.navbar {
    margin-bottom: 50px;
    border-radius: 0;
}
.jumbotron {
    margin-bottom: 0;
    background-image: url("../Images/library.jpg");
    background-size: cover;
    background-attachment: fixed;
}
.quantity,.quantity1,.quantity2,.quantity3,.quantity4,.quantity5,.quantity6,.quantity7,.quantity8,.quantity9{
  width: 50px;
}
.jumbotron h1{
  text-transform: uppercase;
  font-family: monospace;
  font-size: 75px;
  color: rgb(10, 34, 245);
  font-weight: 800;
}
.btn{
  font-family: monospace;
  font-size: 18px;
  font-weight: 600;
  text-align: center;
}
.dropdown-menu a{
  color: black;
  text-decoration: none;
  font-family: monospace;
  font-weight: 500;
  font-size: 16px;
}
.dropdown-menu a:hover{
  background-color: rgb(27, 15, 139);
  color: white;
  padding: 5px;
  border-radius: 10px;
}
#categories{
  position: relative;
}
#myBtn {
  display: none;
  position: fixed;
  bottom: 20px;
  right: 10px;
  z-index: 99;
  font-size: 18px;
  border: none;
  outline: none;
  background-color: rgb(8, 24, 168);
  color: white;
  cursor: pointer;
  padding: 10px;
  border-radius: 4px;
}
#myBtn:hover {
  background-color: #555;
}
#back{
  background-image: url("../Images/libu.jpg");
  width: 100%;
  height: 650px;
  background-repeat: no-repeat;
  background-size: cover;
  text-align: center;
  font-size: 20px;
  color: white;
}
#blue{
  margin-left: 20%;
  padding: 20px;
  background-color: black;
  opacity: 0.7;
  width: 700px;
  height: 650px;
  font-family: monospace;
}
footer {
    background-color: #f2f2f2;
    padding: 25px;
}
#contacts{
  height: 700px;
  background-image: url("../Images/contact.jpg");
  background-size: cover;
  display:inline-block;
  text-align: center;
  color: white;
  width: 100%;
}
#contacts h1{
  font-weight: 600;
  color: white;
}
form{
  height:400px;
}
input[type=text], textarea {
  width: 50%;
  color: white;
  font-size: 18px;
  padding: 20px;
  border: 1px solid #ccc;
  border-radius: 4px;
  box-sizing: border-box;
  margin-top: 6px;
  margin-bottom: 16px;
  resize: vertical;
}

input[type=submit] {
  background-color: rgb(71, 3, 134);
  color: black;
  padding: 12px 20px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}
#mebtn{
  background-color: white;
  padding: 10px;
  border:none;
  color: black;
  border-radius: 10px;
}
#mebtn:hover {
  background-color: #45a049;
}