*{
    box-sizing: border-box;
}

html {
  width: 100%;
  height: 100%;
}

body {
  width: 99%;
  height: 99%;
  margin: 0;
  display:contents;
}

header {
  height: 20%;
  background: green;
  width: 100%;
}

main {
  width: 100%;
  height: 89%;
  background: rgb(255, 255, 255);
  overflow-y: scroll;
}

footer {
  border: 0ch;
  position: fixed;
  left: 0;
  bottom: 0;
  width: 100%;
  text-align: center;
  background: rgb(153, 153, 153);

}

/*
footer{
  margin: auto;
  width: 97%;
  position: absolute;
  bottom: 8px;
  left: 16px;
}
*/
form{
  /*width: 300px;*/
  /*margin: 20% 0% 0% 5%;*/
  text-align: center;
  margin: auto;
}

input{
  display: block;
  margin: 10px auto;
  width: 250px;
  height: 30px;
}

table{
  table-layout: auto;
  width: 75%;
  border-collapse: collapse;
  border: 3px solid;
  margin:auto;
  
}

thead th:nth-child(1) {
    width: 5%;
  }
  
thead th:nth-child(2) {
    width: 30%;
  }
  
thead th:nth-child(3) {
    width: 15%;
  }
  
thead th:nth-child(4) {
    width: 15%;
  }
  
th,
td {
    padding: 20px;
  }