* {
  box-sizing: border-box;
}

/* ----------------------------------------------------------
  Header style
------------------------------------------------------------*/
header {
  border: 1px solid white;
  background-image: url("../img/header-bg.jpg");
  height: 80px; 
  position: sticky;
  top: 0px;
}
header > h1 {
  color: white;
  text-align: center;
}

/* ----------------------------------------------------------
  Footer style
------------------------------------------------------------*/
footer {
  border: 1px solid white;
  color: white;
  background: rgb(23, 39, 39);
  text-align: center;
}

/* ----------------------------------------------------------
  Menu style
------------------------------------------------------------*/
#top-menu {
  /* border: 1px solid black; */
  position: sticky;
  /* top: 0px; */
  top: 80px;
  background-color: white;
}
#top-menu ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  /*border: 1px solid #e7e7e7;*/
  /* background-color: ivory; */
}
#top-menu li {
  float: left;
}
#top-menu li a {
  display: block;
  color:darkslategray;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  background-color: white;
}
#top-menu li a:hover:not(.active) {
  background-color:rgb(168, 190, 212);
}
#top-menu li a.active {
  color: white;
  background-color: darkslategray;
}

/* ----------------------------------------------------------
  Left side column style
------------------------------------------------------------*/
#left-column {
  border: 1px solid white;
  background:white;
  margin-right: 10px;
}
#left-column img {
  width: 150px;
  padding-top: 10px;
}

/* ----------------------------------------------------------
  ...
------------------------------------------------------------*/

main {
  border: 1px solid white;
}
.mid-section {
  border: 1px solid white;
  display: flex;
}
.center-section {
  border: 1px solid white;
}


article {
  border: 1px solid white;
  background: white;
  margin-left: 14px;
}

a.anchor {
  display: block;
  position: relative;
  /* top: -40px; */
  top: -120px;
  visibility: hidden;
}