Buttons

text-decoration: none;
background-image: none;
background: #1979c3;
border: 1px solid #1979c3;
color: #ffffff;
display: inline-block;
font-family: 'Open Sans', 'Helvetica Neue', Helvetica, Arial, sans-serif;
font-weight: 600;
margin: 0 10px 10px 0;
box-sizing: border-box;
vertical-align: middle;
line-height: 2.2rem;
padding: 14px 17px;
font-size: 1.8rem;
border-radius: 3px;
box-shadow: none;

Hover and Focus/Active/Touch:

background: #006bb4;
border: 1px solid #006bb4;

Disabled:

opacity: .5;
cursor: default;
pointer-events: none;

text-decoration: none;
background-image: none;
background: #eeeeee;
border: 1px solid #cccccc;
color: #333333;
display: inline-block;
font-family: 'Open Sans', 'Helvetica Neue', Helvetica, Arial, sans-serif;
font-weight: 600;
margin: 0 10px 10px 0;
box-sizing: border-box;
vertical-align: middle;
line-height: 2.2rem;
padding: 14px 17px;
font-size: 1.8rem;
border-radius: 3px;
box-shadow: none;

Hover and Focus/Active/Touch:

background: #e1e1e1;
border: 1px solid #ccc;

Disabled:

opacity: .5;
cursor: default;
pointer-events: none;

font-size: 1.8rem;
font-family: 'Open Sans', 'Helvetica Neue', Helvetica, Arial, sans-serif;
line-height: 1.42857143;
margin: 0 10px 10px 0;
padding: 14px 17px;
color: #006bb4;
text-decoration: none;
background: none;
border: 0;
font-weight: 600;
box-shadow: none;
box-sizing: border-box;
display: inline-block;

Hover:

text-decoration: underline;

Active:

color: #ff5501;
text-decoration: underline;

Disabled:

opacity: .5;
cursor: default;
pointer-events: none;