Add skewer-css-clear-all command (#42).

skewer-css.el

@@ -106,14 +106,20 @@
   (interactive)
   (skewer-css (buffer-substring-no-properties (point-min) (point-max))))
 
+(defun skewer-css-clear-all ()
+  "Remove *all* Skewer-added styles from the document."
+  (interactive)
+  (skewer-eval nil nil :type "cssClearAll"))
+
 ;; Minor mode definition
 
 (defvar skewer-css-mode-map
   (let ((map (make-sparse-keymap)))
     (prog1 map
       (define-key map (kbd "C-x C-e") 'skewer-css-eval-current-declaration)
       (define-key map (kbd "C-M-x") 'skewer-css-eval-current-rule)
-      (define-key map (kbd "C-c C-k") 'skewer-css-eval-buffer)))
+      (define-key map (kbd "C-c C-k") 'skewer-css-eval-buffer)
+      (define-key map (kbd "C-c C-c") 'skewer-css-clear-all)))
   "Keymap for skewer-css-mode.")
 
 ;;;###autoload

skewer.js

@@ -168,6 +168,7 @@ skewer.fn.ping = function(request) {
 skewer.fn.css = function(request) {
     var style = document.createElement('style');
     style.type = 'text/css';
+    style.className = 'skewer';
     if (style.styleSheet) { // < IE9
         style.styleSheet.cssText = request.eval;
     } else {
@@ -177,6 +178,17 @@ skewer.fn.css = function(request) {
     return {};
 };
 
+/**
+ * Remove all of Skewer's style tags from the document.
+ */
+skewer.fn.cssClearAll = function(request) {
+    var styles = document.body.querySelectorAll('style.skewer');
+    for (var i = 0; i < styles.length; i++) {
+        styles[i].parentNode.removeChild(styles[i]);
+    }
+    return {};
+};
+
 /**
  * HTML evaluator, appends or replaces a selection with given HTML.
  */