Here the CodePen: http://codepen.io/BamiGorengo/pen/vXEmXX
I got the content area and the sidebar area. i tryed to do my best, to make it totaly responsive, but the div with the class "chat" dont geht the correct height on some resolutions...
html {
box-sizing: border-box; }
*, *::after, *::before {
box-sizing: inherit; }
html {
height: 100%; }
html body {
height: 100%;
background-color: #fff;
margin: 0;
font-family: "Ubuntu", sans-serif; }
header {
height: 80px;
padding: 1em;
display: -webkit-box;
display: -moz-box;
display: box;
display: -webkit-flex;
display: -moz-flex;
display: -ms-flexbox;
display: flex;
background-color: #404040;
box-shadow: 0px 0px 3px 1px rgba(0, 0, 0, 0.48); }
html body .live-chat {
height: calc(100% - 80px);
display: -webkit-box;
display: -moz-box;
display: box;
display: -webkit-flex;
display: -moz-flex;
display: -ms-flexbox;
display: flex; }
html body .live-chat .main {
width: 100%;
display: -webkit-box;
display: -moz-box;
display: box;
display: -webkit-flex;
display: -moz-flex;
display: -ms-flexbox;
display: flex;
-webkit-box-orient: vertical;
-moz-box-orient: vertical;
box-orient: vertical;
-webkit-box-direction: normal;
-moz-box-direction: normal;
box-direction: normal;
-webkit-flex-direction: column;
-moz-flex-direction: column;
flex-direction: column;
-ms-flex-direction: column; }
@media screen and (min-width: 768px) {
html body .live-chat .main {
width: 72%; } }
html body .live-chat .main .live-video {
background-position: 50%;
background-color: #0c0c0c; }
@media screen and (min-width: 992px) {
html body .live-chat .main .live-video {
padding: 0 80px; } }
@media screen and (min-width: 1200px) {
html body .live-chat .main .live-video {
padding: 0 120px; } }
@media screen and (min-width: 1500px) {
html body .live-chat .main .live-video {
padding: 0 240px; } }
html body .live-chat .main .live-video img,
html body .live-chat .main .live-video video {
width: 100%;
display: block; }
html body .live-chat .main .chat {
display: -webkit-box;
display: -moz-box;
display: box;
display: -webkit-flex;
display: -moz-flex;
display: -ms-flexbox;
display: flex;
-webkit-box-orient: vertical;
-moz-box-orient: vertical;
box-orient: vertical;
-webkit-box-direction: normal;
-moz-box-direction: normal;
box-direction: normal;
-webkit-flex-direction: column;
-moz-flex-direction: column;
flex-direction: column;
-ms-flex-direction: column;
-webkit-flex-grow: 1;
-moz-flex-grow: 1;
flex-grow: 1;
-ms-flex-positive: 1; }
html body .live-chat .main .chat ul {
min-height: 140px;
margin: 0;
padding: 20px;
-webkit-flex-grow: 1;
-moz-flex-grow: 1;
flex-grow: 1;
-ms-flex-positive: 1;
overflow-x: hidden;
overflow-y: auto;
background-color: #404040; }
html body .live-chat .main .chat ul li {
list-style: none; }
html body .live-chat .main .chat ul li .msg {
color: #fff; }
html body .live-chat .main .chat ul li.me .name {
color: #4183D7; }
html body .live-chat .main .chat ul li.other .name {
color: #F62459; }
html body .live-chat .main .chat .chat-input input {
width: 100%;
padding: 8px; }
html body .live-chat .sidebar {
width: 320px;
min-width: 320px;
height: calc(100% - 80px);
padding: 10px;
top: 80px;
right: -320px;
position: fixed;
background-color: #242424; }
@media screen and (min-width: 768px) {
html body .live-chat .sidebar {
width: 28%;
height: 100%;
position: inherit; } }
@media screen and (min-width: 1200px) {
html body .live-chat .sidebar {
padding: 20px; } }
html body .live-chat .sidebar.open {
right: 0; }
html body .live-chat .sidebar .widget {
margin-bottom: 10px;
padding: 10px;
color: #fff;
background-color: #0c0c0c;
border-top-left-radius: 4px;
border-top-right-radius: 4px;
border-bottom-left-radius: 4px;
border-bottom-right-radius: 4px; }
html body .live-chat .sidebar .widget:last-child {
margin-bottom: 0; }
@media screen and (min-width: 1200px) {
html body .live-chat .sidebar .widget {
margin-bottom: 20px;
padding: 20px; } }
html body .live-chat .sidebar .widget h1 {
margin: 0; }
html body .live-chat .sidebar .widget .additional-info {
padding-top: 10px;
font-size: 14px; }
html body .live-chat .sidebar .widget .user-images {
padding: 10px 0;
max-width: 1200px;
margin-left: auto;
margin-right: auto; }
html body .live-chat .sidebar .widget .user-images::after {
clear: both;
content: "";
display: block; }
html body .live-chat .sidebar .widget .user-images > div {
float: left;
display: block;
margin-right: 2.35765%;
width: 31.76157%; }
html body .live-chat .sidebar .widget .user-images > div:last-child {
margin-right: 0; }
html body .live-chat .sidebar .widget .user-images > div img {
width: 100%;
display: block; }
html body .live-chat .sidebar .widget a {
padding: 6px 10px;
color: #fff;
text-align: center;
text-decoration: none;
display: block;
background-color: #F62459;
border: 1px solid #fa7c9b;
border-top-left-radius: 4px;
border-top-right-radius: 4px;
border-bottom-left-radius: 4px;
border-bottom-right-radius: 4px; }
html body .live-chat .sidebar .widget a:hover {
background-color: #f10a44;
border: 1px solid #fb92ac; }<html>
<head>
<title>Fun Chat</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
</head>
<body>
<header>
Logo
</header>
<div class="live-chat">
<section class="main">
<div class="live-video">
<img src="https://upload.wikimedia.org/wikipedia/commons/c/c4/PM5544_with_non-PAL_signals.png">
</div>
<div class="chat">
<ul>
<li class="me"><span class="name">John</span> <span class="msg">Hallo?</span></li>
<li class="other"><span class="name">John</span> <span class="msg">Hallo!</span></li>
</ul>
<div class="chat-input">
<input>
</div>
</div>
</section>
<aside class="sidebar">
<section class="widget user-info">
asd
</section>
<section class="widget">
asd
</section>
<section class="widget">
asd
</section>
</aside>
</div>
</body>
</html>