Fix rendering docsite on smartphone/tablets (#36675)

docs/docsite/_themes/sphinx_rtd_theme/static/css/theme.css

@@ -1686,7 +1686,7 @@ code.code-large,.rst-content tt.code-large{font-size:90%}
 .wy-nav-top a{color:#fff;font-weight:bold}
 .wy-nav-top img{margin-right:12px;height:45px;width:45px;background-color:#2980B9;padding:5px;border-radius:100%}
 .wy-nav-top i{font-size:30px;float:left;cursor:pointer;padding-top:inherit}
-.wy-nav-content-wrap{margin-top: 30px;margin-left: 300px;width: calc(100% - 310px);float:left;background:#fcfcfc;min-height:100%}
+.wy-nav-content-wrap{margin-top: 30px;margin-left: 300px;width: 100%;float:left;background:#fcfcfc;min-height:100%}
 .wy-nav-content{padding:1.618em 3.236em;height:100%;margin:auto;overflow-x: hidden;overflow-y: scroll}
 .wy-body-mask{position:fixed;width:100%;height:100%;background:rgba(0,0,0,0.2);display:none;z-index:499}
 .wy-body-mask.on{display:block}