Fix the make note modal layout at dark theme

browser/main/modals/NewNoteModal.js

@@ -103,7 +103,7 @@ class NewNoteModal extends React.Component {
           <div styleName='title'>Make a Note</div>
         </div>
         <button styleName='closeButton' onClick={(e) => this.handleCloseButtonClick(e)}>
-          <div styleName='close-mark'>X</div>
+          <div styleName='close-mark'>×</div>
           <div styleName='close-text'>esc</div>
         </button>
 

browser/main/modals/NewNoteModal.styl

@@ -73,7 +73,7 @@ body[data-theme="dark"]
     color $ui-dark-text-color
     background-color transparent
     &:focus
-      colorPrimaryButton()
+      colorDarkPrimaryButton()
 
   .description
     color $ui-inactive-text-color

browser/styles/index.styl

@@ -95,6 +95,7 @@ colorPrimaryButton()
 $dark-primary-button-background = alpha(#3A404C, 80%)
 $dark-primary-button-background--hover = #3A404C
 $dark-primary-button-background--active = #3A404C
+
 colorDarkPrimaryButton()
   color white
   background-color $dark-primary-button-background