Why margin is not respected in this case? - html

Question

I can't figure out why a margin is not respected when I resize to mobile view. If you resize the window, left margin is respected, however, right margin is not respected.
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
.banner-container {
position: relative;
}
.banner-image {
height: 200px;
width: 100%;
background-color: rebeccapurple;
background-position: center;
background-size: cover;
background-repeat: no-repeat;
}
.banner-text {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
max-width: 560px;
width: 100%;
background-color: rgba(255, 255, 255, 0.5);
text-align: center;
font-size: 32px;
padding: 24px 0;
margin: 0 10px;
}
#media screen and (max-width: 768px) {
.banner-text {
font-size: 24px;
}
}
<div class="banner-container">
<div class="banner-image"></div>
<span class="banner-text">Candidate Membership</span>
</div>
I'd appreciate if someone could explain what I'm doing wrong. Thanks.

Answer 1

The margin is there, but it is added to the 100% width you defined. So the element's width including margins goes beyond the container width.

Answer 2

.banner-text in media width : 80%
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
.banner-container {
position: relative;
}
.banner-image {
height: 200px;
width: 100%;
background-color: rebeccapurple;
background-position: center;
background-size: cover;
background-repeat: no-repeat;
}
.banner-text {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
max-width: 560px;
width: 100%;
background-color: rgba(255, 255, 255, 0.5);
text-align: center;
font-size: 32px;
padding: 24px 0;
margin: 0 10px;
}
#media screen and (max-width: 768px) {
.banner-text {
font-size: 24px;
}
.banner-text{
width: 80%;
}
}
<div class="banner-container">
<div class="banner-image"></div>
<span class="banner-text">Candidate Membership</span>
</div>