

header h1 {
  font-size: 1.5rem;
  font-weight: 300;
  margin: 0;
  transition: filter 0.5s ease;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 3rem;
  margin: 0;
  margin-right: 2rem;
  padding: 0;
}

nav a {
  text-decoration: none;
  color: white;
  font-size: 1.2rem;
  transition: color 0.3s ease;
}

nav a:hover,
nav a:focus {
  color: lightblue;
  outline: none;
}

/* Main section: */

main {
  max-width: 80%;
  margin: 0rem 5rem;
}

h2 {
  font-size: 3rem;
  font-weight: 800;
  padding-bottom: 0;
  margin-bottom: 0;
}

h3 {
  margin: 0;
}

main li a {
  color: lightblue;
  text-decoration: none;
}

main li a:hover {
  text-decoration: underline;
}

img {
  width: 50%;
  border-radius: 5px;
  filter: grayscale(100%);
  transition: filter 0.5s ease;
  display: block;
  margin: 0 auto;
}

img:hover {
  filter: grayscale(0%);
}

#center {
  text-align: center;
}

/* Footer: */

footer {
  padding: 1.5rem 2rem;
  text-align: center;
  font-size: 0.9rem;
  color: #777;
  border-top: 1px solid #222;
}

footer a {
  color: #777;
  text-decoration: underline;
}

footer a:hover,
footer a:focus {
  color: lightblue;
  outline: none;
}

/* Small screens: */
@media (max-width: 700px) {
  nav ul {
    display: none;
  }
}