Please use the custom CSS(“Appearance > Customize: Additional CSS”) to set fixed width for the 70% width of fullwidth:
.fullwrap-inn-width-70, .fullwrap-inn-width-70.row {padding-left: 20px; padding-right: 20px;}
@media (max-width: 767px) {
.fullwrap-inn-width-70, .fullwrap-inn-width-70.row { width: 100%; }
}
@media (min-width: 768px) {
.fullwrap-inn-width-70, .fullwrap-inn-width-70.row { width: 750px; }
}
@media (min-width: 992px) {
.fullwrap-inn-width-70, .fullwrap-inn-width-70.row { width: 970px; }
}
@media(min-width:1200px) {
.fullwrap-inn-width-70, .fullwrap-inn-width-70.row { width: 970px; }
}
.
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