body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f8f9fa;
}
        
header {
    text-align: center;
    padding: 20px 0;
}

header img {
    width: 100px;
}

h1 {
    font-size: 50px;
    margin-bottom: 25;
    text-align: center;
}

h2 {
    font-size: 30px;
    margin-bottom: 15px;
    text-align: center;
}

table {
    width: 100%;
    margin-bottom: 20px;
    border-collapse: collapse;
}

table, th, td {
    border: 1px solid #dee2e6;
}

th, td {
    padding: 12px;
    text-align: left;
}

th {
    background-color: #343a40;
    color: #fff;
}

tbody tr:nth-child(odd) {
    background-color: #f8f9fa;
}

tbody tr:nth-child(even) {
    background-color: #e9ecef;
}

button {
    background-color: #007bff;
    border: none;
    color: white;
    padding: 10px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border-radius: 4px;
}

button:hover {
    background-color: #0056b3;
}

select {
    width: 100%;
    padding: 10px;
    border: 1px solid #ced4da;
    border-radius: 4px;
    box-sizing: border-box;
}

#preloader {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 9999;
    overflow: hidden;
    background: #fff;
}

#preloader:before {
    content: "";
    position: fixed;
    top: calc(50% - 30px);
    left: calc(50% - 30px);
    border: 6px solid #f2f2f2;
    border-top: 6px solid #56829e;
    border-radius: 50%;
    width: 60px;
    height: 60px;
    -webkit-animation: animate-preloader 1s linear infinite;
    animation: animate-preloader 1s linear infinite;
}

@-webkit-keyframes animate-preloader {
    0% {
        -webkit-transform: rotate(0deg);
        transform: rotate(0deg);
    }
    100% {
        -webkit-transform: rotate(360deg);
        transform: rotate(360deg);
    }
}

@keyframes animate-preloader {
    0% {
        -webkit-transform: rotate(0deg);
        transform: rotate(0deg);
    }
    100% {
        -webkit-transform: rotate(360deg);
        transform: rotate(360deg);
    }
}