垂直对齐Flexbox项，而不会导致项之间的幻影空白

Question

The problem I'm facing here is that when using Flexbox's " flex-wrap: wrap ", it seems to cause extra white space beneath the div .

My setup is like this (class names to clarify the use of the div):

<div class="viewheight-background">

    <div class="header"></div>
    <div class="vertically-centered-text"></div>

</div>

My css is pretty straight forward:

html, body{
    height: 100%;
}

.viewheight-background {
    min-height: 100%; /* To ensure a section of 100% screen height, could be done with 'vh' */
    background-size: cover;

    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
}

.vertically-centered-text {
    align-self: center;
}

The vertically-centered-text is inside a div because I am dealing with a main heading and some subtext.

If I take away " align-self: center ", the flex-items wrap just fine except for one thing. There seems to be some kind of phantom white-space which I can't identify. This causes " align-self: center " to be lower than the center of the div it should be centered in.

Any ideas?

(If I'm being too vague, please let me know and i'll clarify)

EDIT:

Fiddle for reference. Forgot to add html, body {height: 100%;}

Answer 1

Finally found a decent solution.

It appears that:

float, clear and vertical-align have no effect on a flex item.

So I Found out the issue was with with your:

align-self: center;

on your second flex item.

So your css should be edited to:

.vertically-centered-text {
    /*align-self: center;*/
    background-color:blue;
    display: -webkit-flexbox;
    display: -ms-flexbox;
    display: -webkit-flex;
    display: flex;
    -webkit-flex-align: center;
    -ms-flex-align: center;
    -webkit-align-items: center;
    align-items: center;
    text-align: center;
}

As shown in this LIVE DEMO or run this snippet (in full page view):

 html, body { height: 100%; } .viewheight-background { min-height: 100%; /* To ensure a section of 100% screen height, could be done with 'vh' */ background-size: cover; display: flex; flex-direction: row; flex-wrap: wrap; } .vertically-centered-text { /*align-self: center;*/ background-color: blue; display: -webkit-flexbox; display: -ms-flexbox; display: -webkit-flex; display: flex; -webkit-flex-align: center; -ms-flex-align: center; -webkit-align-items: center; align-items: center; text-align: center; } .header { background-color: red; } 

 <div class="viewheight-background"> <div class="header">Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum</div> <div class="vertically-centered-text">Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</div> </div>