Fix print preview paper dimensions and cleanup redundant CSS files

- Change print preview to landscape orientation (11" x 8.5")
- Fix paper div to render at exact 1056x816 pixels
- Add 48px padding (0.5 inches) directly to paper div
- Remove CSS file redundancy: deleted styles.css.backup, styles/base.css, styles/default.css
- Improve modal sizing to accommodate paper dimensions

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/styles/base.css

@@ -1,51 +0,0 @@
-/* Base Styles - Always Loaded */
-* {
-    margin: 0;
-    padding: 0;
-    box-sizing: border-box;
-}
-
-body {
-    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
-    background-color: #f8f9fa;
-    color: #333;
-    line-height: 1.6;
-}
-
-.app {
-    min-height: 100vh;
-    display: flex;
-    flex-direction: row;
-}
-
-.login-layout {
-    min-height: 100vh;
-    display: flex;
-    flex-direction: column;
-    width: 100%;
-}
-
-/* Base Layout */
-.main-content {
-    flex: 1;
-    margin-left: 280px;
-    overflow-x: hidden;
-}
-
-/* Basic Form Elements */
-input, select, textarea, button {
-    font-family: inherit;
-}
-
-/* Utility Classes */
-.loading {
-    opacity: 0.7;
-}
-
-.error {
-    color: #dc3545;
-}
-
-.success {
-    color: #28a745;
-}