:root {
    --bg-darkest: #060609;
    --bg-darker: #0c0d12;
    --bg-dark: #11141e;
    --bg-medium: #181b29;
    --bg-light: #252a3f;
    --accent-primary: #a78bfa;
    --accent-secondary: #c084fc;
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --accent-danger: #ef4444;
    --accent-purple: #c084fc;
    --accent-pink: #f472b6;
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;
    --text-muted: #6b7280;
    --border-default: #2d3142;
    --border-muted: #1d202e;
    --syntax-keyword: #f472b6;
    --syntax-string: #34d399;
    --syntax-number: #fb923c;
    --syntax-function: #60a5fa;
    --syntax-comment: #6b7280;
    --syntax-operator: #38bdf8;
    --syntax-tag: #fb7185;
    --syntax-attribute: #f59e0b;
    --syntax-property: #60a5fa;
    --syntax-selector: #34d399;
    --syntax-variable: #e879f9;
    --syntax-regex: #a78bfa;
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 24px;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-size-xs: 11px;
    --font-size-sm: 12px;
    --font-size-md: 13px;
    --font-size-lg: 14px;
    --transition-fast: 0.15s ease;
    --transition-normal: 0.25s ease;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; overflow: hidden; overscroll-behavior: none; }
body { font-family: var(--font-sans); font-size: var(--font-size-md); background: var(--bg-darkest); color: var(--text-primary); line-height: 1.5; }
.app { display: flex; flex-direction: column; height: 100vh; }

.header { display: flex; justify-content: space-between; align-items: center; padding: 12px 20px; background: var(--bg-darker); border-bottom: 1px solid var(--border-default); position: relative; z-index: 30; }
.header-left { display: flex; align-items: center; gap: 12px; }
.header h1 { font-size: 18px; font-weight: 800; letter-spacing: -0.5px; background: linear-gradient(90deg, var(--accent-pink), var(--accent-primary)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; margin: 0; }
.header-actions { display: flex; gap: 10px; align-items: center; }
.header button { padding: 6px 14px; background: var(--bg-medium); border: 1px solid var(--border-default); color: var(--text-primary); cursor: pointer; border-radius: 6px; font-weight: 500; font-size: 13px; transition: all var(--transition-fast); }
.header button:hover { background: var(--bg-light); border-color: var(--accent-primary); transform: translateY(-1px); }
.tree-toggle { background: none; border: 1px solid var(--border-default); color: var(--text-secondary); cursor: pointer; padding: 6px 8px; font-size: 18px; border-radius: 6px; transition: all var(--transition-fast); }
.tree-toggle:hover { color: var(--accent-primary); border-color: var(--accent-primary); background: var(--bg-medium); }

.tabs { display: flex; background: var(--bg-dark); border-bottom: 1px solid var(--border-default); position: relative; z-index: 20; }
.tab { padding: 10px 20px; background: none; border: none; color: var(--text-secondary); cursor: pointer; border-bottom: 2px solid transparent; font-weight: 600; font-size: 14px; transition: all var(--transition-fast); }
.tab.active { color: var(--accent-primary); border-bottom-color: var(--accent-primary); }
.tab:hover { background: var(--bg-medium); }

.editor-wrapper { display: flex; flex: 1; overflow: hidden; position: relative; }
.file-tree { width: 220px; min-width: 220px; background: var(--bg-darker); border-right: 1px solid var(--border-default); overflow-y: auto; padding: 8px 0; transition: width 0.25s ease, min-width 0.25s ease, padding 0.25s ease, transform 0.25s ease; position: relative; z-index: 10; }
.editor-wrapper.tree-collapsed .file-tree { width: 0; min-width: 0; padding: 0; border-right: none; overflow: hidden; }
.file-item { display: flex; align-items: center; gap: var(--spacing-sm); padding: 6px 12px; font-size: 13px; color: var(--text-secondary); cursor: pointer; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; transition: all var(--transition-fast); border-left: 2px solid transparent; }
.file-item:hover { background: var(--bg-medium); color: var(--text-primary); }
.file-item.active { background: var(--bg-medium); color: var(--accent-primary); border-left-color: var(--accent-primary); }
.file-item.new-file { color: var(--accent-pink); font-weight: 600; }

.editor-pane { flex: 1; display: flex; flex-direction: column; min-width: 0; position: relative; z-index: 5; }
.editor-bar { padding: 8px 12px; background: var(--bg-dark); border-bottom: 1px solid var(--border-default); font-size: 13px; color: var(--accent-primary); display: flex; align-items: center; gap: 10px; }
#editor-title { font-weight: 600; color: var(--accent-primary); }
.editor-content-wrapper { position: relative; flex: 1; background: var(--bg-darkest); font-family: var(--font-mono); font-size: var(--font-size-md); overflow: hidden; }

.line-numbers { position: absolute; top: 0; left: 0; width: 50px; height: 100%; padding: var(--spacing-lg) 8px; background: var(--bg-darkest); color: var(--text-muted); font-family: var(--font-mono); font-size: var(--font-size-md); line-height: 1.6; text-align: right; user-select: none; border-right: 1px solid var(--border-muted); overflow: hidden; scrollbar-width: none; z-index: 3; }
.line-numbers::-webkit-scrollbar { display: none; }
.line-numbers__line { height: 21px; }
.line-numbers__line--active { color: var(--text-primary); }

.textarea { position: absolute; top: 0; left: 0; width: 100%; height: 100%; padding: var(--spacing-lg); padding-left: 58px; background: transparent; border: none; outline: none; resize: none; font-family: var(--font-mono); font-size: var(--font-size-md); line-height: 1.6; color: transparent; caret-color: var(--text-primary); white-space: pre-wrap; overflow: auto; tab-size: 2; -moz-tab-size: 2; scrollbar-width: none; z-index: 2; }
.textarea::-webkit-scrollbar { display: none; }
.syntax-highlight { position: absolute; top: 0; left: 0; width: 100%; height: 100%; padding: var(--spacing-lg); padding-left: 58px; font-family: var(--font-mono); font-size: var(--font-size-md); line-height: 1.6; white-space: pre-wrap; word-break: break-all; pointer-events: none; overflow: hidden; z-index: 1; }

.preview { flex: 1; overflow: hidden; height: 100%; }
.preview iframe { width: 100%; height: 100%; border: none; background: #ffffff; }

.command-palette, .modal-overlay { position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: 1000; display: flex; align-items: flex-start; justify-content: center; padding-top: 80px; background: rgba(0, 0, 0, 0.6); backdrop-filter: blur(6px); transition: opacity 0.2s ease; }
.command-palette--hidden, .modal-overlay[style*="display: none"] { opacity: 0; pointer-events: none; }
.command-palette__dialog, .modal-box { width: 620px; max-width: 92%; background: var(--bg-dark); border: 1px solid var(--border-default); border-radius: 8px; overflow: hidden; box-shadow: 0 20px 40px rgba(0,0,0,0.4); animation: paletteSlideIn 0.2s ease; }
@keyframes paletteSlideIn { from { transform: translateY(-20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
.modal-header { padding: 14px 16px; font-size: 14px; font-weight: 600; color: var(--text-primary); border-bottom: 1px solid var(--border-default); background: var(--bg-medium); }

.command-palette__input-wrapper { border-bottom: 1px solid var(--border-default); }
.command-palette__input { width: 100%; padding: 14px 16px; background: var(--bg-dark); border: none; outline: none; color: var(--text-primary); font-size: 15px; font-family: var(--font-sans); }
.command-palette__input::placeholder { color: var(--text-muted); }
.command-palette__results { max-height: 400px; overflow-y: auto; }
.command-palette__item { padding: 10px 16px; cursor: pointer; color: var(--text-secondary); font-size: 14px; display: flex; align-items: center; gap: 12px; transition: background var(--transition-fast); }
.command-palette__item:hover, .command-palette__item--selected { background: var(--bg-medium); color: var(--text-primary); }
.command-palette__item-icon { width: 20px; text-align: center; font-size: 16px; opacity: 0.8; }
.command-palette__item-label { flex: 1; }
.command-palette__item-shortcut { margin-left: auto; padding: 2px 6px; font-size: 11px; background: var(--bg-light); border: 1px solid var(--border-default); border-radius: 4px; color: var(--text-muted); font-family: var(--font-mono); }

.modal-body textarea { width: 100%; min-height: 120px; padding: 12px 16px; background: var(--bg-darker); border: none; border-bottom: 1px solid var(--border-default); outline: none; color: var(--text-primary); font-family: var(--font-mono); font-size: 13px; resize: vertical; }
.modal-body textarea::placeholder { color: var(--text-muted); }
#gemini-output { background: var(--bg-darkest); color: var(--accent-purple); }
.modal-actions { padding: 12px 16px; display: flex; justify-content: flex-end; gap: 8px; background: var(--bg-medium); }
.modal-actions button { padding: 8px 16px; background: var(--accent-primary); color: white; border: none; border-radius: 6px; font-size: 13px; font-weight: 500; cursor: pointer; transition: background var(--transition-fast); }
.modal-actions button:hover:not(:disabled) { background: var(--accent-secondary); }
.modal-actions button:disabled { opacity: 0.5; cursor: not-allowed; }

.modal-list { max-height: 400px; overflow-y: auto; padding: 8px; }
.modal-list-item { padding: 10px 16px; cursor: pointer; color: var(--text-secondary); font-size: 14px; display: flex; align-items: center; gap: 8px; transition: background var(--transition-fast); border-radius: 4px; margin-bottom: 4px; }
.modal-list-item:hover { background: var(--bg-medium); color: var(--text-primary); }

#notifications-container { position: fixed; bottom: 20px; right: 20px; z-index: 2000; display: flex; flex-direction: column; gap: 10px; }
.notification { background: var(--bg-dark); border: 1px solid var(--border-default); border-left: 3px solid var(--accent-primary); border-radius: 6px; padding: 12px 16px; min-width: 300px; max-width: 420px; box-shadow: 0 4px 12px rgba(0,0,0,0.3); animation: slideIn 0.3s ease; }
.notification.success { border-left-color: var(--accent-success); }
.notification.error { border-left-color: var(--accent-danger); }
.notification.warning { border-left-color: var(--accent-warning); }
.notification-title { font-weight: 600; font-size: 14px; margin-bottom: 4px; }
.notification-message { font-size: 13px; color: var(--text-secondary); }
@keyframes slideIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }

.token-keyword { color: var(--syntax-keyword); }
.token-string { color: var(--syntax-string); }
.token-number { color: var(--syntax-number); }
.token-function { color: var(--syntax-function); }
.token-comment { color: var(--syntax-comment); font-style: italic; }
.token-operator { color: var(--syntax-operator); }
.token-punctuation { color: var(--text-secondary); }
.token-tag { color: var(--syntax-tag); }
.token-attribute { color: var(--syntax-attribute); }
.token-property { color: var(--syntax-property); }
.token-selector { color: var(--syntax-selector); }
.token-variable { color: var(--syntax-variable); }
.token-regex { color: var(--syntax-regex); }
.token-boolean { color: var(--syntax-keyword); }
.token-unit { color: var(--syntax-number); }

::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--bg-darker); }
::-webkit-scrollbar-thumb { background: var(--bg-light); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--border-default); }

@media (max-width: 768px) {
    .editor-wrapper:not(.tree-collapsed)::after { content: ''; position: absolute; inset: 0; background: rgba(0, 0, 0, 0.5); backdrop-filter: blur(2px); z-index: 10; opacity: 1; transition: opacity 0.25s ease; pointer-events: auto; }
    .editor-wrapper.tree-collapsed::after { opacity: 0; pointer-events: none; }
    .file-tree { position: absolute; top: 0; left: 0; height: 100%; width: 240px; z-index: 20; box-shadow: 4px 0 20px rgba(0,0,0,0.5); transform: translateX(0); transition: transform 0.25s ease; }
    .editor-wrapper.tree-collapsed .file-tree { transform: translateX(-100%); box-shadow: none; }
    .textarea, .syntax-highlight, .line-numbers { font-size: 16px; line-height: 1.7; }
    .line-numbers__line { height: 27px; }
    .header button, .tree-toggle { min-height: 44px; min-width: 44px; padding: 10px 14px; }
    .file-item { padding: 10px 12px; font-size: 15px; }
    .command-palette, .modal-overlay { padding-top: 40px; }
    .command-palette__dialog, .modal-box { max-height: 85vh; }
}

@media (max-width: 768px) {
    .header { padding: 10px 12px; }
    .header h1 { font-size: 16px; }
    .header-actions { gap: 6px; }
    .header button { padding: 6px 10px; font-size: 12px; }
}