body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
body{
  color:white !important;/*override ALL defaults*/
  background-color:teal !important;
}
a {/*MUST or else <a> default color will be blue*/
  color: inherit;
}
body.dark-mode {
  color:darkgoldenrod !important;
  background-color: white !important;
}
body.dark-mode a {/*MUST*/
  color: inherit;
}
/* ***************************** */
header {
  position: fixed;
  width: 100%;
  top: 0;
  align-items: center;
  display: flex;
  justify-content: space-between;
}
.mainNav {
  display: flex;
  gap: 30px;
  align-items: center;
}
#slogan {
  font-size: 35px;
  font-weight:900;
  text-shadow: 15px 15px 5px rgba(0, 0, 0, 0.9);
}
header a {
  font-weight: 900;
  text-shadow: 15px 15px 5px rgba(0, 0, 0, 0.9);
}
/* ***************************** */
main {
  display: flex;
  flex: 1;
  overflow-x: hidden;
  background-size: auto;
}
.sideNav {
  margin-top: 65px;
  width: 20%;
  z-index: 1;
}
#ol {
  list-style-type: decimal;
  padding-left: 35px;
  margin: 0;
}
li a {
  padding: 5px;
  z-index: 1;
  display: block;
}
a:hover {
  scale: 1.1;
}
/* ***************************** */
#mainSection {
  left: 20%;
  width: 100%;
  top: 90px;
  bottom: 10px;
  overflow-y: auto;/*vertical Scrollable*/
}
#pic {
  width: 100%;
}
/* ***************************** */
.iframe-container {
  display: none;
  left: 15%;
  width: 85%;
  position: fixed;
  top: 65px;
  overflow-y: auto;
}
.preview-container {
  display: block;
  width: 100%;
}
iframe {
  width: calc(100% - 20px);
  height: 100vh;
}
.sideNav ol li a:hover+.iframe-container,
.iframe-container:hover {
  display: block;
}
/* ***************************** */
footer {
  display: flex;
  position: fixed;
  bottom: 0;
  width: 100%;
  justify-content:space-evenly;
  font-weight: 900;
  text-shadow: 15px 15px 5px rgba(0, 0, 0, 0.9);
}
footer a:hover {
  scale: 1.1;
};