File: _style.css

body{
font: 12px/1.42 BlinkMacSystemFont, "Segoe UI", 
Roboto, Helvetica, Arial, sans-serif; 
background-color:#def; color: #333;
border:0; margin:0em 4px 0; padding:0 0 .2em; 
}
h1,h2,h3,h4,h5,h6{
font-weight:400;
font-family: /*-apple-system,*/ BlinkMacSystemFont,
"Segoe UI",Roboto,Oxygen,Ubuntu,Cantarell,"Fira Sans","Droid Sans",
Inconsolata,"Helvetica Neue",Arial,sans-serif;
color:#345;
} 
dt {margin-top: 1em;}
table tr th,
table tr td {padding:0em 0.42em; text-align: left;}
table tr td {border:solid 0px #ccc;}
table tr th {background-color: #ddd;}
 
label {display:inline-block; width:6em; color:#777;}
.btn  {display:inline-block; border:outset 1px;
       padding:0.12em 0.21em; margin:0.42em;}
.btn:hover {background-color: snow; color:#00f;}

.bdr {border:solid 1px #999;}
.bd1 {border:solid 1px #ddf;}
.bga {background-color: aqua;} .bgl {background-color: #cfc;} 
.bge {background-color: #eee;} 
.bgs {background-color: snow;}
.dib {display:inline-block;}
.fge {color:#ddf;} .fgg {color:#0d0;} .fgb {color:#00d;}
.fll {float:left;} .flr {float:right;}
.fss {font-size: small;} .fsl {font-size: large;} .fsn {font-size:88%;}
.fwb {font-weight: 700;}
.hhh {display:none; line-height:0;}
.mga {margin:0 auto;} .mg1 {margin: 1em auto;} .mg2 {margin: 1em auto 0;}
.ok  {color: lime;}
.ooo {padding:0; margin:0;} 
.POF {position:fixed; left:0; bottom:0;}
.p42 {padding:0.42em;}
.red {color:#f00;}
.tac {text-align:center;} .tal {text-align: left;}
.tdn {text-decoration: none;}
.warn{color:red;} .info {color:#080;}
.w06 {width: 4em;}
.w12 {width:12em;}
.w88 {width:88%; max-width:888px;} .w99 {width:100%;}
.z-2 {z-index:2;}    

.flex-container {
  display: flex;
  justify-content: center;
  /*
  background-color: DodgerBlue;
  space-between: 42px;
  */
}
.flex-container > input  {
  margin: 1em 1em;
  text-align: center;
}