body {
  font-family: 'Arial Narrow', sans-serif;
}

html {
  background: url(green.jpeg) no-repeat center center fixed;
  background-size: cover;
}

p {
  font-size: 20px;
}
.header {
  height: 200px;
  width: 100%;
  background-color: darkgreen;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
}

.spacer {
  height: 80px;
  width: 100%;
  background-color: dimgrey;
}

.intro {
  background-color: lightgray;
  width: 90%;
  margin: auto;
  padding: 20px;
  border-radius: 10px;
}

.image-box {
  width: 90%;
  height: 400px;
  background-image: url(checking.png);
  background-size: cover;
  background-position: center;
  margin: 20px auto;
  border-radius: 10px;
}

.tab-container {
  width: 95%;
  margin: auto;
  background-color: darkgrey;
  padding: 20px;
  border-radius: 10px;
}

.tab-container button {
  font-size: 20px;
  margin: 5px;
  padding: 10px 20px;
  cursor: pointer;
}

.button-container {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
}

.square-button {
  width: 150px;
  height: 150px;
  font-size: 20px;
  background-color: #138808;
  color: #D0F0C0;
  border: 2px solid #004526;
  border-radius: 5px;
  cursor: pointer;
}

.s {
  font-size: 35pt;
  text-align: center;
}

@media(max-width: 900px) 
{
    .square-button {
    width: 120px;
    height: 120px;
    font-size: 16px;
  }

  .p {
    font-size: 28pt;
  }
 .intro, .image-box, .tab-container 
    {
    width: 95%;
  }
}