diff --git a/src/language/specs.rs b/src/language/specs.rs
index 09b6520..714430b 100644
--- a/src/language/specs.rs
+++ b/src/language/specs.rs
@@ -3,6 +3,7 @@ use serde::{Deserialize, Serialize};
 
 /// A kind of node that can appear in a document.
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct ConstructSpec {
     pub name: String,
     pub arity: AritySpec,
@@ -15,10 +16,12 @@ pub struct ConstructSpec {
 
 /// A set of constructs. Can both include and be included by other sorts.
 #[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq, Hash)]
+#[serde(deny_unknown_fields)]
 pub struct SortSpec(pub Vec<String>);
 
 /// The sorts of children that a node is allowed to contain.
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub enum AritySpec {
     /// Designates a pure text node.
     Texty,
@@ -33,6 +36,7 @@ pub enum AritySpec {
 /// Describes the structure of a language, e.g. which constructs can appear
 /// in which positions.
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct GrammarSpec {
     pub constructs: Vec<ConstructSpec>,
     pub sorts: Vec<(String, SortSpec)>,
@@ -41,6 +45,7 @@ pub struct GrammarSpec {
 
 /// Describes how to display every construct in a language.
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct NotationSetSpec {
     /// A unqiue name for this set of notations
     pub name: String,
@@ -51,6 +56,7 @@ pub struct NotationSetSpec {
 /// A single notation, with a grammar describing its structure and a notation describing how to
 /// display it.
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct LanguageSpec {
     pub name: String,
     pub grammar: GrammarSpec,
diff --git a/src/style.rs b/src/style.rs
index 584dc2b..050a1ab 100644
--- a/src/style.rs
+++ b/src/style.rs
@@ -44,6 +44,7 @@ pub struct Style {
 }
 
 #[derive(Debug, Clone, Copy, Default, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub enum Priority {
     #[default]
     Low,
@@ -57,6 +58,7 @@ pub enum CursorHalf {
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub enum StyleLabel {
     Open,
     Close,
@@ -77,6 +79,7 @@ pub enum StyleLabel {
 
 // TODO: doc
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub enum Condition {
     IsEmptyText,
     IsCommentOrWs,
@@ -95,6 +98,7 @@ pub struct Rgb {
 }
 
 #[derive(Debug, Clone, Copy, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub enum Base16Color {
     /// Default Background
     Base00,
@@ -232,9 +236,9 @@ impl ColorTheme {
     /// The "default dark" Base16 colorscheme, by Chris Kempson (http://chriskempson.com)
     pub fn default_dark() -> ColorTheme {
         ColorTheme {
-            base00: Rgb::from_hex("#181818").bug(),
-            base01: Rgb::from_hex("#282828").bug(),
-            base02: Rgb::from_hex("#383838").bug(),
+            base00: Rgb::from_hex("#312121").bug(),
+            base01: Rgb::from_hex("#111111").bug(),
+            base02: Rgb::from_hex("#103030").bug(),
             base03: Rgb::from_hex("#585858").bug(),
             base04: Rgb::from_hex("#b8b8b8").bug(),
             base05: Rgb::from_hex("#d8d8d8").bug(),