why this image is not full sized? - html

Question

I am trying to make this image full size but why some space is remaining right side
CSS/HTML
/* Header */
.header {
background: url('https://picsum.photos/1920/1080') center center no-repeat;
background-size: cover;
}
.header .header-content {
padding-top: 15.5rem;
text-align: left;
}
.header .text-container {
margin-top: 3rem;
margin-bottom: 0;
}
<link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.min.css" rel="stylesheet" />
<div id="content">
<!-- start of header -->
<header id="header" class="header">
<div class="header-content"> //here give an class of that image
<div class="container">
<div class="row">
<div class="col-lg-6">
<div class="text-container">
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</div>
<!-- end of text-container -->
</div>
<!-- end of col -->
<div class="col-lg-6">
<div class="image-container">
<img class="img-fluid" src="https://picsum.photos/1920/1088" alt="alternative">
</div>
<!-- end of image-container -->
</div>
<!-- end of col -->
</div>
<!-- end of row -->
</div>
<!-- end of container -->
</div>
<!-- end of header-content -->
</header>
<!-- end of header -->
</div>
I want to set this full image right side(question mark)
which place need correction

Answer 1

add the width and height to body and html in head.
html,body {
width:100%;
height:100%
}
.img-fluid{
width:100%
height:100%
}
.image-container{
width:<!--as you wish--> 20px;
height:<!--as you wish--> 20px;
}