body {
  background-image: url('https://i.imgur.com/gb5mD0u.png');
  background-repeat: no-repeat;
  background-attachment: fixed;
  background-size: 100% 100%;
  font-family: Arial;
}

.post {
  background-color: white;
  margin-left: 10%;
  margin-right: 10%;
  padding: 20px;
  border-radius: 15px;
  margin-bottom: 20px;
}

h1 {
  font-weight: bold;
  font-size: 24px;
  margin: auto;
}

hr {
  border-color: black;
}

img {border: 3px solid black;margin: 10px;}
  th { background-color:lightgray}
  table {border:3px solid black}
  td {border: 2px solid lightgray;background-color:white;}
  .bold { font-weight: bold; }
  .red { color: #FF0000; }
  .blue { color: #0000FF; }
  
@media screen and (max-width: 900px) {
.post {
  margin: 0;
}
  
}