* {box-sizing: border-box}


body, html {
  margin: 0;
 
}
  h1{
  background-color: #87ceeb;
  align-content: center;
  text-align: center;
  margin-bottom: 0.2rem;
  margin-top: 0.5rem;
}

.responsive-two-column-grid {
    display:block;
    float: center;
    margin-top: 0;
    margin-bottom: 0;
}

.responsive-two-column-grid > * {
    padding:1rem;
    margin: 0.2rem;
    background-color: silver;
    margin-bottom: 0;
}

@media (min-width:768px) {
    .responsive-two-column-grid {
        display: grid;
        grid-template-columns: .35fr .75fr;
    }
} 

.responsive-three-column-grid {
    display:block;
    float: center;
    margin-top: 0;
    margin-bottom: 0;
}

.responsive-three-column-grid > * {
    padding:.1rem 1rem;
    margin: 0.2rem;
    background-color: silver;
    margin-bottom: 0;
}


@media (min-width:768px) {
    .responsive-three-column-grid {
        display: grid;
        grid-auto-rows: 1fr;
        grid-template-columns: 1fr 1fr 1fr;
    }
}

.tablink {
  background-color: gray;
  color: black;
  float: left;
  border: none;
  outline: none;
  cursor: pointer;
  padding: 12px 12px;
  font-size: 15px;
  width: 25%;
  margin-top: 0.5rem;
  margin-bottom: 0.1rem;
}

.tablink:hover {
  background-color: skyblue;
}

.tabcontent {
  /*color: white;*/
  display: none;
  padding: 70px 20px 18px 20px;
}

.next{
    background-color: #04AA6D;
    color: white;
    font-size: 18px;
    margin-top: 0.5rem;
    align-content: center;
    text-align: center;
    padding: 8px 16px;
    text-decoration: none;
    width:8rem;
    float:right;
}
.next:hover {
  background-color: #ada;
  color: black;
}
.previous{
    display: block;
    float:left;
    background-color: #04AA6D;
    color: white;
    font-size: 18px;
    margin-top: 0.5rem;
    align-content: center;
    text-align: center;
    padding: 8px 16px;
    text-decoration: none;
    width:8rem;
}
.previous:hover {
  background-color: #ada;
  color: black;
}
input{
    background-color:mediumturquoise;
    align-content: center;
    text-align: center;
    font-style:bold italic;
    font-size: 14px;
    color:black;
    border:.5px solid black;
    color: black;
}
input:hover{
    background-color: darkcyan;
    color:white;
}
.vectorspace{
  display: block;
  background-color: #e8f5e9;
  border: 2px solid darkgreen;
  padding: 1rem;
  margin: 80px 10px;
  
a{
  text-decoration: none;
  color:white;
}
input{
  cursor:pointer;
}