Bootstrap: 100% sceen width child element inside .container with no multiple .container elements, no javascript.

style.css

.hr-div {
    padding: 10px;
}
    .hr-div div {
        border-top: 1px solid #f68e92;
        position: absolute;
        width: 100vw;
        left: 0;
    }

@media (min-width: 576px) {
    .hr-div div {
        left: calc(510px/2 - 50vw);
    }
}

@media (min-width: 768px) {
    .hr-div div {
        left: calc(690px/2 - 50vw);
    }
}

@media (min-width: 992px) {
    .hr-div div {
        left: calc(930px/2 - 50vw);
    }
}

@media (min-width: 1200px) {
    .hr-div div {
        left: calc(1110px/2 - 50vw);
    }
}

The reason are inside _grid.scss we have
`
@media (min-width: 576px) {
.container {
width: 540px;
max-width: 100%;
}
}

@media (min-width: 768px) {
.container {
width: 720px;
max-width: 100%;
}
}

@media (min-width: 992px) {
.container {
width: 960px;
max-width: 100%;
}
}

@media (min-width: 1200px) {
.container {
width: 1140px;
max-width: 100%;
}
}`
and the .container have padding left and right 15px each. So for 1200px we have child width 1110px and so on.

markup

    <div class="hr-div">
        <div></div>
    </div>