diff --git a/developer-dark-theme.el b/developer-dark-theme.el
new file mode 100644
index 0000000..b336b15
--- /dev/null
+++ b/developer-dark-theme.el
@@ -0,0 +1,329 @@
+;;; developer-dark-theme.el --- A balanced dark theme for C, Python, and QML -*- lexical-binding: t -*-
+
+;; Copyright (C) 2024
+
+;; Author: Developer
+;; Version: 1.0
+;; Package-Requires: ((emacs "24.3"))
+;; Keywords: faces, themes
+
+;;; Commentary:
+
+;; A carefully crafted dark theme with balanced contrast.
+;; Optimized for C/C++, Python, and QML development.
+;; Not too faded, not too extreme - just right.
+
+;;; Code:
+
+(deftheme developer-dark
+  "A balanced dark theme for programming.")
+
+(let ((class '((class color) (min-colors 89)))
+      ;; Base colors
+      (bg-main     "#1a1d23")      ; Dark blue-grey background
+      (bg-dim      "#14171c")      ; Darker for modeline inactive
+      (bg-active   "#252930")      ; Lighter for selections
+      (bg-region   "#2d3640")      ; Selection background
+      (bg-hl-line  "#222630")      ; Current line highlight
+      
+      ;; Foreground colors
+      (fg-main     "#d4d8df")      ; Main text - good readability
+      (fg-dim      "#969ba7")      ; Comments, less important
+      (fg-bright   "#e8ecf2")      ; Emphasized text
+      
+      ;; Syntax colors - balanced, not too bright
+      (red         "#e06c75")      ; Errors, important warnings
+      (red-bright  "#ff7a85")      ; Bright red for critical
+      (green       "#98c379")      ; Strings, success
+      (green-bright "#b5e890")     ; Bright green
+      (yellow      "#e5c07b")      ; Warnings, special keywords
+      (yellow-bright "#ffd787")    ; Bright yellow
+      (blue        "#61afef")      ; Functions, primary keywords
+      (blue-bright "#74c7ff")      ; Bright blue
+      (magenta     "#c678dd")      ; Constants, special syntax
+      (magenta-bright "#e198ff")   ; Bright magenta
+      (cyan        "#56b6c2")      ; Types, classes
+      (cyan-bright "#7fd8e8")      ; Bright cyan
+      (orange      "#d19a66")      ; Numbers, preprocessor
+      (purple      "#a984d4")      ; Special identifiers
+      
+      ;; UI colors
+      (border      "#3a4049")      ; Borders, separators
+      (cursor      "#61afef")      ; Cursor color
+      (fringe      "#1e2228")      ; Fringe background
+      (modeline-bg "#232830")      ; Active modeline
+      (modeline-fg "#b8bcc5"))     ; Modeline text
+
+  (custom-theme-set-faces
+   'developer-dark
+   
+   ;; Basic faces
+   `(default ((,class (:background ,bg-main :foreground ,fg-main))))
+   `(cursor ((,class (:background ,cursor))))
+   `(region ((,class (:background ,bg-region :extend t))))
+   `(highlight ((,class (:background ,bg-active))))
+   `(hl-line ((,class (:background ,bg-hl-line :extend t))))
+   `(fringe ((,class (:background ,fringe :foreground ,fg-dim))))
+   `(vertical-border ((,class (:foreground ,border))))
+   `(window-divider ((,class (:foreground ,border))))
+   `(window-divider-first-pixel ((,class (:foreground ,border))))
+   `(window-divider-last-pixel ((,class (:foreground ,border))))
+   
+   ;; Font lock faces - syntax highlighting
+   `(font-lock-builtin-face ((,class (:foreground ,blue))))
+   `(font-lock-comment-face ((,class (:foreground ,fg-dim :slant italic))))
+   `(font-lock-comment-delimiter-face ((,class (:foreground ,fg-dim))))
+   `(font-lock-constant-face ((,class (:foreground ,magenta))))
+   `(font-lock-doc-face ((,class (:foreground ,green))))
+   `(font-lock-function-name-face ((,class (:foreground ,blue :weight medium))))
+   `(font-lock-keyword-face ((,class (:foreground ,purple :weight medium))))
+   `(font-lock-negation-char-face ((,class (:foreground ,red))))
+   `(font-lock-preprocessor-face ((,class (:foreground ,orange))))
+   `(font-lock-regexp-grouping-backslash ((,class (:foreground ,yellow))))
+   `(font-lock-regexp-grouping-construct ((,class (:foreground ,purple))))
+   `(font-lock-string-face ((,class (:foreground ,green))))
+   `(font-lock-type-face ((,class (:foreground ,cyan))))
+   `(font-lock-variable-name-face ((,class (:foreground ,fg-main))))
+   `(font-lock-warning-face ((,class (:foreground ,yellow :weight bold))))
+   
+   ;; C/C++ specific
+   `(c-annotation-face ((,class (:foreground ,magenta))))
+   
+   ;; Line numbers
+   `(line-number ((,class (:background ,bg-main :foreground ,fg-dim))))
+   `(line-number-current-line ((,class (:background ,bg-hl-line :foreground ,yellow :weight bold))))
+   
+   ;; Mode line
+   `(mode-line ((,class (:background ,modeline-bg :foreground ,modeline-fg :box (:line-width 1 :color ,border)))))
+   `(mode-line-inactive ((,class (:background ,bg-dim :foreground ,fg-dim :box (:line-width 1 :color ,border)))))
+   `(mode-line-buffer-id ((,class (:weight bold :foreground ,blue))))
+   `(mode-line-emphasis ((,class (:foreground ,fg-bright :weight bold))))
+   `(mode-line-highlight ((,class (:background ,bg-active))))
+   
+   ;; Search and replace
+   `(isearch ((,class (:background ,yellow :foreground ,bg-main :weight bold))))
+   `(isearch-fail ((,class (:background ,red :foreground ,fg-bright))))
+   `(lazy-highlight ((,class (:background ,bg-active :foreground ,yellow))))
+   `(match ((,class (:background ,green :foreground ,bg-main))))
+   
+   ;; Diff-hl (git changes in fringe)
+   `(diff-hl-change ((,class (:foreground ,blue :background ,blue))))
+   `(diff-hl-delete ((,class (:foreground ,red :background ,red))))
+   `(diff-hl-insert ((,class (:foreground ,green :background ,green))))
+   
+   ;; Diff mode
+   `(diff-added ((,class (:background "#1e3a28" :foreground ,green :extend t))))
+   `(diff-removed ((,class (:background "#3a1e28" :foreground ,red :extend t))))
+   `(diff-changed ((,class (:background "#2a2a3a" :extend t))))
+   `(diff-header ((,class (:background ,bg-dim :foreground ,fg-bright :weight bold))))
+   `(diff-file-header ((,class (:background ,bg-dim :foreground ,blue :weight bold))))
+   `(diff-hunk-header ((,class (:background ,bg-active :foreground ,purple))))
+   
+   ;; Company (auto-completion)
+   `(company-tooltip ((,class (:background ,bg-active :foreground ,fg-main))))
+   `(company-tooltip-selection ((,class (:background ,blue :foreground ,bg-main))))
+   `(company-tooltip-common ((,class (:foreground ,yellow :weight bold))))
+   `(company-tooltip-common-selection ((,class (:foreground ,bg-main :weight bold))))
+   `(company-tooltip-annotation ((,class (:foreground ,cyan))))
+   `(company-tooltip-annotation-selection ((,class (:foreground ,bg-main))))
+   `(company-scrollbar-bg ((,class (:background ,bg-dim))))
+   `(company-scrollbar-fg ((,class (:background ,border))))
+   `(company-preview ((,class (:background ,bg-active :foreground ,green))))
+   `(company-preview-common ((,class (:background ,bg-active :foreground ,yellow))))
+   
+   ;; Helm
+   `(helm-header ((,class (:background ,bg-dim :foreground ,fg-main :weight bold :extend t))))
+   `(helm-source-header ((,class (:background ,bg-active :foreground ,fg-bright :weight bold :extend t))))
+   `(helm-selection ((,class (:background ,bg-region :weight bold :extend t))))
+   `(helm-visible-mark ((,class (:background ,blue :foreground ,bg-main))))
+   `(helm-candidate-number ((,class (:foreground ,green :weight bold))))
+   `(helm-separator ((,class (:foreground ,red))))
+   `(helm-match ((,class (:foreground ,yellow :weight bold))))
+   `(helm-M-x-key ((,class (:foreground ,orange :weight bold))))
+   `(helm-buffer-not-saved ((,class (:foreground ,red))))
+   `(helm-buffer-process ((,class (:foreground ,magenta))))
+   `(helm-buffer-saved-out ((,class (:foreground ,yellow))))
+   `(helm-buffer-size ((,class (:foreground ,fg-dim))))
+   `(helm-buffer-directory ((,class (:foreground ,blue :weight bold))))
+   `(helm-buffer-file ((,class (:foreground ,fg-main))))
+   `(helm-ff-directory ((,class (:foreground ,blue :weight bold))))
+   `(helm-ff-file ((,class (:foreground ,fg-main))))
+   `(helm-ff-executable ((,class (:foreground ,green))))
+   `(helm-ff-symlink ((,class (:foreground ,cyan))))
+   `(helm-ff-prefix ((,class (:background ,yellow :foreground ,bg-main))))
+   
+   ;; Treemacs
+   `(treemacs-directory-face ((,class (:foreground ,blue))))
+   `(treemacs-file-face ((,class (:foreground ,fg-main))))
+   `(treemacs-root-face ((,class (:foreground ,green :weight bold))))
+   `(treemacs-git-modified-face ((,class (:foreground ,orange))))
+   `(treemacs-git-added-face ((,class (:foreground ,green))))
+   `(treemacs-git-untracked-face ((,class (:foreground ,fg-dim))))
+   `(treemacs-git-renamed-face ((,class (:foreground ,yellow))))
+   `(treemacs-git-deleted-face ((,class (:foreground ,red))))
+   
+   ;; Magit
+   `(magit-branch-current ((,class (:foreground ,green :weight bold))))
+   `(magit-branch-local ((,class (:foreground ,blue))))
+   `(magit-branch-remote ((,class (:foreground ,magenta))))
+   `(magit-diff-added ((,class (:background "#1e3a28" :foreground ,green :extend t))))
+   `(magit-diff-added-highlight ((,class (:background "#2a4a34" :foreground ,green :extend t))))
+   `(magit-diff-removed ((,class (:background "#3a1e28" :foreground ,red :extend t))))
+   `(magit-diff-removed-highlight ((,class (:background "#4a2a34" :foreground ,red :extend t))))
+   `(magit-diff-context ((,class (:foreground ,fg-dim :extend t))))
+   `(magit-diff-context-highlight ((,class (:background ,bg-hl-line :foreground ,fg-main :extend t))))
+   `(magit-section-heading ((,class (:foreground ,blue :weight bold))))
+   `(magit-section-highlight ((,class (:background ,bg-hl-line :extend t))))
+   `(magit-hash ((,class (:foreground ,fg-dim))))
+   
+   ;; LSP
+   `(lsp-face-highlight-textual ((,class (:background ,bg-active))))
+   `(lsp-face-highlight-read ((,class (:background ,bg-active))))
+   `(lsp-face-highlight-write ((,class (:background ,bg-region))))
+   `(lsp-ui-doc-background ((,class (:background ,bg-active))))
+   `(lsp-ui-doc-border ((,class (:foreground ,border))))
+   `(lsp-ui-doc-header ((,class (:background ,blue :foreground ,bg-main :weight bold))))
+   `(lsp-ui-peek-peek ((,class (:background ,bg-active))))
+   `(lsp-ui-peek-list ((,class (:background ,bg-dim))))
+   `(lsp-ui-peek-filename ((,class (:foreground ,orange :weight bold))))
+   `(lsp-ui-peek-selection ((,class (:background ,bg-region))))
+   `(lsp-ui-peek-highlight ((,class (:background ,yellow :foreground ,bg-main))))
+   `(lsp-ui-sideline-code-action ((,class (:foreground ,yellow))))
+   
+   ;; Flycheck
+   `(flycheck-error ((,class (:underline (:style wave :color ,red)))))
+   `(flycheck-warning ((,class (:underline (:style wave :color ,yellow)))))
+   `(flycheck-info ((,class (:underline (:style wave :color ,cyan)))))
+   `(flycheck-fringe-error ((,class (:foreground ,red))))
+   `(flycheck-fringe-warning ((,class (:foreground ,yellow))))
+   `(flycheck-fringe-info ((,class (:foreground ,cyan))))
+   
+   ;; Rainbow delimiters
+   `(rainbow-delimiters-depth-1-face ((,class (:foreground ,blue))))
+   `(rainbow-delimiters-depth-2-face ((,class (:foreground ,green))))
+   `(rainbow-delimiters-depth-3-face ((,class (:foreground ,yellow))))
+   `(rainbow-delimiters-depth-4-face ((,class (:foreground ,cyan))))
+   `(rainbow-delimiters-depth-5-face ((,class (:foreground ,magenta))))
+   `(rainbow-delimiters-depth-6-face ((,class (:foreground ,orange))))
+   `(rainbow-delimiters-depth-7-face ((,class (:foreground ,blue-bright))))
+   `(rainbow-delimiters-depth-8-face ((,class (:foreground ,green-bright))))
+   `(rainbow-delimiters-depth-9-face ((,class (:foreground ,red-bright))))
+   
+   ;; Org mode
+   `(org-level-1 ((,class (:foreground ,blue :weight bold))))
+   `(org-level-2 ((,class (:foreground ,green :weight bold))))
+   `(org-level-3 ((,class (:foreground ,yellow :weight bold))))
+   `(org-level-4 ((,class (:foreground ,cyan :weight bold))))
+   `(org-level-5 ((,class (:foreground ,magenta :weight bold))))
+   `(org-level-6 ((,class (:foreground ,orange :weight bold))))
+   `(org-level-7 ((,class (:foreground ,purple :weight bold))))
+   `(org-level-8 ((,class (:foreground ,fg-main :weight bold))))
+   `(org-link ((,class (:foreground ,blue :underline t))))
+   `(org-code ((,class (:background ,bg-active :foreground ,orange))))
+   `(org-block ((,class (:background ,bg-dim :extend t))))
+   `(org-block-begin-line ((,class (:background ,bg-dim :foreground ,fg-dim :extend t))))
+   `(org-block-end-line ((,class (:background ,bg-dim :foreground ,fg-dim :extend t))))
+   
+   ;; Markdown
+   `(markdown-header-face-1 ((,class (:foreground ,blue :weight bold))))
+   `(markdown-header-face-2 ((,class (:foreground ,green :weight bold))))
+   `(markdown-header-face-3 ((,class (:foreground ,yellow :weight bold))))
+   `(markdown-header-face-4 ((,class (:foreground ,cyan :weight bold))))
+   `(markdown-header-face-5 ((,class (:foreground ,magenta :weight bold))))
+   `(markdown-header-face-6 ((,class (:foreground ,orange :weight bold))))
+   `(markdown-code-face ((,class (:background ,bg-active :foreground ,orange))))
+   `(markdown-inline-code-face ((,class (:background ,bg-active :foreground ,orange))))
+   `(markdown-link-face ((,class (:foreground ,blue :underline t))))
+   `(markdown-url-face ((,class (:foreground ,cyan :underline t))))
+   
+   ;; Which-key
+   `(which-key-key-face ((,class (:foreground ,green :weight bold))))
+   `(which-key-separator-face ((,class (:foreground ,fg-dim))))
+   `(which-key-note-face ((,class (:foreground ,fg-dim :slant italic))))
+   `(which-key-command-description-face ((,class (:foreground ,fg-main))))
+   `(which-key-group-description-face ((,class (:foreground ,purple))))
+   
+   ;; Minibuffer
+   `(minibuffer-prompt ((,class (:foreground ,blue :weight bold))))
+   `(completions-common-part ((,class (:foreground ,yellow :weight bold))))
+   `(completions-first-difference ((,class (:foreground ,orange :weight bold))))
+   
+   ;; Messages
+   `(success ((,class (:foreground ,green :weight bold))))
+   `(warning ((,class (:foreground ,yellow :weight bold))))
+   `(error ((,class (:foreground ,red :weight bold))))
+   
+   ;; Links
+   `(link ((,class (:foreground ,blue :underline t))))
+   `(link-visited ((,class (:foreground ,purple :underline t))))
+   
+   ;; Buttons
+   `(button ((,class (:foreground ,cyan :underline t))))
+   `(custom-button ((,class (:background ,bg-active :foreground ,fg-main :box (:line-width 1 :color ,border)))))
+   `(custom-button-mouse ((,class (:background ,bg-region :foreground ,fg-bright))))
+   `(custom-button-pressed ((,class (:background ,bg-region :foreground ,fg-bright))))
+   
+   ;; Widgets
+   `(widget-field ((,class (:background ,bg-active :foreground ,fg-main))))
+   `(widget-single-line-field ((,class (:background ,bg-active :foreground ,fg-main))))
+   
+   ;; Origami (code folding)
+   `(origami-fold-header-face ((,class (:foreground ,fg-dim :box nil))))
+   `(origami-fold-fringe-face ((,class (:foreground ,fg-dim))))
+   `(origami-fold-replacement-face ((,class (:foreground ,fg-dim))))
+   
+   ;; QML mode specific
+   `(qml-operator-face ((,class (:foreground ,orange))))
+   
+   ;; Python mode specific
+   `(python-info-docstring-face ((,class (:foreground ,green :slant italic))))
+   
+   ;; Show paren
+   `(show-paren-match ((,class (:background ,bg-region :foreground ,yellow :weight bold))))
+   `(show-paren-mismatch ((,class (:background ,red :foreground ,fg-bright :weight bold))))
+   
+   ;; Highlight indentation
+   `(highlight-indentation-face ((,class (:background ,bg-dim))))
+   `(highlight-indentation-current-column-face ((,class (:background ,bg-active))))
+   
+   ;; Whitespace
+   `(whitespace-space ((,class (:foreground ,bg-active))))
+   `(whitespace-tab ((,class (:foreground ,bg-active))))
+   `(whitespace-trailing ((,class (:background ,red :foreground ,yellow))))
+   `(whitespace-line ((,class (:background ,bg-active :foreground ,red))))
+   
+   ;; Terminal
+   `(term-color-black ((,class (:foreground ,bg-main :background ,bg-main))))
+   `(term-color-red ((,class (:foreground ,red :background ,red))))
+   `(term-color-green ((,class (:foreground ,green :background ,green))))
+   `(term-color-yellow ((,class (:foreground ,yellow :background ,yellow))))
+   `(term-color-blue ((,class (:foreground ,blue :background ,blue))))
+   `(term-color-magenta ((,class (:foreground ,magenta :background ,magenta))))
+   `(term-color-cyan ((,class (:foreground ,cyan :background ,cyan))))
+   `(term-color-white ((,class (:foreground ,fg-main :background ,fg-main))))
+   
+   ;; Ansi colors
+   `(ansi-color-black ((,class (:foreground ,bg-main :background ,bg-main))))
+   `(ansi-color-red ((,class (:foreground ,red :background ,red))))
+   `(ansi-color-green ((,class (:foreground ,green :background ,green))))
+   `(ansi-color-yellow ((,class (:foreground ,yellow :background ,yellow))))
+   `(ansi-color-blue ((,class (:foreground ,blue :background ,blue))))
+   `(ansi-color-magenta ((,class (:foreground ,magenta :background ,magenta))))
+   `(ansi-color-cyan ((,class (:foreground ,cyan :background ,cyan))))
+   `(ansi-color-white ((,class (:foreground ,fg-main :background ,fg-main))))))
+
+;;;###autoload
+(when load-file-name
+  (add-to-list 'custom-theme-load-path
+               (file-name-as-directory (file-name-directory load-file-name))))
+
+;;;###autoload
+(defun developer-dark-theme-reload ()
+  "Reload the developer-dark theme."
+  (interactive)
+  (disable-theme 'developer-dark)
+  (load-theme 'developer-dark t))
+
+(provide-theme 'developer-dark)
+
+;;; developer-dark-theme.el ends here
\ No newline at end of file
diff --git a/init.el b/init.el
index 4312076..58a5ea1 100644
--- a/init.el
+++ b/init.el
@@ -66,9 +66,10 @@
  '(before-save-hook '(delete-trailing-whitespace))
  '(column-number-mode t)
  '(cua-mode t)
- '(custom-enabled-themes '(modus-vivendi))
+ '(custom-enabled-themes '(developer-dark))
  '(custom-safe-themes
-   '("9fb69436c074b82a62b78b8d733e6274d0bd16d156f7b094e2afe4345c040c49"
+   '("de2f009a49f8eaf2f323519d86016849cd1716d979bc3f7e4afb58899e52ddb7"
+     "9fb69436c074b82a62b78b8d733e6274d0bd16d156f7b094e2afe4345c040c49"
      "004f174754c688f358fa2afc4f8699b5db647fbfaa0d6b55ff39f63e05bfbbf5"
      "ca1b398ceb1b61709197478dc7f705b8337a0a9631e399948e643520c5557382"
      "75eef60308d7328ed14fa27002e85de255c2342e73275173a14ed3aa1643d545"
@@ -122,9 +123,9 @@
  ;; Your init file should contain only one such instance.
  ;; If there is more than one, they won't work right.
  '(default ((t (:family "0xProto Nerd Font" :foundry "0x  " :slant normal :weight regular :height 120 :width normal))))
- '(diff-hl-insert ((t (:background "green3" :foreground "green3"))))
+ '(diff-hl-change ((t (:background "blue3" :foreground "blue3"))))
  '(diff-hl-delete ((t (:background "red3" :foreground "red3"))))
- '(diff-hl-change ((t (:background "blue3" :foreground "blue3")))))
+ '(diff-hl-insert ((t (:background "green3" :foreground "green3")))))
 
 ;;; Helm Configuration (Primary interface)
 (use-package helm
@@ -739,6 +740,22 @@
       (error
        (message "mu4e configuration available but mu4e not installed. Install mu4e package to enable email.")))))
 
+;;; Theme Management
+(defun load-developer-dark-theme ()
+  "Load the custom developer-dark theme."
+  (interactive)
+  (load-theme 'developer-dark t)
+  (message "Developer Dark theme loaded"))
+
+(defun switch-theme (theme)
+  "Switch to a different theme interactively."
+  (interactive
+   (list (intern (completing-read "Load theme: "
+                                  (mapcar #'symbol-name (custom-available-themes))))))
+  (mapc #'disable-theme custom-enabled-themes)
+  (load-theme theme t)
+  (message "Switched to %s theme" theme))
+
 ;;; Development Mode Information
 (defun show-dev-mode-info ()
   "Show information about development mode."