body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    font-family: "Verdana";
    font-size: 13px;
    text-align: center;
    background-color: #f5f5f5;
    background:url("./back.jpg");
    background-size: cover;
    background-repeat: no-repeat;
    background-position: top center;
    overflow-x: hidden;
}
a { text-decoration: none; color: #000; }
input:invalid { border: 1px dashed red; }
table { width: 100%; table-layout: fixed; text-align: left; }
button { background: #e5e5e5; color: #000; border: #000 0.5px solid; }
button:hover { opacity: 0.8; }
button[disabled] { background: #c4c4c4; color:#767676; border: #707070 1px solid; cursor: default; pointer-events: none; text-decoration: none;}
.disabled { color:#d1d1d1; cursor: default; pointer-events: none; text-decoration: none; }
.right_bound { text-align: right;}
.center_bound { text-align:center;}
.left_bound { text-align: left;}
.filler {height: 10px; }