There is no "mobile" layout - it is responsive to screen width.
If you want the array questions in a vertical block layout for all screens widths, extend your theme and add something like this to the end of the custom.css file:
Code:
@media only screen and (max-width: 3000px) {
table.ls-answers,table.ls-answers thead,table.ls-answers tbody,table.ls-answers th,table.ls-answers td,table.ls-answers tr {display: block;}
.dir-ltr table.ls-answers,.dir-ltr table.ls-answers thead,.dir-ltr table.ls-answers tbody,.dir-ltr table.ls-answers th,.dir-ltr table.ls-answers td,table.ls-answers tr {text-align:left;}
.dir-rtl table.ls-answers,.dir-rtl table.ls-answers thead,.dir-rtl table.ls-answers tbody,.dir-rtl table.ls-answers th,.dir-rtl table.ls-answers td,table.ls-answers tr {text-align:right;}
table.ls-answers thead{display:none} /* We don't need it for accessibility : we already have the label */
table.ls-answers tbody td{text-align:left;}
table.ls-answers .information-item:empty{display:none}
.dir-rtl table.ls-answers tbody td{text-align:right;}
.ls-answers td.radio-item,.ls-answers td.checkbox-item{padding: 4px;}
.dir-ltr .ls-answers td.radio-item,.dir-ltr .ls-answers td.checkbox-item{padding-left: 24px;padding-right: 4px;}
.dir-rtl .ls-answers td.radio-item,.dir-rtl .ls-answers td.checkbox-item{padding-right: 24px;padding-left: 4px;}
table.ls-answers tbody .control-label{text-align:left}
.dir-rtl table.ls-answers tbody .control-label{text-align:right}
table.ls-answers .answertextright{text-align:right}
.dir-rtl table.ls-answers .answertextright{text-align:left}
/* Show the label */
table.ls-answers .ls-label-xs-visibility
{
display:block;
position:relative;
width: auto;
height: auto;
overflow:initial;
white-space: normal;
}
.dir-ltr table.ls-answers .ls-label-xs-visibility{left:auto;}
.dir-rtl table.ls-answers .ls-label-xs-visibility{right:auto;}
table.ls-answers .radio-item .ls-label-xs-visibility,table.ls-answers .checkbox-item .ls-label-xs-visibility{
line-height: initial;
text-indent: initial;
}
.dir-ltr table.ls-answers .radio-item .ls-label-xs-visibility,.dir-ltr table.ls-answers .checkbox-item .ls-label-xs-visibility{margin-left:0;}
.dir-rtl table.ls-answers .radio-item .ls-label-xs-visibility,.dir-rtl table.ls-answers .checkbox-item .ls-label-xs-visibility{margin-right:0;}
table.ls-answers .ls-label-xs-visibility > *
{
position:relative;
top:auto;
width:auto;
height:auto;
overflow:auto;
}
.dir-ltr table.ls-answers .ls-label-xs-visibility > * {left:auto;}
.dir-rtl table.ls-answers .ls-label-xs-visibility > * {right:auto;}
.dir-rtl table.ls-answers .answers-list p[dir=rtl] {left:0;text-align:right;}
.dir-ltr table.ls-answers .radio-item label.ls-label-xs-visibility::before,.dir-ltr table.ls-answers .checkbox-item label.ls-label-xs-visibility::before {margin-left:-20px;}
.dir-rtl table.ls-answers .radio-item label.ls-label-xs-visibility::before,.dir-rtl table.ls-answers .checkbox-item label.ls-label-xs-visibility::before {margin-right:-20px;}
.dir-ltr table.ls-answers .radio-item label.ls-label-xs-visibility::after,.dir-ltr table.ls-answers .checkbox-item label.ls-label-xs-visibility::after {margin-left:-20px;}
.dir-rtl table.ls-answers .radio-item label.ls-label-xs-visibility::after,.dir-rtl table.ls-answers .checkbox-item label.ls-label-xs-visibility::after {margin-right:-20px;}
table.ls-answers > tbody > tr:hover {
background-color: transparent;
}
/* bs fix */
table.ls-answers td.visible-xs,table.ls-answers th.visible-xs{display:block !important}
}
