html {
background: rgb(0,0,64);
background: linear-gradient(180deg, hsl(240, 100%, 13%) 0%, rgba(0,0,80,1) 100%);
background-attachment: fixed;
color:white;
font-family: Helvetica Neue,Helvetica,Arial,sans-serif; 
height: 100%
}

body {
margin: 0;
padding: 0;
height: 100%
}

button {
  display: block;
  margin: 25px auto;
  border: 1px solid lightblue;
  border-radius: 30px;
  width: 400px;
  height: 60px;
  cursor: pointer;
  background: #000050;
  background: linear-gradient(25deg, rgba(0, 0, 80, 1) 0%, rgba(80, 0, 180, 1) 100%);
  color: white;
  font-weight: bold;
}

button:hover {
  background: linear-gradient(25deg,rgba(60, 0, 130, 1) 0%, rgba(90, 0, 200, 1) 100%);
}

h3, h4, h5, h6 {
  margin: 0px;
  padding: 0px;
}

a {
  color: inherit;
  text-decoration: inherit;
}

.box {
  display: block;
  margin: 25px auto;
  padding: 25px;
  border: 1px solid lightblue;
  border-radius: 5px;
  width: 300px;
  height: auto;
  text-align: left;
}