body {
    margin: 0;
    font-family: Arial, sans-serif;
    background-color: #555555;
    color: white;
}

header {
    text-align: center;
    padding: 20px;
}

.logo {
    max-width: 120px;
}

.welcome {
    text-align: center;
    padding: 40px 20px;
}

.bottom-nav {
  position: fixed;
  bottom: 0;
  width: 100%;
  background-color: #222;
  display: flex;
  justify-content: space-around;
  padding: 10px 0;
  z-index: 1000;
}
  /* края на .bottom-nav, това е твоят ред 31 */

  /* <<< ТУК ВМЪКВАШ НОВИТЕ ДВА СЕЛЕКТОРА */
.bottom-nav a:link,
.bottom-nav a:visited {
  color: white;
  text-decoration: none;
}

/* сегашната ти дефиниция започва на ред 33 */
.bottom-nav a {
  display: flex;
  flex-direction: column;
  align-items: center;
  color: white;
  text-decoration: none;
  font-size: 12px;
}

.bottom-nav a.active {
  color: white;
  font-weight: bold;
  transition: color 0.3s ease;
}

.bottom-nav a:hover {
  color: #ccc;
}

.bottom-nav img {
  width: 24px;
  height: 24px;
  object-fit: contain;
}

.nav-label {
  margin-top: 4px;
  line-height: 1;
}