Text Overlap Video tag CSS - html

Question

I'm not sure as to why when I drag my browser around my text and video overlap. I want to prevent this:
Here is a jsfiddle example:
https://jsfiddle.net/liondancer/m3xug7vo/
example:
Here is the CSS regarding the particular page:
.wrapper {
width: 950px;
margin: auto; /* Centering blocks */
/*position: relative;
display: block;*/
}
.index {
}
.video-container {
position: relative;
min-width: 100%;
min-height: 100%;
/*width: auto;
height: auto;*/
z-index: -100;
background: no-repeat;
/*background-size: cover;*/
display: block;
width: 100vw;
height: 100vh;
object-fit: cover;
}
.title-area {
height: 100%;
width: 100%;
vertical-align: middle;
.container {
width: 100%;
padding-left: 20px;
padding-right: 20px;
margin: 0 auto;
position: relative;
}
}
.index-aboutus {
position: relative;
min-width: 100%;
min-height: 100%;
height: 100%;
display: block;
}
.index-ourwork {
position: relative;
min-width: 100%;
min-height: 100%;
height: 100%;
}
.index-instructors {
position: relative;
min-width: 100%;
min-height: 100%;
height: 100%;
}
The HTML:

Answer 1

The video container is using a height of 100vh, there is one thing you have to think of:
The viewport-percentage lengths are relative to the size of the
initial containing block. When the height or width of the initial
containing block is changed, they are scaled accordingly. However,
when the value of overflow on the root element is auto, any scroll
bars are assumed not to exist.
See http://www.w3.org/TR/css3-values/#viewport-relative-lengths
An easy way to fix this would be to add a class to the parent div of video-container and add a property to set it to overflow: hidden;
It would look like the following:
.video-containerParent {
overflow: hidden;
}
Please see the following jsFiddle for an example:
https://jsfiddle.net/m3xug7vo/1/
The following site has an interesting article about viewport units:
https://web-design-weekly.com/2014/11/18/viewport-units-vw-vh-vmin-vmax/