Proxima Nova with Sharp Sans in action on zendesk.com

Under the hood

.header-1 { font-family: "Sharp Sans", Arial, sans-serif; font-size: 45px; font-style: normal; font-weight: 700; letter-spacing: normal; line-height: 45px; text-transform: none; color: #FFFFFF; }
.content-1 { font-family: "Proxima Nova", Arial, sans-serif; font-size: 16px; font-style: normal; font-weight: 700; letter-spacing: normal; line-height: 24px; text-transform: none; color: #03363D; }