diff --git a/IPython/html/static/base/less/flexbox.less b/IPython/html/static/base/less/flexbox.less
index 60874fc..e37e4be 100644
--- a/IPython/html/static/base/less/flexbox.less
+++ b/IPython/html/static/base/less/flexbox.less
@@ -80,6 +80,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     flex: none;
 }
 
+.hbox.reverse,
+.vbox.reverse,
 .reverse {
     /* Old browsers */
     -webkit-box-direction: reverse;
@@ -90,6 +92,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     flex-direction: row-reverse;
 }
 
+.hbox.box-flex0,
+.vbox.box-flex0,
 .box-flex0 {
     /* Old browsers */
     -webkit-box-flex: 0;
@@ -101,6 +105,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     width: auto;
 }
 
+.hbox.box-flex1,
+.vbox.box-flex1,
 .box-flex1 {
     /* Old browsers */
     -webkit-box-flex: 1;
@@ -111,11 +117,15 @@ Browsers not listed, including Safari, are supported via the styling under the
     flex: 1;
 }
 
+.hbox.box-flex,
+.vbox.box-flex,
 .box-flex {
     /* Old browsers */
     .box-flex1();
 }
 
+.hbox.box-flex2,
+.vbox.box-flex2,
 .box-flex2 {
     /* Old browsers */
     -webkit-box-flex: 2;
@@ -140,6 +150,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     box-flex-group: 2;
 }
 
+.hbox.start, 
+.vbox.start,
 .start {
     /* Old browsers */
     -webkit-box-pack: start;
@@ -150,6 +162,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     justify-content: flex-start;
 }
 
+.hbox.end, 
+.vbox.end,
 .end {
     /* Old browsers */
     -webkit-box-pack: end;
@@ -160,6 +174,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     justify-content: flex-end;
 }
 
+.hbox.center, 
+.vbox.center,
 .center {
     /* Old browsers */
     -webkit-box-pack: center;
@@ -170,6 +186,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     justify-content: center;
 }
 
+.hbox.align-start, 
+.vbox.align-start,
 .align-start {
     /* Old browsers */
     -webkit-box-align: start;
@@ -180,6 +198,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     align-items: flex-start;
 }
 
+.hbox.align-end, 
+.vbox.align-end,
 .align-end {
     /* Old browsers */
     -webkit-box-align: end;
@@ -190,6 +210,8 @@ Browsers not listed, including Safari, are supported via the styling under the
     align-items: flex-end;
 }
 
+.hbox.align-center, 
+.vbox.align-center,
 .align-center {
     /* Old browsers */
     -webkit-box-align: center;
diff --git a/IPython/html/static/style/ipython.min.css b/IPython/html/static/style/ipython.min.css
index 1029e0c..b608f69 100644
--- a/IPython/html/static/style/ipython.min.css
+++ b/IPython/html/static/style/ipython.min.css
@@ -9,19 +9,19 @@ code{color:#000}
 .hbox>*{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none}
 .vbox{display:-webkit-box;-webkit-box-orient:vertical;-webkit-box-align:stretch;display:-moz-box;-moz-box-orient:vertical;-moz-box-align:stretch;display:box;box-orient:vertical;box-align:stretch;width:100%;display:flex;flex-direction:column;align-items:stretch}
 .vbox>*{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none}
-.reverse{-webkit-box-direction:reverse;-moz-box-direction:reverse;box-direction:reverse;flex-direction:row-reverse}
-.box-flex0{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none;width:auto}
-.box-flex1{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
-.box-flex{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
-.box-flex2{-webkit-box-flex:2;-moz-box-flex:2;box-flex:2;flex:2}
+.hbox.reverse,.vbox.reverse,.reverse{-webkit-box-direction:reverse;-moz-box-direction:reverse;box-direction:reverse;flex-direction:row-reverse}
+.hbox.box-flex0,.vbox.box-flex0,.box-flex0{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none;width:auto}
+.hbox.box-flex1,.vbox.box-flex1,.box-flex1{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
+.hbox.box-flex,.vbox.box-flex,.box-flex{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
+.hbox.box-flex2,.vbox.box-flex2,.box-flex2{-webkit-box-flex:2;-moz-box-flex:2;box-flex:2;flex:2}
 .box-group1{-webkit-box-flex-group:1;-moz-box-flex-group:1;box-flex-group:1}
 .box-group2{-webkit-box-flex-group:2;-moz-box-flex-group:2;box-flex-group:2}
-.start{-webkit-box-pack:start;-moz-box-pack:start;box-pack:start;justify-content:flex-start}
-.end{-webkit-box-pack:end;-moz-box-pack:end;box-pack:end;justify-content:flex-end}
-.center{-webkit-box-pack:center;-moz-box-pack:center;box-pack:center;justify-content:center}
-.align-start{-webkit-box-align:start;-moz-box-align:start;box-align:start;align-items:flex-start}
-.align-end{-webkit-box-align:end;-moz-box-align:end;box-align:end;align-items:flex-end}
-.align-center{-webkit-box-align:center;-moz-box-align:center;box-align:center;align-items:center}
+.hbox.start,.vbox.start,.start{-webkit-box-pack:start;-moz-box-pack:start;box-pack:start;justify-content:flex-start}
+.hbox.end,.vbox.end,.end{-webkit-box-pack:end;-moz-box-pack:end;box-pack:end;justify-content:flex-end}
+.hbox.center,.vbox.center,.center{-webkit-box-pack:center;-moz-box-pack:center;box-pack:center;justify-content:center}
+.hbox.align-start,.vbox.align-start,.align-start{-webkit-box-align:start;-moz-box-align:start;box-align:start;align-items:flex-start}
+.hbox.align-end,.vbox.align-end,.align-end{-webkit-box-align:end;-moz-box-align:end;box-align:end;align-items:flex-end}
+.hbox.align-center,.vbox.align-center,.align-center{-webkit-box-align:center;-moz-box-align:center;box-align:center;align-items:center}
 div.error{margin:2em;text-align:center}
 div.error>h1{font-size:500%;line-height:normal}
 div.error>p{font-size:200%;line-height:normal}
diff --git a/IPython/html/static/style/style.min.css b/IPython/html/static/style/style.min.css
index 33cbbc8..b1796b9 100644
--- a/IPython/html/static/style/style.min.css
+++ b/IPython/html/static/style/style.min.css
@@ -1272,19 +1272,19 @@ code{color:#000}
 .hbox>*{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none}
 .vbox{display:-webkit-box;-webkit-box-orient:vertical;-webkit-box-align:stretch;display:-moz-box;-moz-box-orient:vertical;-moz-box-align:stretch;display:box;box-orient:vertical;box-align:stretch;width:100%;display:flex;flex-direction:column;align-items:stretch}
 .vbox>*{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none}
-.reverse{-webkit-box-direction:reverse;-moz-box-direction:reverse;box-direction:reverse;flex-direction:row-reverse}
-.box-flex0{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none;width:auto}
-.box-flex1{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
-.box-flex{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
-.box-flex2{-webkit-box-flex:2;-moz-box-flex:2;box-flex:2;flex:2}
+.hbox.reverse,.vbox.reverse,.reverse{-webkit-box-direction:reverse;-moz-box-direction:reverse;box-direction:reverse;flex-direction:row-reverse}
+.hbox.box-flex0,.vbox.box-flex0,.box-flex0{-webkit-box-flex:0;-moz-box-flex:0;box-flex:0;flex:none;width:auto}
+.hbox.box-flex1,.vbox.box-flex1,.box-flex1{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
+.hbox.box-flex,.vbox.box-flex,.box-flex{-webkit-box-flex:1;-moz-box-flex:1;box-flex:1;flex:1}
+.hbox.box-flex2,.vbox.box-flex2,.box-flex2{-webkit-box-flex:2;-moz-box-flex:2;box-flex:2;flex:2}
 .box-group1{-webkit-box-flex-group:1;-moz-box-flex-group:1;box-flex-group:1}
 .box-group2{-webkit-box-flex-group:2;-moz-box-flex-group:2;box-flex-group:2}
-.start{-webkit-box-pack:start;-moz-box-pack:start;box-pack:start;justify-content:flex-start}
-.end{-webkit-box-pack:end;-moz-box-pack:end;box-pack:end;justify-content:flex-end}
-.center{-webkit-box-pack:center;-moz-box-pack:center;box-pack:center;justify-content:center}
-.align-start{-webkit-box-align:start;-moz-box-align:start;box-align:start;align-items:flex-start}
-.align-end{-webkit-box-align:end;-moz-box-align:end;box-align:end;align-items:flex-end}
-.align-center{-webkit-box-align:center;-moz-box-align:center;box-align:center;align-items:center}
+.hbox.start,.vbox.start,.start{-webkit-box-pack:start;-moz-box-pack:start;box-pack:start;justify-content:flex-start}
+.hbox.end,.vbox.end,.end{-webkit-box-pack:end;-moz-box-pack:end;box-pack:end;justify-content:flex-end}
+.hbox.center,.vbox.center,.center{-webkit-box-pack:center;-moz-box-pack:center;box-pack:center;justify-content:center}
+.hbox.align-start,.vbox.align-start,.align-start{-webkit-box-align:start;-moz-box-align:start;box-align:start;align-items:flex-start}
+.hbox.align-end,.vbox.align-end,.align-end{-webkit-box-align:end;-moz-box-align:end;box-align:end;align-items:flex-end}
+.hbox.align-center,.vbox.align-center,.align-center{-webkit-box-align:center;-moz-box-align:center;box-align:center;align-items:center}
 div.error{margin:2em;text-align:center}
 div.error>h1{font-size:500%;line-height:normal}
 div.error>p{font-size:200%;line-height:normal}