SCSS用ブレイクポイント
$breakpoint: (
'PC': 'screen and (min-width: 768px)',
'TAB': 'screen and (min-width: 768px) and (max-width: 1366px)',
'SP': 'screen and (max-width: 767px)'
);
@mixin mq($bp: PC) {
@media #{map-get($breakpoint, $bp)} {
@content;
}
}