Initial release v1.2.0 — Hellion NewTab Browser Extension

Persoenlicher Bookmark-Dashboard als Browser-Extension.
8 Themes, Drag & Drop, Sticky Notes, JSON Export/Import.
Chrome, Edge, Brave, Opera, Vivaldi (MV3) + Firefox (MV2).

Includes GitHub Actions for security scanning, code quality
validation, and automated release packaging.

src/js/themes.js

@@ -0,0 +1,30 @@
+/* =============================================
+   HELLION NEWTAB — themes.js
+   Theme-Definitionen & Anwendungslogik
+   ============================================= */
+
+const THEMES = {
+  'astronaut':      { bg: 'assets/themes/bg-astronaut.jpg' },
+  'cosmic-clock':   { bg: 'assets/themes/bg-cosmic-clock.jpg' },
+  'void-mage':      { bg: 'assets/themes/bg-void-mage.jpg' },
+  'merchantman':    { bg: 'assets/themes/bg-merchantman.webp' },
+  'julia-jin':      { bg: 'assets/themes/bg-julia-jin.png' },
+  'sc-sunset':      { bg: 'assets/themes/bg-sc-sunset.jpg' },
+  'hellion-hud':    { bg: 'assets/themes/bg-hellion-hud.png' },
+  'hellion-energy': { bg: 'assets/themes/bg-hellion-energy.jpg' }
+};
+
+function applyTheme(themeName, skipBgOverride) {
+  const theme = THEMES[themeName];
+  if (!theme) return;
+
+  document.documentElement.setAttribute('data-theme', themeName);
+
+  if (!skipBgOverride) {
+    document.getElementById('bgLayer').style.backgroundImage = `url('${theme.bg}')`;
+  }
+
+  document.querySelectorAll('.theme-card').forEach(card => {
+    card.classList.toggle('active', card.dataset.value === themeName);
+  });
+}