style.css

* {
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: "Inter", sans-serif;
}

body {
  background-color: #61d165;
  text-align: center;
  font-weight: 500;
  color: #000;
}

section {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
  -ms-flex-direction: column;
  flex-direction: column;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  width: 100%;
  height: 100vh;
}

.hex-code {
  font-size: 100px;
  font-weight: 500;
  margin: 10px 0;
  cursor: pointer;
  border: none;
  background: transparent;
}

.hex-code:hover {
  background: transparent;
}

.guiding-texts {
  padding: 20px;
  margin-bottom: 10px;
  background: rgba(255, 255, 255, 0.4);
}

button {
  width: 480px;
  padding: 18px;
  margin-top: 20px;
  background-color: #fff;
  font-size: 16px;
  font-weight: 600;
  border: 2px solid #000;
  border-radius: 5px;
  cursor: pointer;
}

button:hover {
  background-color: rgb(233, 233, 233);
}