Although the provided solution is absolutely right, I think there is a different approach that could be interesting. Bootstrap does not provide alignment classes that depend on window size, but you can define them:
.text-justify-xs {
text-align: justify;
}
/* Small devices (tablets, 768px and up) */
@media (min-width: 768px) {
.text-justify-sm {
text-align: justify;
}
}
/* Medium devices (desktops, 992px and up) */
@media (min-width: 992px) {
.text-justify-md {
text-align: justify;
}
}
/* Large devices (large desktops, 1200px and up) */
@media (min-width: 1200px) {
.text-justify-lg {
text-align: justify;
}
}
Then, you could add this classes to your html elements:
<body class="text-justify-lg">
You can also create css rules for text-left-xx and text-right-xx.