/* ===== CSS Variables ===== */
:root {
    --color-bg-primary: #ffffff;
    --color-bg-secondary: #f8f9fa;
    --color-bg-tertiary: #f1f3f4;
    --color-bg-hover: #e8eaed;
    --color-bg-active: #d3d6da;
    
    --color-text-primary: #1f2937;
    --color-text-secondary: #6b7280;
    --color-text-muted: #9ca3af;
    
    --color-border: #e5e7eb;
    --color-border-light: #f3f4f6;
    
    --color-primary: #3b82f6;
    --color-primary-hover: #2563eb;
    --color-primary-light: #dbeafe;
    
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    
    --color-sidebar-bg: #f8f9fa;
    --color-sidebar-hover: #e8eaed;
    
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
    
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Courier New', monospace;
    
    --sidebar-width: 260px;
    --topbar-height: 56px;
    
    --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode */
body.dark {
    --color-bg-primary: #1a1a1a;
    --color-bg-secondary: #242424;
    --color-bg-tertiary: #2d2d2d;
    --color-bg-hover: #333333;
    --color-bg-active: #404040;
    
    --color-text-primary: #e4e4e7;
    --color-text-secondary: #a1a1aa;
    --color-text-muted: #71717a;
    
    --color-border: #3f3f46;
    --color-border-light: #333333;
    
    --color-sidebar-bg: #1f1f1f;
    --color-sidebar-hover: #2a2a2a;
}

/* ===== Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-sans);
    font-size: 14px;
    line-height: 1.6;
    color: var(--color-text-primary);
    background: var(--color-bg-primary);
    overflow: hidden;
}

/* ===== Auth Screen ===== */
.auth-screen {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.auth-container {
    background: white;
    padding: 40px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 400px;
}

.auth-header {
    text-align: center;
    margin-bottom: 30px;
}

.auth-header i {
    font-size: 48px;
    color: var(--color-primary);
    margin-bottom: 15px;
}

.auth-header h1 {
    font-size: 28px;
    margin-bottom: 5px;
}

.auth-header p {
    color: var(--color-text-secondary);
}

.auth-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.auth-hint {
    text-align: center;
    padding: 12px;
    background: var(--color-bg-secondary);
    border-radius: var(--radius-md);
    font-size: 13px;
    color: var(--color-text-secondary);
}

/* ===== App Layout ===== */
.app {
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

/* ===== Topbar ===== */
.topbar {
    height: var(--topbar-height);
    background: var(--color-bg-primary);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    gap: 20px;
}

.topbar-left,
.topbar-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.topbar-center {
    flex: 1;
    max-width: 600px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    font-size: 16px;
}

.logo i {
    color: var(--color-primary);
    font-size: 20px;
}

.search-bar {
    position: relative;
    width: 100%;
}

.search-bar input {
    width: 100%;
    padding: 8px 40px 8px 40px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-bg-secondary);
    transition: all var(--transition);
}

.search-bar input:focus {
    outline: none;
    border-color: var(--color-primary);
    background: var(--color-bg-primary);
}

.search-bar i {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-text-muted);
}

.search-bar kbd {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    padding: 2px 6px;
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 11px;
    color: var(--color-text-muted);
}

/* User Menu */
.user-menu {
    position: relative;
}

.user-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: none;
    background: var(--color-bg-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
}

.user-avatar:hover {
    background: var(--color-bg-hover);
}

.user-avatar i {
    font-size: 20px;
    color: var(--color-text-secondary);
}

.user-dropdown {
    display: none;
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    min-width: 220px;
    z-index: 1000;
}

.user-dropdown.active {
    display: block;
}

.user-info {
    padding: 12px 16px;
}

.user-name {
    font-weight: 600;
    margin-bottom: 2px;
}

.user-email {
    font-size: 12px;
    color: var(--color-text-secondary);
}

.user-dropdown a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 16px;
    color: var(--color-text-primary);
    text-decoration: none;
    transition: background var(--transition);
}

.user-dropdown a:hover {
    background: var(--color-bg-hover);
}

.dropdown-divider {
    height: 1px;
    background: var(--color-border);
    margin: 4px 0;
}

/* ===== Main Container ===== */
.main-container {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* ===== Sidebar ===== */
.sidebar {
    width: var(--sidebar-width);
    background: var(--color-sidebar-bg);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

.sidebar-header {
    padding: 16px;
    border-bottom: 1px solid var(--color-border);
}

.sidebar-nav {
    padding: 8px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 12px;
    margin: 2px 0;
    color: var(--color-text-secondary);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: all var(--transition);
}

.nav-item:hover {
    background: var(--color-sidebar-hover);
    color: var(--color-text-primary);
}

.nav-item.active {
    background: var(--color-primary-light);
    color: var(--color-primary);
    font-weight: 500;
}

.sidebar-section {
    padding: 16px 8px;
    border-top: 1px solid var(--color-border);
}

.sidebar-section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 8px 8px;
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.spaces-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.space-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 12px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition);
}

.space-item:hover {
    background: var(--color-sidebar-hover);
}

.space-item.active {
    background: var(--color-primary-light);
}

.space-item-icon {
    font-size: 16px;
}

.space-item-name {
    flex: 1;
    font-size: 14px;
}

/* ===== Content Area ===== */
.content {
    flex: 1;
    background: var(--color-bg-primary);
    overflow-y: auto;
}

.view {
    display: none;
}

.view.active {
    display: block;
}

.content-header {
    padding: 40px 60px;
    border-bottom: 1px solid var(--color-border);
}

.content-header h1 {
    font-size: 32px;
    margin-bottom: 8px;
}

.content-header p {
    color: var(--color-text-secondary);
    font-size: 16px;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    padding: 40px 60px;
}

.stat-card {
    background: var(--color-bg-secondary);
    padding: 24px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    text-align: center;
}

.stat-card i {
    font-size: 32px;
    color: var(--color-primary);
    margin-bottom: 12px;
}

.stat-value {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 4px;
}

.stat-label {
    color: var(--color-text-secondary);
    font-size: 13px;
}

/* Recent Activity */
.recent-activity {
    padding: 40px 60px;
}

.recent-activity h2 {
    font-size: 20px;
    margin-bottom: 20px;
}

.pages-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.page-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition);
}

.page-item:hover {
    background: var(--color-bg-hover);
    border-color: var(--color-primary);
}

/* Space Header */
.space-header {
    display: flex;
    align-items: center;
    gap: 20px;
}

.space-icon {
    font-size: 48px;
}

.header-actions {
    display: flex;
    gap: 12px;
}

/* Page Tree */
.page-tree {
    padding: 20px 60px;
}

.tree-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    margin: 2px 0;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition);
}

.tree-item:hover {
    background: var(--color-bg-hover);
}

.tree-item i {
    color: var(--color-text-muted);
}

.tree-children {
    margin-left: 24px;
}

/* Page Editor */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 60px;
    border-bottom: 1px solid var(--color-border);
}

.page-breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--color-text-secondary);
    font-size: 13px;
}

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

.page-editor {
    padding: 40px 60px;
    max-width: 900px;
    margin: 0 auto;
}

.page-title-input {
    width: 100%;
    font-size: 40px;
    font-weight: 700;
    border: none;
    padding: 12px 0;
    margin-bottom: 20px;
    background: transparent;
    color: var(--color-text-primary);
}

.page-title-input:focus {
    outline: none;
}

.editor-container {
    min-height: 400px;
    font-size: 16px;
    line-height: 1.7;
}

/* TipTap Editor Styles */
.ProseMirror {
    outline: none;
}

.ProseMirror h1 {
    font-size: 32px;
    font-weight: 700;
    margin: 24px 0 12px;
}

.ProseMirror h2 {
    font-size: 24px;
    font-weight: 600;
    margin: 20px 0 10px;
}

.ProseMirror h3 {
    font-size: 20px;
    font-weight: 600;
    margin: 16px 0 8px;
}

.ProseMirror p {
    margin: 8px 0;
}

.ProseMirror code {
    background: var(--color-bg-tertiary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.9em;
}

.ProseMirror pre {
    background: var(--color-bg-tertiary);
    padding: 16px;
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin: 16px 0;
}

.ProseMirror blockquote {
    border-left: 3px solid var(--color-primary);
    padding-left: 16px;
    margin: 16px 0;
    color: var(--color-text-secondary);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition);
}

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

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

.btn-secondary {
    background: var(--color-bg-secondary);
    color: var(--color-text-primary);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    background: var(--color-bg-hover);
}

.btn-block {
    width: 100%;
    justify-content: center;
}

.btn-icon,
.btn-icon-sm {
    padding: 8px;
    border: none;
    background: transparent;
    color: var(--color-text-secondary);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition);
}

.btn-icon-sm {
    padding: 4px;
}

.btn-icon:hover,
.btn-icon-sm:hover {
    background: var(--color-bg-hover);
    color: var(--color-text-primary);
}

/* ===== Forms ===== */
.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    font-size: 13px;
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="password"],
.form-group textarea {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-family: inherit;
    transition: all var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary);
}

/* ===== Modal ===== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 2000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--color-bg-primary);
    border-radius: var(--radius-lg);
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px;
    border-bottom: 1px solid var(--color-border);
}

.modal-header h2 {
    font-size: 20px;
}

.modal-close {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--color-text-secondary);
    font-size: 20px;
    padding: 4px;
}

.modal-body {
    padding: 20px;
    max-height: calc(90vh - 140px);
    overflow-y: auto;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 12px;
    padding: 20px;
    border-top: 1px solid var(--color-border);
}

/* ===== Utility Classes ===== */
.text-muted {
    color: var(--color-text-muted);
}

.text-secondary {
    color: var(--color-text-secondary);
}

.hidden {
    display: none !important;
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .sidebar {
        position: absolute;
        left: 0;
        top: var(--topbar-height);
        height: calc(100vh - var(--topbar-height));
        z-index: 100;
        transform: translateX(-100%);
        transition: transform var(--transition);
    }
    
    .sidebar.active {
        transform: translateX(0);
    }
    
    .content-header,
    .page-editor {
        padding-left: 20px;
        padding-right: 20px;
    }
}