There's another approach to responsive font sizes - using rem units.
html {
/* Base font size */
font-size: 16px;
}
h1 {
font-size: 1.5rem;
}
h2 {
font-size: 1.2rem;
}
Later in media queries, you can adjust all fonts sizes by changing the base font size:
@media screen and (max-width: 767px) {
html {
/* Reducing base font size will reduce all rem sizes */
font-size: 13px;
}
/* You can reduce font sizes manually as well */
h1 {
font-size: 1.2rem;
}
h2 {
font-size: 1.0rem;
}
}
To make this work in Internet Explorer 7 and Internet Explorer 8 you will have to add a fallback with px units:
h1 {
font-size: 18px;
font-size: 1.125rem;
}
If you're developing with Less, you can create a mixin that will do the math for you.
Rem units support - http://caniuse.com/#feat=rem