diff --git a/examples/scripts/plugins/jspsych-categorize-animation.js b/examples/scripts/plugins/jspsych-categorize-animation.js
index e6344ef4..cb410df6 100644
--- a/examples/scripts/plugins/jspsych-categorize-animation.js
+++ b/examples/scripts/plugins/jspsych-categorize-animation.js
@@ -37,7 +37,7 @@
                 trials[i].stims = params.stimuli[i];
                 trials[i].reps = params.reps || 1;
                 trials[i].key_answer = params.key_answer[i];
-                trials[i].text_answer = params.text_answer[i] || "";
+                trials[i].text_answer = (typeof params.text_answer === 'undefined') ? "" : params.text_answer[i];
                 trials[i].choices = params.choices;
                 trials[i].correct_text = params.correct_text || "Correct.";
                 trials[i].incorrect_text = params.incorrect_text || "Wrong.";
diff --git a/stylesheets/pygment_trac.css b/stylesheets/pygment_trac.css
deleted file mode 100644
index c6a6452d..00000000
--- a/stylesheets/pygment_trac.css
+++ /dev/null
@@ -1,69 +0,0 @@
-.highlight  { background: #ffffff; }
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-.highlight .gt { color: #aa0000 } /* Generic.Traceback */
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-.highlight .vi { color: #008080 } /* Name.Variable.Instance */
-.highlight .il { color: #009999 } /* Literal.Number.Integer.Long */
-
-.type-csharp .highlight .k { color: #0000FF }
-.type-csharp .highlight .kt { color: #0000FF }
-.type-csharp .highlight .nf { color: #000000; font-weight: normal }
-.type-csharp .highlight .nc { color: #2B91AF }
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-.type-csharp .highlight .sc { color: #A31515 }
diff --git a/stylesheets/styles.css b/stylesheets/styles.css
deleted file mode 100644
index dacf2e18..00000000
--- a/stylesheets/styles.css
+++ /dev/null
@@ -1,255 +0,0 @@
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-  font-weight:400;
-  text-decoration:none;
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-
-a small {
-  font-size:11px;
-  color:#777;
-  margin-top:-0.6em;
-  display:block;
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-
-.wrapper {
-  width:860px;
-  margin:0 auto;
-}
-
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-  border-left:1px solid #e5e5e5;
-  margin:0;
-  padding:0 0 0 20px;
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-  text-align:center;
-  padding-top:6px;
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-  width:88px;
-  border-left:1px solid #fff;
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