The “Strong Families” section isn’t responsive because you added a width to it in your Custom CSS on line 4476.
.home-feature-bg-alt .wrap {
margin: 0 auto;
overflow: hidden;
padding: 120px 0 80px;
width: 1140px;
}
You can remove that width as it’s not needed since there is already code that handles that section in your css.
The other sections are responsive because the responsive code/width kicks in at line 4095 –
.site-header,
.nav-primary .wrap,
.nav-secondary .wrap,
.slider .wrap,
.welcome .wrap,
.home-feature-bg .wrap,
.home-feature-bg-alt .wrap,
.home-feature-bg-dark .wrap,
.footer-widgets .wrap {
width: 90%;
}
This part – .home-feature-bg-alt .wrap,
is what handles that particular section, and I’m guessing since you had it last (after the code above) your css gives it priority and uses the width you added rather than what’s already available in your responsive css. So just delete that width that you added on line 4476 – width: 1140px;
and it should work fine.