.table {
   display: table;
}
.table-row {
   display: table-row;
}
.table-cell {
   display: table-cell;
}

html { 
  box-sizing: border-box; 
  background: #d5d5d5;	
} 

*, ::before, ::after { 
  box-sizing: inherit; 
}

body {
	max-width: 100em;
	margin:0 auto;
	padding: 0;
	background: #fff;	
	color: #333; 
	font: normal 1em Arial, sans-serif;  /* Mindestschriftgröße wird dem Browser, bzw. dem Nutzer überlassen! */
                    
}
<style type="text/css">
	.auto-style1 {
		font-size: large;
	}
	.auto-style2 {
		font-size: medium;
	}
	.auto-style3 {
		border-bottom-style: solid;
		border-bottom-width: 1px;
	}
	.auto-style4 {
		border-top-style: solid;
		border-top-width: 5px;
	}
	
ul,li {
  margin: 0px 2px;
}

#wrapper {
  background-color: #FFFFFF;
  margin: 0 auto;
}
/* oben*/
div#top {
  margin: 0 auto;
  padding: 0;
  background-color: #116A26;
  color: #000000;
}

.toptext {
	margin: 0 auto;
	padding: 5px 0px 0px 10px;
	font-size: 1.2em;
	font-family: "arial",georgia,calibri,serif;
	font-weight: bold;
	background-color: #116A26;
	color: #FFFFFF;
	text-shadow: 1px 1px 2px #3F3F3F;
}

header {
  margin: 0 auto;
  padding: 0;
  background-color: #d5d5d5;
}

div#headerleft {
	margin: 0;
	padding-left: 5%;
	text-align: left;
	background:url(images/gradient.jpg) repeat-x;
	color: #FFFFFF;
	float: left;
	width: 100%;
	height: 130%
}

/*div#headerright {
  padding-right: 5%;
  background-color: #d5d5d5;
  color: #FFFFFF;
  float: right;
  text-align: right;
  width: 44%;
}*/

.headertextbig {
  font-size: 1.5em;
  font-family: "arial",georgia,calibri,serif;
  letter-spacing: 2px;
  padding-top: 70px;
  text-shadow: 1px 1px 2px #303030;
}

.headertextsmall {
  font-size: 1em;
  font-family: "arial",georgia,calibri,serif;
  letter-spacing: 2px;
  padding-top: 5px;
  text-shadow: 1px 1px 2px #303030;
}

#subtitle {
  font-size: 1em;
  padding: 5px;
  line-height: 20px;
  margin-bottom: 12px;
  border-bottom: 1px solid #999999;
}

/* Hauptteil*/
main {
  background-color: #FFFFFF;
 /* background:url(images/gradient.jpg) repeat-x;*/
  padding: 0;
  margin: 0 auto;
  display: block;  /*wegen Fehldarstellung IE*/
}

#main-inner {
  margin: 0 auto;
  padding: 1% 5%;
}
/* Navigation links*/
aside {
  font-size: 1em;
  width: 22%;
  float: left;
  padding: 2px;
}

aside h2 {
  color: #ffffff;
  background-color: #116A26;
  font-size: 1.2em;
  font-weight: bold;
  margin: 10px 0px;
  padding: 5px;
  font-family: "arial",calibri,georgia,serif;
  letter-spacing: 1px;
  line-height: 20px;
}
nav {
  list-style-type:none;
  padding: 0px;
  margin: 0px;
  text-align: left;
  background-color: transparent;
}

nav ul {
  list-style-type:none;
  padding: 0;
  margin: 0;
}

nav li {
  list-style: none;
  margin: 0;
  padding: 0;
}

nav ul a:link,
nav ul a:visited,
nav ul a:active {
  color: #333333;
  background-color: transparent;
  padding: 3px;
  margin: 0;
  text-decoration: none;
  font-size: 1em;
  font-family: "arial",calibri,georgia,serif;
  display: block;
  font-weight: normal;
  line-height: 1.6em;
  border-bottom: 1px solid #999999;
  
}

nav ul a:hover,
nav ul a:focus {
  font-weight: bold;
  text-decoration: none;
  font-family: "arial",calibri,georgia,serif;
  color: #000000;
  font-weight: normal;
  background-color: #ECECEC;
}

nav .submenu {
	visibility: hidden;
	height: 0;
	z-index: 1000;
}

nav .submenu li {
	display: block;
	/* width: 15em; */
}
/**     Show the submenu on hover, focus     **/
nav .submenu li {
	text-indent: 50px;
	/* width: 15em; */
}

nav li:hover .submenu,
nav li:active .submenu,
nav li:focus .submenu {
	visibility: visible;
	height: auto;
}

nav li:focus-within .submenu {
	visibility: visible;
	height: auto;
}
/* Inhalt*/
article {
  margin-left: 27%;
  padding: 10px 0;
  font-size: 1em;
  font-weight: normal;
  text-align: left;
  line-height: 1.5em;
}
article h1 {
  font-size: 1.5em;
  margin: 0;
  color: #000000;
  font-family: "arial",georgia,calibri,serif;
  letter-spacing: 1px;

}
article h2 {
  color: #808080;
  background-color: inherit;
  font-family: "arial",georgia,calibri,serif;
  font-size: 1.4em;
  text-align: left;
  margin: 3px;
  padding: 2px;
  text-shadow: 1px 1px 2px #7F7F7F;
}
article h3 {
  color: #116A26;
  background-color: inherit;
  font-family: "arial",georgia,calibri,serif;
  font-size: 1.2em;
  font-style: italic;
  padding-left: 5px;
  font-weight: normal;
  text-shadow: 1px 1px 2px #3F3F3F;
}
article h4 {
  color: #116A26;
  font-size: 1em;
  font-weight: bold;
  margin: 0px;
  padding: 2px;
  font-family: "arial",georgia,calibri,serif;
  letter-spacing: 1px;
  text-shadow: 1px 1px 2px #3F3F3F;
  text-align: center;
}
article h5 {
  color: #333333;
  background-color: inherit;
  font-family: "arial",georgia,calibri,serif;
  font-size: 1em;
  font-weight: bold;
  margin: 2px;
  letter-spacing: 2pt;
  padding: 0;
  text-shadow: 1px 1px 2px #3F3F3F;
}
article p {
  margin: 8px 2px;
}
 /*unten*/

footer {
  margin: 0 auto;
  padding: 0;
  text-align: center;
  color: #000000;
  background-color: #A4A4A4;
}

.fussinhalt  {
  margin: 0 auto;
  font-size: 16pt;
  font-family: "arial",calibri,georgia,serif;
  font-weight: bold;
  letter-spacing: 1px;
  background-color: transparent;
  color: #000000;
}

div#footerinnerbox1  {
  width: 15%;
  margin: 1% 1% 1% 30%;
  font-family: "arial",georgia,calibri,serif;
  font-weight: bold;
  letter-spacing: 1px;
  float:left;
  background-color: transparent;
  text-align: left;
}

div#footerinnerbox1 h2 {
  margin: 0;
  padding: 0;
  font-size: 1.2rem;
  font-variant:small-caps;
  color: #000000;
  background-color: transparent;
  text-align: left;
  border-bottom: 0px solid #FFFFFF;
  line-height: 1.2em;
  text-shadow: 1px;
}

div#footerinnerbox2  {
  margin: 1% 1% 1% 10%;
  padding: 0;
  width: 25%;
  font-family: "arial",calibri,georgia,serif;
  font-weight: bold;
  float:left;
  text-align: left;
  font-size: 0.875rem;
  font-weight: normal;
  text-align: justify;
}

div#footerinnerbox2 h2 {
  margin: 0;
  padding: 0;
  font-size: 1.4rem;
  font-variant:small-caps;
  color: #000000;
  background-color: transparent;
  text-align: left;
  border-bottom: 1px solid #000000;
  line-height: 1.4rem;
  text-shadow: 1px 1px 2px #303030;
}

.footermenue {
  list-style-type:none;
  padding: 5px 0px 0px 0px;
  margin: 0;
  text-align: left;
  background-color: transparent;
  color: #000000;
}

.footermenue li a, .footermenue li a:active, .footermenue li a:visited, .footermenue a {
  color: #000000;
  background-color: transparent;
  padding: 1px;
  margin: 0;
  text-decoration: none;
  font-size: 0.875rem;
  font-family: "arial",georgia,calibri,serif;
  display: block;
  font-weight: normal;
}

.footermenue li a:hover {
  font-weight: bold;
  text-decoration: none;
  font-family: "arial",georgia,calibri,serif;
  color: #000000
  background-color: transparent;
}

.footerlink {
  text-align: center;
  font-size: 0.5rem;
  color: #000000;
  background-color: #A4A4A4;
}

/* allgemeine Angaben*/

a:link, a:visited, a:active {
	color: #000000;
	background-color: transparent;
	text-decoration: none;
	font-weight: bold;
	padding: 0;
	margin: 0;
}
a:hover {
  color: #000000;
  background-color: transparent;
  text-decoration: underline;
}

.clear {
 clear: both;
 margin: 0;
 padding: 0;
 line-height: 1px;
}

img {
  border: 0;
  max-width: 100%;
  height: auto;
  display: block;
}

/******************Besonderheiten für Bildschirmgroesse max. 768px**********************/

@media (max-width: 768px) {

header {
  font-size: 0.7em;
}

.headertext {
  padding: 2px;
  letter-spacing: 1px;
  margin: 3px;
  line-height: 1em;
  text-align: center;
  float: none;
}

.headertextbig {
  font-size: 14pt;
  padding-top: 30px;
}

#topnavi {
  float: none;
  text-align: center;
  margin-top: 2px;
  padding-top: 0;
}

aside {
  float: none;
  width: 80%;
}

article {
 margin: 0;
 width: 80%;
}

div#footerinnerbox1 {
  letter-spacing: 1px;
  margin: 0 auto;
  float: none;
  width: 90%;
}

div#footerinnerbox2 {
  letter-spacing: 1px;
  margin: 0 auto;
  float: none;
  width: 90%
}

}

/*****************Besonderheiten für Bildschirmgroesse max. 640px***********************/

@media (max-width: 640px) {

h1,h2,h3,h4,h5 {
  font-size: 1em;
}

div#headerright {
  float: none;
  width: 95%;
}

}

/*****************Besonderheiten für Bildschirmgroesse max. 480px***********************/

@media (max-width: 480px) {

.headertext {
  padding: 1px;
  letter-spacing: 1px;
  margin: 1px;
}

article {
  padding: 2px;
  margin: 0 auto;
  font-size: 1em;
  line-height: 1.338em;
}

.headertextbig {
  font-size: 10pt;
  padding-top: 10px;
}

.fussinhalt h4 {
 padding: 2px;
 font-size: 0.750em;
}

}