diff --git a/backend/app/core/config.py b/backend/app/core/config.py
index 02f86d4..fde2bd5 100644
--- a/backend/app/core/config.py
+++ b/backend/app/core/config.py
@@ -5,16 +5,17 @@ This module handles environment variable loading and provides
 default values for configuration settings.
 """
 
+import ast
+import json
 import os
 from pathlib import Path
-from typing import Optional, List
-import json
-import ast
+from typing import List, Optional
 
 try:
     from dotenv import load_dotenv
+
     # Try to load .env file from project root
-    env_path = Path(__file__).parent.parent.parent.parent / '.env'
+    env_path = Path(__file__).parent.parent.parent.parent / ".env"
     if env_path.exists():
         load_dotenv(env_path)
 except ImportError:
@@ -25,7 +26,7 @@ except ImportError:
 class Settings:
     """Application settings loaded from environment variables."""
 
-    def __init__(self):
+    def __init__(self) -> None:
         """Initialize settings from environment variables."""
         # Application info
         self.app_name: str = os.getenv("APP_NAME", "UnitForge")
@@ -53,10 +54,15 @@ class Settings:
         self.log_level: str = os.getenv("LOG_LEVEL", "info")
 
         # Server configuration
-        self.host: str = os.getenv("HOST", "0.0.0.0")
+        self.host: str = os.getenv("HOST", "0.0.0.0")  # nosec B104
         self.port: int = int(os.getenv("PORT", "8000"))
         self.debug: bool = os.getenv("DEBUG", "").lower() in ("true", "1", "yes", "on")
-        self.reload: bool = os.getenv("RELOAD", "").lower() in ("true", "1", "yes", "on")
+        self.reload: bool = os.getenv("RELOAD", "").lower() in (
+            "true",
+            "1",
+            "yes",
+            "on",
+        )
         self.workers: int = int(os.getenv("WORKERS", "4"))
 
         # API configuration
@@ -77,7 +83,7 @@ class Settings:
         self.max_upload_size: int = int(os.getenv("MAX_UPLOAD_SIZE", "1048576"))
         self.allowed_extensions: List[str] = self._parse_list(
             "ALLOWED_EXTENSIONS",
-            [".service", ".timer", ".socket", ".mount", ".target", ".path"]
+            [".service", ".timer", ".socket", ".mount", ".target", ".path"],
         )
 
         # Template settings
@@ -92,9 +98,15 @@ class Settings:
 
         # Feature flags
         self.enable_api_metrics: bool = self._get_bool("ENABLE_API_METRICS", False)
-        self.enable_request_logging: bool = self._get_bool("ENABLE_REQUEST_LOGGING", True)
-        self.enable_template_caching: bool = self._get_bool("ENABLE_TEMPLATE_CACHING", True)
-        self.enable_validation_caching: bool = self._get_bool("ENABLE_VALIDATION_CACHING", True)
+        self.enable_request_logging: bool = self._get_bool(
+            "ENABLE_REQUEST_LOGGING", True
+        )
+        self.enable_template_caching: bool = self._get_bool(
+            "ENABLE_TEMPLATE_CACHING", True
+        )
+        self.enable_validation_caching: bool = self._get_bool(
+            "ENABLE_VALIDATION_CACHING", True
+        )
 
         # Performance settings
         self.request_timeout: int = int(os.getenv("REQUEST_TIMEOUT", "30"))
@@ -121,8 +133,12 @@ class Settings:
         # Template generation defaults
         self.default_user: str = os.getenv("DEFAULT_USER", "www-data")
         self.default_group: str = os.getenv("DEFAULT_GROUP", "www-data")
-        self.default_restart_policy: str = os.getenv("DEFAULT_RESTART_POLICY", "on-failure")
-        self.default_wanted_by: str = os.getenv("DEFAULT_WANTED_BY", "multi-user.target")
+        self.default_restart_policy: str = os.getenv(
+            "DEFAULT_RESTART_POLICY", "on-failure"
+        )
+        self.default_wanted_by: str = os.getenv(
+            "DEFAULT_WANTED_BY", "multi-user.target"
+        )
 
         # Security headers
         self.security_headers: bool = self._get_bool("SECURITY_HEADERS", True)
@@ -192,6 +208,7 @@ class Settings:
             if parsed:
                 return parsed
         except Exception:
+            # Fall back to comma-separated parsing if JSON/literal parsing fails
             pass
 
         # Fall back to comma-separated values
diff --git a/frontend/static/css/style.css b/frontend/static/css/style.css
index a89878c..f884f01 100644
--- a/frontend/static/css/style.css
+++ b/frontend/static/css/style.css
@@ -508,15 +508,15 @@ footer.bg-dark .text-muted {
     }
 
     .form-control {
-        background-color: #2d3748;
+        background-color: var(--bg-secondary);
         border-color: #4a5568;
-        color: #f7fafc;
+        color: #333;
     }
 
     .form-control:focus {
-        background-color: #2d3748;
+        background-color: var(--bg-secondary);
         border-color: var(--primary-color);
-        color: #f7fafc;
+        color: #333;
     }
 }