diff --git a/css/theme/beige.css b/css/theme/beige.css
index 5bbda4b9..7f71dd95 100644
--- a/css/theme/beige.css
+++ b/css/theme/beige.css
@@ -29,6 +29,11 @@ body {
   background: rgba(79, 64, 28, 0.99);
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: rgba(79, 64, 28, 0.99);
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/black.css b/css/theme/black.css
index 511fa798..9228c46a 100644
--- a/css/theme/black.css
+++ b/css/theme/black.css
@@ -25,6 +25,11 @@ body {
   background: #bee4fd;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #bee4fd;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/blood.css b/css/theme/blood.css
index 6fe3d67b..2da8d683 100644
--- a/css/theme/blood.css
+++ b/css/theme/blood.css
@@ -28,6 +28,11 @@ body {
   background: #a23;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #a23;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/league.css b/css/theme/league.css
index 03c44ce0..aa5bee5c 100644
--- a/css/theme/league.css
+++ b/css/theme/league.css
@@ -31,6 +31,11 @@ body {
   background: #FF5E99;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #FF5E99;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/moon.css b/css/theme/moon.css
index 5e5d6e4c..5cb11765 100644
--- a/css/theme/moon.css
+++ b/css/theme/moon.css
@@ -29,6 +29,11 @@ body {
   background: #d33682;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #d33682;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/night.css b/css/theme/night.css
index a439cdcf..cf2c7a7e 100644
--- a/css/theme/night.css
+++ b/css/theme/night.css
@@ -23,6 +23,11 @@ body {
   background: #e7ad52;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #e7ad52;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/serif.css b/css/theme/serif.css
index 40ccb397..bbb9f7eb 100644
--- a/css/theme/serif.css
+++ b/css/theme/serif.css
@@ -25,6 +25,11 @@ body {
   background: #26351C;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #26351C;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/simple.css b/css/theme/simple.css
index b17fa5cd..33809ec5 100644
--- a/css/theme/simple.css
+++ b/css/theme/simple.css
@@ -25,6 +25,11 @@ body {
   background: rgba(0, 0, 0, 0.99);
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: rgba(0, 0, 0, 0.99);
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/sky.css b/css/theme/sky.css
index 99f1cfdf..202ade8c 100644
--- a/css/theme/sky.css
+++ b/css/theme/sky.css
@@ -32,6 +32,11 @@ body {
   background: #134674;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #134674;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/solarized.css b/css/theme/solarized.css
index b4d4d4bd..44771dca 100644
--- a/css/theme/solarized.css
+++ b/css/theme/solarized.css
@@ -29,6 +29,11 @@ body {
   background: #d33682;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #d33682;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;
diff --git a/css/theme/white.css b/css/theme/white.css
index b10dd0e8..16a1d233 100644
--- a/css/theme/white.css
+++ b/css/theme/white.css
@@ -25,6 +25,11 @@ body {
   background: #98bdef;
   text-shadow: none; }
 
+::-moz-selection {
+  color: #fff;
+  background: #98bdef;
+  text-shadow: none; }
+
 .reveal .slides > section,
 .reveal .slides > section > section {
   line-height: 1.3;