* {
}

html {
	background-color: black;	
	zoom: 75%;
}


code {
  display: block;
  white-space: pre-wrap;
  max-width: 70%;
  margin: auto;
  font-size: 0.6cm;
  border: 3px dashed black;
  padding: 7px;
  border-radius: 25px;
  background: url(https://astro.uni-frankfurt.de/wp-content/uploads/2014/01/White-Paper-Texture-Background-520x390.jpg);
  background-size: cover;
}

.links_list  {
    text-align: center;
    font-size: 1cm;
}

.main_text {
    border: 5px solid grey;
    background-color: white;
    width: 40cm;
    margin: auto;
    padding-bottom: 5cm;
    border-radius: 25px;
}

body {
    margin: auto;
    padding: 10px;
    margin-top: 1cm;
}

h1,h2,h3,h4,h5 {
    text-align: center;
    font-family: 'Times New Roman', serif;
    padding-bottom: 0px;
    margin-bottom: 0px;
}

h4 {
    font-size: 0.9cm;
    margin-bottom: 0.1cm;
}

h3 {
    font-size: 1.0cm;
    margin-bottom: 0.3cm;
}

h2 {
    font-size: 1cm;
    text-decoration: underline;
    margin-bottom: 0.5cm;
}

h1 {
    font-size: 1.5cm;
}

hr {
    margin-bottom: 0.8cm;
}

p {
    font-size: 0.8cm;
    width: 95%;
    margin: auto;
    text-indent: 50px;
}

ol {
  display: block;
  max-width: 70%;
  margin: auto;
  font-size: 0.6cm;
  border: 3px dashed black;
  border-radius: 25px;
  background: url(https://astro.uni-frankfurt.de/wp-content/uploads/2014/01/White-Paper-Texture-Background-520x390.jpg);
  background-size: cover;
  padding-bottom: 2px;
  padding-top: 2px;
  counter-reset: item;
}
li {
    padding-top: 2px;
    padding-bottom: 2px;
    counter-increment: item;
}
ol ol {
  border: none;
}
ol ol > li {
    display: block;
}

ol ol > li:before {
    content: counters(item, ".") ". ";
    margin-left: -100px;
}

img {
    display: block;
    margin-left: auto;
    margin-right: auto;
    max-width: 50%; 
}

video {
    margin: auto;
    display: block;
    max-width: 70%;
    margin-bottom: 10px;
}

iframe {
    margin: auto;
    display: block;
    max-width: 70%;
    margin-bottom: 10px;
    margin-top: 10px;
    width: 50%;
    height: 40%;
}
u {
  border-bottom:2px dotted red;
}

div.top_bar {
  position: fixed;
  bottom: 30px;
  width: 200px;
  border: 5px solid grey;
  background: white;
  border-radius: 25px;
  text-align: center;
  font-size: 0.9cm;
}

div.top_bar:hover {
  background: pink;
}

a.main_page {
    color:#0090FF;
}
a.main_page:hover{ 
    color:pink; 
}
.parent {
  position: relative;
  top: 0;
  left: 0;
}
.image1 {
  position: relative;
  top: 0;
  left: 0;
  border: 1px red solid;
}
.image2 {
  position: absolute;
  top: 30px;
  left: 30px;
  border: 1px green solid;
}

table {
    border-collapse: collapse;
    margin: 25px 0;
    font-size: 0.8cm;
    font-family: sans-serif;
    min-width: 400px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.15);
    background: url(https://astro.uni-frankfurt.de/wp-content/uploads/2014/01/White-Paper-Texture-Background-520x390.jpg);
    border-radius: 10px;
	text-align: center;
}

thead tr {
    background-color: #009879;
    color: #ffffff;
    text-align: left;
}

th {
    padding: 12px 15px;
}
td {
    padding: 12px 15px;
    border: 3px solid black;
}

tbody tr {
    border: 3px solid black;
}