CSS How do I force a container to be displayed underneath a preceding container whose elements float left - css

Question

I want the div which displays "D" to appear beneath that one which displays "A" so that divs with matching background colours appear stacked over one another. However, I am getting this:
Where exactly in my CSS code must I clear my float?
#container {
background-color: #333333;
width: 990px;
}
#left {
background-color: red;
width: 300px;
float: left;
}
#splitter {
background-color: green;
width: 90px;
float: left;
}
#right {
background-color: blue;
width: 200px;
float: left;
}
<div id="container">
<div id="left">A</div>
<div id="splitter">B</div>
<div id="right">C</div>
</div>
<div id="container">
<div id="left">D</div>
<div id="splitter">E</div>
<div id="right">F</div>
</div>

Answer 1

You have to deal with floats and for this you need to understand what floats and BFC are :
a few ways to do this, that you should understand once you been reading a bit about floats, clearing and Block formating context.
(last example in the snippet below, oldish, even avoids the floats but does the layout)
/* DEMO purpose : Show the id or class being used on that container*/
section:before {
content: attr(id)' 'attr(class);
display: table;
background: #177EE5;
padding: 5px;
margin: 5px;
color: #fff;
text-shadow: 0 0 1px black, 0 0 1px black, 0 0 1px black, 0 0 1px black, 0 0 1px black, 0 0 1px black;
letter-spacing: 1px;
font-variant: small-caps;
}
/* your css turned into class to be valid since used for many tags */
.container {
background-color: #333333;
width: 990px;
}
.left {
background-color: red;
width: 300px;
float: left;
}
.splitter {
background-color: green;
width: 90px;
float: left;
}
.right {
background-color: blue;
width: 200px;
float: left;
}
/* wrapper for each examples */
section {
clear: both;
overflow: hidden;
margin: 1em;
}
/* different ways shown, usefull for testing only if you read about floats and dig a bit */
/* table */
.table .container {
display: table;
}
/* overflow */
.overflow .container {
overflow: hidden;
}
/* float */
.float .container {
float: left;
}
/* flex */
.flex .container {
display: flex;
}
/* inline-block */
.inline-block .container {
display: inline-block;
vertical-align: top;
}
/* last examples without floats */
/*no float & ie8 */
#table div {
float: none
}
#table #first-row,
#table > div {
display: table-row;
}
#table > div > div {
display: table-cell;
}
#table {
background-color: #333333;
width: 990px;
table-layout: fixed;
}
#left {
width: 300px;
}
#splitter {
width: 90px;
}
#right {
width: 200px;
}
#table > div > div {
background-color: red;
}
#table > div > div + div {
background-color: green;
}
#table > div > div + div + div {
background-color: blue;
}
#table:before {
display: table-caption;
width: 100%;
margin: 0;
}
#table > div:after {
content: "Notice there's a gap to fill here since cols do not cover the 990px";
display: table-cell;
}
<section class="your CSS :-: no BFC involved">
<div class="container">
<div class="left">A</div>
<div class="splitter">B</div>
<div class="right">C</div>
</div>
<div class="container">
<div class="left">D</div>
<div class="splitter">E</div>
<div class="right">F</div>
</div>
</section>
<section class="table">
<div class="container">
<div class="left">A</div>
<div class="splitter">B</div>
<div class="right">C</div>
</div>
<div class="container">
<div class="left">D</div>
<div class="splitter">E</div>
<div class="right">F</div>
</div>
</section>
<section class="overflow">
<div class="container">
<div class="left">A</div>
<div class="splitter">B</div>
<div class="right">C</div>
</div>
<div class="container">
<div class="left">D</div>
<div class="splitter">E</div>
<div class="right">F</div>
</div>
</section>
<section class="float">
<div class="container">
<div class="left">A</div>
<div class="splitter">B</div>
<div class="right">C</div>
</div>
<div class="container">
<div class="left">D</div>
<div class="splitter">E</div>
<div class="right">F</div>
</div>
</section>
<section class="flex">
<div class="container">
<div class="left">A</div>
<div class="splitter">B</div>
<div class="right">C</div>
</div>
<div class="container">
<div class="left">D</div>
<div class="splitter">E</div>
<div class="right">F</div>
</div>
</section>
<section class="inline-block">
<div class="container">
<div class="left">A</div>
<div class="splitter">B</div>
<div class="right">C</div>
</div>
<div class="container">
<div class="left">D</div>
<div class="splitter">E</div>
<div class="right">F</div>
</div>
</section>
<p>another way without float including IE8 ?</p>
<section id="table" class="table">
<div id="first-row">
<div id="left">A</div>
<div id="splitter">B</div>
<div id="right">C</div>
</div>
<div>
<div>D</div>
<div>E</div>
<div>F</div>
</div>
</section>
There could be more examples from the same chunks of code and floatting children.

Answer 2

Clear the floats in the container.
You have 3 simple ways to do that:
1. Float
#container {
clear: both;
}
2. Overflow
#container {
overflow: hidden;
}
3. Micro clearfix hack
Link

Answer 3

Here is what you want done bro..
this one is by using display:inline-block https://jsfiddle.net/p4domjrb/
this one is by using float:left https://jsfiddle.net/p4domjrb/1/
.container {
background-color: #333333;
width: 990px;
display: block;
position: relative;
}
.left {
background-color: red;
width: 300px;
display: inline-block;
margin-left: -4px;
}
.splitter {
background-color: green;
width: 90px;
display: inline-block;
margin-left: -4px;
}
.right {
background-color: blue;
width: 200px;
display: inline-block;
margin-left: -4px;
}
don't use id I suggest use class isntead because idis called only once.

Answer 4

<style>
.container{
background-color: #333333;
width:990px;
display:block;
clear:both;
}
#left{
background-color: red;
width:300px;
float:left;
}
#splitter{
background-color: green;
width:90px;
float:left;
}
#right{
background-color: blue;
width: 200px;
float:left;
}
</style>
<body>
<div class="container">
<div id="left">A</div>
<div id="splitter">B</div>
<div id="right">C</div>
</div>
<div class="container">
<div id="left">D</div>
<div id="splitter">E</div>
<div id="right">F</div>
</div>
</body>
result is