style.css

/* 345995 - bdazzled blue
   228CDB - tufts blue
   253031 - charleston green
   CFE8EF - columbia blue */

a {
  text-decoration: none;
}

* {
  margin: 0;
  padding: 0;

  box-sizing: border-box;
}

html {
  --bg-color: #cfe8ef;
  --primary-color: #228cdb;
  --primary-color-dark: #345995;
  --text-color: #00082f;
}

body.dark-blue {
  --bg-color: #00082f;
  --text-color: #ffffff;
}

body {
  background-color: var(--bg-color);

  color: var(--text-color);
  font-family: "Roboto", sans-serif;
}

.container {
  width: 300px;

  margin: 50px auto;

  text-align: center;
}

img {
  width: 100%;
}

img.avatar {
  width: 100px;
  height: 100px;
  padding: 3.7px;

  border: var(--primary-color) solid 4px;
  border-radius: 50%;
}

h1 {
  margin-bottom: 25px;

  font-size: 32px;
}

ul {
  list-style: none;
}

ul li a {
  width: 100%;
  height: 53px;
  margin-bottom: 16px;

  background-color: var(--primary-color);

  border-radius: 6px;

  color: white;
  text-transform: uppercase;
  font-size: 14px;

  display: flex;
  align-items: center;
  justify-content: center;

  transition: background-color 400ms;
}

/* pseudo-class */
ul li a:hover {
  background-color: var(--primary-color-dark);
  /* background-color: #364fc7; */
}