Swap Helvetica out for San Francisco, as God and Jony Ive intended.

quellvetica.css

/*
**
**            ,ad8888ba,                          88 88                                88
**           d8"'    `"8b                         88 88                          ,d    ""
**          d8'        `8b                        88 88                          88
**          88          88 88       88  ,adPPYba, 88 88 8b       d8  ,adPPYba, MM88MMM 88  ,adPPYba, ,adPPYYba,
**          88          88 88       88 a8P_____88 88 88 `8b     d8' a8P_____88   88    88 a8"     "" ""     `Y8
**          Y8,    "88,,8P 88       88 8PP""""""" 88 88  `8b   d8'  8PP"""""""   88    88 8b         ,adPPPPP88
**           Y8a.    Y88P  "8a,   ,a88 "8b,   ,aa 88 88   `8b,d8'   "8b,   ,aa   88,   88 "8a,   ,aa 88,    ,88
**            `"Y8888Y"Y8a  `"YbbdP'Y8  `"Ybbd8"' 88 88     "8"      `"Ybbd8"'   "Y888 88  `"Ybbd8"' `"8bbdP"Y8
**
*/

@font-face {
  font-family: 'Helvetica Neue';
  font-style: normal;
  font-weight: 300;
  src: local('SFProText-Light');
}

@font-face {
  font-family: 'Helvetica Neue';
  font-style: italic;
  font-weight: 300;
  src: local('SFProText-LightItalic');
}

@font-face {
  font-family: 'Helvetica Neue';
  font-style: normal;
  font-weight: 400;
  src: local('SFProText-Regular');
}

@font-face {
  font-family: 'Helvetica Neue';
  font-style: italic;
  font-weight: 400;
  src: local('SFProText-Italic');
}

@font-face {
  font-family: 'Helvetica Neue';
  font-style: normal;
  font-weight: 700;
  src: local('SFProText-Bold');
}

@font-face {
  font-family: 'Helvetica Neue';
  font-style: italic;
  font-weight: 700;
  src: local('SFProText-BoldItalic');
}