:root {
    --surface: #ffffff;
    --surface-muted: #f8fafc;
    --surface-dark: #f1f5f9;
    --border: #e2e8f0;
    --border-hover: #cbd5e1;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --text-light: #94a3b8;
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --primary-light: #6366f1;
    --primary-bg: #eef2ff;
    --accent: #06b6d4;
    --success: #10b981;
    --info: #3b82f6;
    --danger: #ef4444;
    --shadow-soft: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-medium: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 8px;
    --radius-lg: 12px;
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Editor Wrapper */
.markdown-editor-wrapper {
    display: flex;
    flex-direction: column;
    gap: 24px;
    margin-bottom: 40px;
}

/* Editor Card */
.editor-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-soft);
    overflow: hidden;
    transition: var(--transition);
}

.editor-card:hover {
    box-shadow: var(--shadow-medium);
}

/* Editor Header */
.editor-header {
    background: var(--surface-muted);
    border-bottom: 1px solid var(--border);
    padding: 16px 20px;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 16px;
}

.header-left {
    display: flex;
    flex-direction: column;
    gap: 12px;
    flex: 1;
}

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

.editor-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-main);
    margin: 0;
}

.editor-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.action-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-main);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
}

.action-btn:hover {
    background: var(--surface-dark);
    border-color: var(--border-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-soft);
}

.action-btn-primary {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.action-btn-primary:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
}

.action-btn-secondary {
    background: var(--info);
    color: white;
    border-color: var(--info);
}

.action-btn-secondary:hover {
    background: #2563eb;
    border-color: #2563eb;
}

.action-btn i {
    font-size: 13px;
}

/* Toolbar */
.toolbar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: var(--surface-muted);
    border-bottom: 1px solid var(--border);
    flex-wrap: wrap;
    overflow-x: auto;
}

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

.toolbar-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    padding: 0;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
    font-size: 14px;
}

.toolbar-btn:hover {
    background: var(--surface-dark);
    border-color: var(--border-hover);
    color: var(--text-main);
    transform: translateY(-1px);
}

.toolbar-btn:active {
    transform: translateY(0);
}

.toolbar-separator {
    width: 1px;
    height: 24px;
    background: var(--border);
    margin: 0 4px;
}

.toolbar-spacer {
    flex: 1;
}

.layout-toggle {
    display: flex;
    gap: 4px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2px;
}

.layout-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 500;
    background: transparent;
    border: none;
    border-radius: calc(var(--radius) - 2px);
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
}

.layout-btn:hover {
    color: var(--text-main);
    background: var(--surface-dark);
}

.layout-btn.active {
    background: var(--primary);
    color: white;
}

.layout-label {
    display: none;
}

/* Editor Layout */
.editor-layout {
    display: flex;
    min-height: 500px;
    height: 600px;
    background: var(--surface);
}

.editor-pane,
.preview-pane {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.editor-pane {
    border-right: 1px solid var(--border);
}

.pane-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 16px;
    background: var(--surface-muted);
    border-bottom: 1px solid var(--border);
}

.pane-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.pane-title i {
    font-size: 12px;
}

.mobile-toggle-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 500;
    color: var(--primary);
    background: var(--primary-bg);
    border: 1px solid var(--primary);
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
}

.mobile-toggle-btn:hover {
    background: var(--primary);
    color: white;
}

/* Markdown Input */
.markdown-input {
    flex: 1;
    width: 100%;
    padding: 20px;
    
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-main);
    background: var(--surface);
    border: none;
    outline: none;
    resize: none;
    overflow-y: auto;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.markdown-input::placeholder {
    color: var(--text-light);
}

/* Preview Content */
.preview-content {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    background: var(--surface);
    line-height: 1.7;
    color: var(--text-main);
}

.preview-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--text-light);
    text-align: center;
}

.preview-placeholder i {
    font-size: 48px;
    margin-bottom: 16px;
    opacity: 0.5;
}

.preview-placeholder p {
    font-size: 16px;
    margin: 0;
}

/* GitHub-style Markdown Preview */
.preview-content h1 {
    padding-bottom: 0.3em;
    font-size: 2em;
    font-weight: 600;
    border-bottom: 1px solid var(--border);
    margin-top: 24px;
    margin-bottom: 16px;
}

.preview-content h2 {
    padding-bottom: 0.3em;
    font-size: 1.5em;
    font-weight: 600;
    border-bottom: 1px solid var(--border);
    margin-top: 24px;
    margin-bottom: 16px;
}

.preview-content h3 {
    font-size: 1.25em;
    font-weight: 600;
    margin-top: 24px;
    margin-bottom: 16px;
}

.preview-content h4,
.preview-content h5,
.preview-content h6 {
    font-size: 1em;
    font-weight: 600;
    margin-top: 16px;
    margin-bottom: 8px;
}

.preview-content p {
    margin-bottom: 16px;
}

.preview-content code {
    background-color: rgba(27, 31, 35, 0.05);
    border-radius: 4px;
    font-size: 85%;
    margin: 0;
    padding: 0.2em 0.4em;
    
}

.preview-content pre {
    background-color: #f6f8fa;
    border-radius: 6px;
    font-size: 85%;
    line-height: 1.45;
    overflow: auto;
    padding: 16px;
    margin-bottom: 16px;
}

.preview-content pre code {
    background: transparent;
    padding: 0;
    margin: 0;
    font-size: 100%;
}

.preview-content blockquote {
    border-left: 0.25em solid var(--border);
    color: var(--text-muted);
    padding: 0 1em;
    margin: 16px 0;
}

.preview-content ul,
.preview-content ol {
    margin-bottom: 16px;
    padding-left: 2em;
}

.preview-content li {
    margin-bottom: 4px;
}

.preview-content table {
    border-collapse: collapse;
    border-spacing: 0;
    width: 100%;
    margin: 16px 0;
    display: block;
    overflow-x: auto;
}

.preview-content table th,
.preview-content table td {
    border: 1px solid var(--border);
    padding: 6px 13px;
}

.preview-content table th {
    background-color: var(--surface-muted);
    font-weight: 600;
}

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

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

.preview-content img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius);
    margin: 16px 0;
}

.preview-content hr {
    border: none;
    border-top: 1px solid var(--border);
    margin: 24px 0;
}

/* Status Bar */
.status-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 16px;
    background: var(--surface-muted);
    border-top: 1px solid var(--border);
    font-size: 12px;
    flex-wrap: wrap;
    gap: 12px;
}

.status-group {
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.status-item {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-muted);
}

.status-item i {
    font-size: 11px;
    opacity: 0.7;
}

.status-value {
    font-weight: 600;
    color: var(--text-main);
}

.status-label {
    color: var(--text-muted);
}

/* Settings Dropdown */
.settings-dropdown {
    position: relative;
}

.settings-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    padding: 0;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
    font-size: 16px;
}

.settings-toggle:hover {
    background: var(--surface-dark);
    border-color: var(--border-hover);
    color: var(--text-main);
    transform: translateY(-1px);
    box-shadow: var(--shadow-soft);
}

.settings-toggle.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.settings-menu {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    width: 280px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: var(--transition);
    z-index: 1000;
    max-height: 500px;
    overflow-y: auto;
}

.settings-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.settings-menu-header {
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
    background: var(--surface-muted);
}

.settings-menu-header h4 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-main);
    margin: 0;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.settings-menu-body {
    padding: 8px;
}

.settings-menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 2px;
}

.settings-menu-item:hover {
    background: var(--surface-muted);
}

.settings-menu-item .setting-checkbox {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: var(--primary);
    flex-shrink: 0;
}

.settings-menu-item .setting-label {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    color: var(--text-main);
    cursor: pointer;
    flex: 1;
}

.settings-menu-item .setting-label i {
    font-size: 14px;
    color: var(--text-muted);
    width: 18px;
    text-align: center;
}

.settings-menu-item .setting-label span {
    flex: 1;
}

.settings-menu-divider {
    height: 1px;
    background: var(--border);
    margin: 8px 0;
}

/* Mobile Responsive */
@media (max-width: 767px) {
    .editor-layout {
        flex-direction: column;
        height: auto;
        min-height: 400px;
    }

    .editor-pane {
        border-right: none;
        border-bottom: 1px solid var(--border);
        min-height: 300px;
    }

    .preview-pane {
        min-height: 300px;
    }

    .editor-pane.hidden,
    .preview-pane.hidden {
        display: none;
    }

    .mobile-toggle-btn {
        display: flex !important;
    }

    .layout-toggle {
        display: none;
    }

    .toolbar {
        padding: 10px 12px;
    }

    .toolbar-btn {
        width: 32px;
        height: 32px;
        font-size: 12px;
    }

    .editor-actions {
        width: 100%;
    }

    .action-btn {
        flex: 1;
        justify-content: center;
        min-width: 0;
    }

    .btn-label {
        display: none;
    }

    .status-bar {
        flex-direction: column;
        align-items: flex-start;
        padding: 12px;
    }

    .status-group {
        width: 100%;
        justify-content: space-between;
    }

    .header-left {
        width: 100%;
    }

    .editor-actions {
        width: 100%;
    }

    .settings-menu {
        width: 260px;
        right: 0;
    }

    .editor-header {
        flex-direction: column;
        align-items: stretch;
    }

    .header-right {
        align-self: flex-end;
        margin-top: 12px;
    }
}

@media (max-width: 480px) {
    .editor-card {
        border-radius: 0;
        margin-left: -15px;
        margin-right: -15px;
        border-left: none;
        border-right: none;
    }

    .markdown-input {
        padding: 16px;
        font-size: 13px;
    }

    .preview-content {
        padding: 16px;
        font-size: 14px;
    }
}

/* Layout Modes */
.editor-layout.layout-edit .preview-pane {
    display: none;
}

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

.editor-layout.layout-preview .editor-pane {
    display: none;
}

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

/* Scrollbar Styling */
.markdown-input::-webkit-scrollbar,
.preview-content::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

.markdown-input::-webkit-scrollbar-track,
.preview-content::-webkit-scrollbar-track {
    background: var(--surface-muted);
}

.markdown-input::-webkit-scrollbar-thumb,
.preview-content::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

.markdown-input::-webkit-scrollbar-thumb:hover,
.preview-content::-webkit-scrollbar-thumb:hover {
    background: var(--border-hover);
}

/* Dark Mode */
.markdown-dark-mode .editor-card {
    background: #1e293b;
    border-color: #334155;
}

.markdown-dark-mode .editor-header {
    background: #0f172a;
    border-color: #334155;
}

.markdown-dark-mode .toolbar {
    background: #0f172a;
    border-color: #334155;
}

.markdown-dark-mode .markdown-input {
    background: #1e293b;
    color: #e2e8f0;
}

.markdown-dark-mode .preview-content {
    background: #1e293b;
    color: #e2e8f0;
}

.markdown-dark-mode .pane-header {
    background: #0f172a;
    border-color: #334155;
}

.markdown-dark-mode .pane-title {
    color: #94a3b8;
}

.markdown-dark-mode .status-bar {
    background: #0f172a;
    border-color: #334155;
}

.markdown-dark-mode .preview-content h1,
.markdown-dark-mode .preview-content h2 {
    border-color: #334155;
}

.markdown-dark-mode .preview-content code {
    background-color: rgba(255, 255, 255, 0.1);
}

.markdown-dark-mode .preview-content pre {
    background-color: #0f172a;
}

.markdown-dark-mode .preview-content blockquote {
    border-color: #334155;
    color: #94a3b8;
}

.markdown-dark-mode .preview-content table th,
.markdown-dark-mode .preview-content table td {
    border-color: #334155;
}

.markdown-dark-mode .preview-content table th {
    background-color: #0f172a;
}

.markdown-dark-mode .settings-menu {
    background: #1e293b;
    border-color: #334155;
}

.markdown-dark-mode .settings-menu-header {
    background: #0f172a;
    border-color: #334155;
}

.markdown-dark-mode .settings-menu-item:hover {
    background: #0f172a;
}

.markdown-dark-mode .settings-menu-item .setting-label {
    color: #e2e8f0;
}

.markdown-dark-mode .settings-menu-item .setting-label i {
    color: #94a3b8;
}

/* Line Numbers */
.markdown-input.show-line-numbers {
    counter-reset: line;
    padding-left: 50px;
    position: relative;
}

.markdown-input.show-line-numbers::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 45px;
    background: var(--surface-muted);
    border-right: 1px solid var(--border);
    pointer-events: none;
}

.markdown-dark-mode .markdown-input.show-line-numbers::before {
    background: #0f172a;
    border-color: #334155;
}