body {
  margin: 0;
  font-family: Arial;
}

/**************/
/*top menu*/
/**************/

#menu-container {
  display: flex;
  justify-content:center;
  width:100%;
  background-color:black;"
}

.topnav {
  overflow: hidden;
  background-color: #333;
}

.topnav a {
  float: left;
  display: block;
  color: #f2f2f2;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}

.active {
  background-color: #4CAF50;
  color: white;
}

.topnav .icon {
  display: none;
}

.dropdown {
    float: left;
    overflow: hidden;
}

.dropdown .dropbtn {
    font-size: 17px;    
    border: none;
    outline: none;
    color: white;
    padding: 14px 16px;
    background-color: inherit;
    font-family: inherit;
    margin: 0;
}

.dropdown-content {
    display: none;
    position: absolute;
    background-color: #f9f9f9;
    min-width: 160px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 1;
}

.dropdown-content a {
    float: none;
    color: black;
    padding: 12px 16px;
    text-decoration: none;
    display: block;
    text-align: left;
}

.topnav a:hover, .dropdown:hover .dropbtn {
  background-color: #555;
  color: white;
}

.dropdown-content a:hover {
    background-color: #ddd;
    color: black;
}

.dropdown:hover .dropdown-content {
    display: block;
}

@media screen and (max-width: 600px) {
  .topnav a:not(:first-child), .dropdown .dropbtn {
    display: none;
  }
  .topnav a.icon {
    float: right;
    display: block;
  }
}

@media screen and (max-width: 600px) {
  .topnav {width:100%}
  .topnav.responsive {position: relative;}
  .topnav.responsive .icon {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }
  .topnav.responsive .dropdown {float: none;}
  .topnav.responsive .dropdown-content {position: relative;}
  .topnav.responsive .dropdown .dropbtn {
    display: block;
    width: 100%;
    text-align: left;
  }
}

img {
    max-width: 100%;
    height: auto;
}

/**************/
/*page css*/

#page-container {
  display: flex;
  justify-content: center;
  background-color: lightgray;
}

.page {
  padding: 0px 12px;
  width: 100%;
  max-width: 999px;
  background-color: white;
}

a.sitelink {
   color: green;
}
a.sitelink:hover {
   color: blue;
}

.cont {
    height: 360px;
}

.cont-col {
    border: 1px solid #888;
    border-radius: 5px;
    padding: 5px;
    float: left;
    max-width: 320px;
    margin: 0 5px 5px 0;
    height: 100%;
    background-color: lightyellow;
}

.cont-col-art {
    border: 1px solid #888;
    border-radius: 5px 0px 0px 0px;
    padding: 5px;
    float: left;
    max-width: 640px;
    margin: 0 5px 5px 0;
    height: 100%;
    background-color: #white;
    overflow: scroll;
}

@media screen and (max-width: 600px) {
    .cont-col {
        margin: 0 0px 5px 0;
        max-width: 100%;
    }
    .cont-col-art {
        margin: 0 0px 5px 0;
        max-width: 100%;
        height: auto;
        overflow: auto;
        border-radius: 5px;
    }
}