How can I center a div within another div? [duplicate]

Answer 1

This will work fine I think, though you might need to reset "top:200px;" according to your needs:

#main_content {
    top: 160px;
    left: 160px;
    width: 800px;
    min-height: 500px;
    height: auto;
    background-color: #2185C5;
    position: relative;
    border: 2px solid #CCCCCC;
}

#container {
    width: 100px;
    height: 20px;;
    margin: 0 auto;
    padding-top: 10px;
    position: relative;
    top: 200px;
    border: 2px solid #CCCCCC;
}

Answer 2

Another interesting way: fiddle

CSS

    .container {
        background: yellow;
        width: %100;
        display: flex;
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: center;
        align-items: center;
    }

    .centered-div {
        width: 80%;
        height: 190px;
        margin: 10px;
        padding: 5px;
        background: blue;
        color: white;
    }

HTML

    <div class="container">
        <div class="centered-div">
            <b>Enjoy</b>
        </div>
    </div>

Answer 3

It is because your width is set to auto. You have to specify the width for it to be visibly centered.

Your #container spans the whole width of the #main_content. That's why it seems not centered.

Answer 4

* {
  box-sizing: border-box;
}

#main_content {
  top: 160px;
  left: 160px;
  width: 800px;
  min-height: 500px;
  height: auto;
  background-color: #2185c5;
  position: relative;
}

#container {
  width: 50%;
  height: 50%;
  margin: auto;
  padding: 10px;
  position: absolute;
  border: 5px solid yellow;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
}

Answer 5

Technically, your inner DIV (#container) is centered horizontally. The reason you can't tell is because with the CSS width: auto property the inner DIV is expanding to the same width as its parent.

See this fiddle: http://jsfiddle.net/UZ4AE/

#container {
    width: 50px;
    height: auto;
    margin: 0 auto;
    padding: 10px;
    position: relative;
    background-color: red;
}

In this example, I simply set the width of #container to 50px and set the background to red so that you can see that it is centered.

I think the real question is "How do I center elements horizontally with CSS?" and the answer is (drum roll please): it depends!

I won't do a full rehash of the myriad ways to center things with CSS when W3Schools does it so nicely here: http://www.w3schools.com/css/css_align.asp but the basic idea is that for block level elements you simply specify the desired width and set the left and right margins to auto.

.center {
    margin-left: auto;
    margin-right: auto;
    width: 50px;
}

Please note: This answer only applies to block level elements! To position an inline element, you will need to use the text-align: center property on the first block parent.

Answer 6

You need to set the width of the container (auto won't work):

#container {
    width: 640px; /* Can be in percentage also. */
    height: auto;
    margin: 0 auto;
    padding: 10px;
    position: relative;
}

The CSS reference by MDN explains it all.

Check out these links:

• auto - CSS reference | MDN
• margin - CSS reference | MDN
• What is the meaning of auto value in a CSS property - Stack Overflow

In action at jsFiddle.