/* cyrillic-ext */
@font-face {
  font-family: 'Montserrat';
  font-style: normal;
  font-weight: 400;
  src: local('Montserrat Regular'), local('Montserrat-Regular'), url(https://fonts.gstatic.com/s/montserrat/v12/rBHvpRWBkgyW99dXT88n7yEAvth_LlrfE80CYdSH47w.woff2) format('woff2');
  unicode-range: U+0460-052F, U+1C80-1C88, U+20B4, U+2DE0-2DFF, U+A640-A69F, U+FE2E-FE2F;
}
/* cyrillic */
@font-face {
  font-family: 'Montserrat';
  font-style: normal;
  font-weight: 400;
  src: local('Montserrat Regular'), local('Montserrat-Regular'), url(https://fonts.gstatic.com/s/montserrat/v12/NX1NravqaXESu9fFv7KuqiEAvth_LlrfE80CYdSH47w.woff2) format('woff2');
  unicode-range: U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
/* vietnamese */
@font-face {
  font-family: 'Montserrat';
  font-style: normal;
  font-weight: 400;
  src: local('Montserrat Regular'), local('Montserrat-Regular'), url(https://fonts.gstatic.com/s/montserrat/v12/SKK6Nusyv8QPNMtI4j9J2yEAvth_LlrfE80CYdSH47w.woff2) format('woff2');
  unicode-range: U+0102-0103, U+0110-0111, U+1EA0-1EF9, U+20AB;
}
/* latin-ext */
@font-face {
  font-family: 'Montserrat';
  font-style: normal;
  font-weight: 400;
  src: local('Montserrat Regular'), local('Montserrat-Regular'), url(https://fonts.gstatic.com/s/montserrat/v12/gFXtEMCp1m_YzxsBpKl68iEAvth_LlrfE80CYdSH47w.woff2) format('woff2');
  unicode-range: U+0100-024F, U+0259, U+1E00-1EFF, U+20A0-20AB, U+20AD-20CF, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Montserrat';
  font-style: normal;
  font-weight: 400;
  src: local('Montserrat Regular'), local('Montserrat-Regular'), url(https://fonts.gstatic.com/s/montserrat/v12/zhcz-_WihjSQC0oHJ9TCYPk_vArhqVIZ0nv9q090hN8.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2212, U+2215;
}

WebClient client = new WebClient();
string downloadString = client.DownloadString("https://fonts.googleapis.com/css?family=Montserrat");

@font-face {
  font-family: 'Montserrat';
  font-style: normal;
  font-weight: 400;
  src: local('Montserrat Regular'), local('Montserrat-Regular'), url(https://fonts.gstatic.com/s/montserrat/v12/zhcz-_WihjSQC0oHJ9TCYC3USBnSvpkopQaUR-2r7iU.ttf) format('truetype');
}