I m working behind a web proxy. I have also set the web proxy. I m facing this error

Fatal error: { "message": "resource 'https://fonts.googleapis.com/css?family=Open+Sans:400,700|Raleway:400,700' gave this Error:\n Error: self signed certificate in certificate chain\n", "type": "File", "filename": "frontend/src/core/less/fonts.less", "index": 0, "line": 1, "column": 0, "callLine": null, "extract": [ null, "@import url('https://fonts.googleapis.com/css?family=Open+Sans:@{font-weight},@{font-weight-bold}|Raleway:@{font-weight},@{font-weight-bold}');", "" ] }