/* An external CSS file with at least 20 CSS properties. Must use at least a Flexbox */
/*  color combinations
    color: #FF5733;
    color: #33C1FF;
    color: #33FF57;
    color: #FF33A8; */
*{
  font-family: "WDXL Lubrifont TC", sans-serif;
  font-weight: 400;
  font-style: normal;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
}
body{
    background-color: #f0f0f0;
    margin: 0;
    padding: 0;
}
#main_body{
    background: linear-gradient(
          rgba(0, 0, 0, 0.5), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/cnn.jpeg');
    background-size: cover;
    background-repeat: no-repeat;
    color: white;
}
#db_body{
    background: linear-gradient(
          rgba(0, 0, 0, 0.7), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/db.jpg');
    background-size: cover;
    background-repeat: no-repeat;
    color: white;
}
#hci_body{
    background: linear-gradient(
          rgba(0, 0, 0, 0.7), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/hci.png');
    background-size: cover;
    background-repeat: no-repeat;
    color: white;
}
#emb_body{
    background: linear-gradient(
          rgba(0, 0, 0, 0.7), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/emb.jpeg');
    background-size: cover;
    background-repeat: no-repeat;
    color: white;
}
h1{
    font-size: 2.5em;
    text-align: center;
    
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 2px;
}
#t0{
    color: #4A90E2;
}
#t1{
    color: #33C1FF;
}
#t2{
    color: #FF5733;
}
#t3{
    color: #33FF57;
}
nav{
    background-color: #f8f8f8;
    padding: 10px 0;
}
ul{
    list-style: none;
    display: flex;
    justify-content: center;
    margin: 0;
    padding: 0;
    
}
ul li{
    margin: 0 auto;
}
ul li a{
    margin: 0 auto;
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}
ul li a:hover{
    color: #4A90E2;
}
.continer{
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #ffffff;
    border-radius: 8px;
    margin-bottom: 20px;
    line-height: 1.6;
    color: #555;
    font-size: 1.1em;
    border: 1px solid #e0e0e0;
    color: white;
    background-size: cover;
    background-repeat: no-repeat;
}
#a1{
    background-color: #E8F0FE;
    background: linear-gradient(
          rgba(0, 0, 0, 0.7), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/db.jpg');
}
#a1 button{
    background-color: #E8F0FE;
    color: #000;
}
#a2{
    background-color: #FDEFE8;
    background: linear-gradient(
          rgba(0, 0, 0, 0.7), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/hci.png');
}
#a2 button{
    background-color: #FDEFE8;
    color: #000;
}
#a3{
    background-color: #E8FDF5;
    background: linear-gradient(
          rgba(0, 0, 0, 0.7), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/emb.jpeg');
}
#a3 button{
    background-color: #E8FDF5;
    color: #000;
}
#a4{
    background-color: #F3E8FD;
    background: linear-gradient(
          rgba(0, 0, 0, 0.5), 
          rgba(0, 0, 0, 0.7)
        ),url('./assets/img/cnn.jpeg');
}
#a4 button{
    background-color: #F3E8FD;
    color: #000;
}
.btn{
    border: none;
    padding: 10px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border-radius: 5px;
    transition: background-color 0.3s, transform 0.2s;
}
.btn:hover{
    background-color: #357ABD;
    transform: scale(1.05);
}