:root {
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --success: #10b981;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-800: #1f2937;
    --gray-900: #111827;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    width: 100%;
    height: 100vh;
    overflow: hidden;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.hidden { display: none !important; }

/* Share Button */
.share-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--primary);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
    z-index: 100;
    transition: all 0.3s ease;
}

.share-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* Connection Status */
.connection-status {
    position: fixed;
    top: 20px;
    left: 20px;
    background: rgba(255, 255, 255, 0.95);
    color: var(--gray-800);
    padding: 8px 16px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
    z-index: 100;
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #ef4444;
    animation: pulse 2s infinite;
}

.connection-status.connected .status-dot {
    background: var(--success);
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* App Container */
.app-container {
    display: flex;
    flex-direction: column;
    width: 100vw;
    height: 100vh;
    background: white;
}

/* Header */
.app-header {
    background: white;
    border-bottom: 1px solid var(--gray-200);
    padding: 12px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.header-left {
    display: flex;
    align-items: center;
    gap: 16px;
    flex: 1;
}

.header-left h1 {
    font-size: 18px;
    color: var(--gray-800);
}

.doc-title {
    flex: 1;
    max-width: 300px;
    padding: 8px 12px;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    font-size: 16px;
    color: var(--gray-800);
}

.doc-title:focus {
    outline: none;
    border-color: var(--primary);
}

.room-badge {
    background: var(--gray-100);
    color: var(--gray-800);
    padding: 6px 12px;
    border-radius: 16px;
    font-size: 12px;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.view-mode-toggle {
    display: flex;
    background: var(--gray-100);
    border-radius: 8px;
    padding: 4px;
    gap: 4px;
}

.mode-btn {
    padding: 8px 16px;
    background: transparent;
    border: none;
    border-radius: 6px;
    color: var(--gray-800);
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.mode-btn:hover {
    background: var(--gray-200);
}

.mode-btn.active {
    background: white;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.theme-toggle button {
    background: var(--gray-100);
    border: none;
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 18px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.theme-toggle button:hover {
    background: var(--gray-200);
}

/* Toolbar */
.editor-toolbar {
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
    padding: 8px 16px;
    display: flex;
    gap: 16px;
    align-items: center;
}

.toolbar-group {
    display: flex;
    gap: 4px;
}

.toolbar-btn {
    padding: 8px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    color: var(--gray-800);
    transition: all 0.2s ease;
}

.toolbar-btn:hover {
    background: var(--gray-100);
    border-color: var(--primary);
}

.toolbar-separator {
    width: 1px;
    height: 24px;
    background: var(--gray-200);
}

/* Editor Layout */
.editor-layout {
    flex: 1;
    display: flex;
    overflow: hidden;
}

.editor-pane, .preview-pane {
    flex: 1;
    overflow: hidden;
    position: relative;
}

.editor-layout.split .editor-pane,
.editor-layout.split .preview-pane {
    flex: 1;
    border-right: 1px solid var(--gray-200);
}

.editor-layout.split .preview-pane {
    border-right: none;
}

/* CodeMirror Overrides */
.CodeMirror {
    height: 100% !important;
    font-family: 'Courier New', Consolas, monospace;
    font-size: 16px;
    line-height: 1.6;
}

.CodeMirror-lines {
    padding: 20px 0;
}

.CodeMirror-line {
    padding: 0 20px;
}

/* Remote Cursors in Editor */
.remote-cursor {
    position: absolute;
    width: 2px;
    height: 20px;
    z-index: 100;
    animation: blink 1s infinite;
}

@keyframes blink {
    0%, 49% { opacity: 1; }
    50%, 100% { opacity: 0; }
}

.remote-cursor-label {
    position: absolute;
    top: -20px;
    left: 2px;
    background: inherit;
    color: white;
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 11px;
    white-space: nowrap;
    font-family: 'Segoe UI', sans-serif;
}

/* Preview Pane */
.preview-content {
    height: 100%;
    overflow-y: auto;
    padding: 40px;
    background: white;
    color: var(--gray-900);
}

.preview-content.dark {
    background: var(--gray-900);
    color: var(--gray-50);
}

/* Markdown Styling */
.preview-content h1 {
    font-size: 32px;
    margin: 24px 0 16px 0;
    border-bottom: 2px solid var(--gray-200);
    padding-bottom: 8px;
}

.preview-content h2 {
    font-size: 28px;
    margin: 20px 0 12px 0;
}

.preview-content h3 {
    font-size: 24px;
    margin: 16px 0 10px 0;
}

.preview-content p {
    margin: 12px 0;
    line-height: 1.7;
}

.preview-content code {
    background: var(--gray-100);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 14px;
}

.preview-content pre {
    background: var(--gray-900);
    color: var(--gray-50);
    padding: 16px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 12px 0;
}

.preview-content pre code {
    background: none;
    color: inherit;
}

.preview-content blockquote {
    border-left: 4px solid var(--primary);
    padding-left: 16px;
    margin: 12px 0;
    color: var(--gray-800);
    font-style: italic;
}

.preview-content ul, .preview-content ol {
    margin: 12px 0;
    padding-left: 24px;
}

.preview-content li {
    margin: 6px 0;
}

.preview-content a {
    color: var(--primary);
    text-decoration: none;
}

.preview-content a:hover {
    text-decoration: underline;
}

/* Status Bar */
.status-bar {
    background: var(--gray-50);
    border-top: 1px solid var(--gray-200);
    padding: 8px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    color: var(--gray-800);
}

.status-left {
    display: flex;
    gap: 16px;
}

.users-list {
    display: flex;
    gap: 8px;
}

.user-badge {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 12px;
    font-size: 12px;
}

.user-color-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

/* Dark Theme */
body.dark-theme .app-container {
    background: var(--gray-900);
}

body.dark-theme .app-header,
body.dark-theme .editor-toolbar,
body.dark-theme .status-bar {
    background: var(--gray-800);
    border-color: rgba(255, 255, 255, 0.1);
    color: var(--gray-50);
}

body.dark-theme .doc-title {
    background: var(--gray-900);
    border-color: rgba(255, 255, 255, 0.1);
    color: var(--gray-50);
}

body.dark-theme .toolbar-btn,
body.dark-theme .mode-btn {
    background: var(--gray-900);
    border-color: rgba(255, 255, 255, 0.1);
    color: var(--gray-50);
}

body.dark-theme .mode-btn.active {
    background: var(--primary);
    color: white;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .header-left h1 {
        font-size: 16px;
    }

    .doc-title {
        max-width: 150px;
        font-size: 14px;
    }

    .editor-toolbar {
        overflow-x: auto;
        padding: 8px;
    }

    .toolbar-btn {
        padding: 6px 10px;
        font-size: 12px;
    }

    .view-mode-toggle {
        flex-direction: column;
    }
}