/* ===================================
   MINIMALIST MODERN DESIGN - CHAT CENTRIC
   =================================== */

:root {
    /* Refined Color Palette */
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-light: #dbeafe;
    
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;
    
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    
    /* Enhanced Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Modern Radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    
    /* Subtle Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.05);
    
    /* Smooth Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Theme */
body.dark-theme {
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    
    --border-color: #334155;
    --border-light: #1e293b;
}

/* ===================================
   BASE STYLES
   =================================== */

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    transition: background-color var(--transition-base), color var(--transition-base);
}

/* ===================================
   MINIMAL HEADER
   =================================== */

.header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    transition: all var(--transition-base);
}

.header-content {
    max-width: 1600px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo-icon {
    width: 36px;
    height: 36px;
    /*background: linear-gradient(135deg, var(--primary), var(--primary-hover));*/
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.logo-icon i {
    font-size: 1.25rem;
}

.logo-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.logo-subtitle {
    display: none; /* Minimalist - hide subtitle */
}

.header-actions {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

/* Language Selector - Minimal */
.language-selector {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.language-selector:hover {
    border-color: var(--primary);
    background: var(--bg-secondary);
}

.language-select {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    outline: none;
}

/* ===================================
   CHAT-CENTRIC LAYOUT
   =================================== */

.container {
    max-width: 1600px;
    margin: 0 auto;
    padding: var(--spacing-xl);
    min-height: calc(100vh - 64px);
}

.main-grid {
    display: grid;
    grid-template-columns: 320px 1fr 320px;
    gap: var(--spacing-lg);
    height: calc(100vh - 120px);
    animation: fadeInUp 0.4s ease;
}

/* Responsive adjustments */
@media (max-width: 1400px) {
    .main-grid {
        grid-template-columns: 280px 1fr 280px;
    }
}

@media (max-width: 1200px) {
    .main-grid {
        grid-template-columns: 1fr;
        height: auto;
    }
}

/* ===================================
   SIDE PANELS (Collapsible)
   =================================== */

.side-panel {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    transition: all var(--transition-base);
}

.side-panel.collapsed {
    width: 48px;
    min-width: 48px;
}

.side-panel-header {
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--border-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.side-panel-title {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.side-panel.collapsed .side-panel-title {
    display: none;
}

.side-panel-content {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-md);
}

.side-panel.collapsed .side-panel-content {
    display: none;
}

/* ===================================
   CHAT PANEL (CENTRAL FOCUS)
   =================================== */

.chat-panel {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}

.chat-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chat-header-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.chat-avatar {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.chat-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.chat-subtitle {
    font-size: 0.813rem;
    color: var(--text-muted);
}

.chat-header-right {
    display: flex;
    gap: var(--spacing-xs);
}

/* Chat Messages - Clean & Spacious */
.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-2xl);
    background: var(--bg-secondary);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.chat-messages::-webkit-scrollbar {
    width: 6px;
}

.chat-messages::-webkit-scrollbar-track {
    background: transparent;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* Message Bubbles - Modern & Clean */
.message {
    display: flex;
    gap: var(--spacing-md);
    animation: messageSlide 0.3s ease;
    max-width: 85%;
}

.message.user {
    margin-left: auto;
    flex-direction: row-reverse;
}

.message-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
}

.message.user .message-avatar {
    background: var(--primary);
    color: white;
}

.message.assistant .message-avatar {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

.message-bubble {
    flex: 1;
}

.message-header {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.message-content {
    background: var(--bg-primary);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    color: var(--text-primary);
    line-height: 1.6;
    word-wrap: break-word;
}

.message.user .message-content {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

/* Message Sources - Subtle */
.message-sources {
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-sm);
    border-top: 1px solid var(--border-light);
}

.message-sources-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.source-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.813rem;
    color: var(--primary);
    text-decoration: none;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.source-link:hover {
    background: var(--primary-light);
}

/* Chat Input - Clean & Modern */
.chat-input-container {
    padding: var(--spacing-lg);
    background: var(--bg-primary);
    border-top: 1px solid var(--border-light);
}

.input-wrapper {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

#chatInput {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.938rem;
    outline: none;
    transition: all var(--transition-fast);
    resize: none;
    min-height: 48px;
    max-height: 120px;
}

#chatInput:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

#chatInput::placeholder {
    color: var(--text-muted);
}

/* Send Button - Prominent */
#sendBtn {
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    transition: all var(--transition-fast);
    flex-shrink: 0;
}

#sendBtn:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

#sendBtn:active {
    transform: translateY(0);
}

/* ===================================
   BUTTONS - MINIMAL & MODERN
   =================================== */

.btn {
    padding: var(--spacing-xs) var(--spacing-md);
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-primary);
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 500;
    font-size: 0.875rem;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
}

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

.btn-icon {
    padding: var(--spacing-xs);
    width: 32px;
    height: 32px;
    justify-content: center;
}

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

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

/* ===================================
   ANIMATIONS
   =================================== */

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes messageSlide {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ===================================
   UTILITIES
   =================================== */

.glass-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

/* Hide scrollbar but keep functionality */
.no-scrollbar::-webkit-scrollbar {
    display: none;
}

.no-scrollbar {
    -ms-overflow-style: none;
    scrollbar-width: none;
}

/* ===================================
   UPLOAD SECTION
   =================================== */

.upload-section {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: calc(100vh - 120px);
}

.upload-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-3xl);
    text-align: center;
    max-width: 600px;
    width: 100%;
    box-shadow: var(--shadow-lg);
}

.upload-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-xl);
    background: var(--primary-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 2rem;
}

.upload-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.upload-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-2xl);
}

.upload-zone {
    padding: var(--spacing-2xl);
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    background: var(--bg-secondary);
    cursor: pointer;
    transition: all var(--transition-base);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
}

.upload-zone:hover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.upload-zone.dragover {
    border-color: var(--primary);
    background: var(--primary-light);
    transform: scale(1.02);
}

.upload-zone i {
    font-size: 2rem;
    color: var(--text-muted);
}

.upload-zone p {
    color: var(--text-primary);
    font-weight: 500;
}

.upload-zone span {
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* Loading State */
.loading-state {
    text-align: center;
    padding: var(--spacing-3xl);
}

.loader {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
}

.loader-circle {
    width: 12px;
    height: 12px;
    background: var(--primary);
    border-radius: 50%;
    animation: bounce 1.4s infinite ease-in-out both;
}

.loader-circle:nth-child(1) {
    animation-delay: -0.32s;
}

.loader-circle:nth-child(2) {
    animation-delay: -0.16s;
}

@keyframes bounce {
    0%, 80%, 100% {
        transform: scale(0);
    }
    40% {
        transform: scale(1);
    }
}

.loading-text {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* ===================================
   SIDE PANELS - DETAILED
   =================================== */

.mindmap-container {
    width: 100%;
    height: 400px;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    overflow: hidden;
    margin-bottom: var(--spacing-md);
}

#mindmapCanvas {
    width: 100%;
    height: 100%;
    cursor: grab;
}

#mindmapCanvas:active {
    cursor: grabbing;
}

.mindmap-controls {
    display: flex;
    gap: var(--spacing-xs);
    justify-content: center;
}

/* Documents List */
.documents-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--border-light);
}

.document-count {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.documents-actions {
    display: flex;
    gap: var(--spacing-xs);
}

.files-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.file-item {
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-fast);
    cursor: pointer;
}

.file-item:hover {
    border-color: var(--primary);
    transform: translateX(4px);
}

.file-item.selected {
    background: var(--primary-light);
    border-color: var(--primary);
}

.file-checkbox {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.file-icon {
    color: var(--primary);
    font-size: 1.25rem;
}

.file-info {
    flex: 1;
    min-width: 0;
}

.file-name {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-size {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.file-status {
    font-size: 0.75rem;
    color: var(--success);
}

.delete-file-btn {
    color: var(--danger);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.file-item:hover .delete-file-btn {
    opacity: 1;
}

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

.btn-danger:hover {
    background: #dc2626;
    border-color: #dc2626;
}

/* ===================================
   NODE DETAILS PANEL (Overlay)
   =================================== */

.node-details-panel {
    position: fixed;
    top: 0;
    right: -400px;
    width: 400px;
    height: 100vh;
    background: var(--bg-primary);
    border-left: 1px solid var(--border-color);
    box-shadow: var(--shadow-xl);
    z-index: 1000;
    transition: right var(--transition-slow);
    display: flex;
    flex-direction: column;
}

.node-details-panel.active {
    right: 0;
}

.panel-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.panel-header h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.panel-content {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-lg);
}

/* ===================================
   MODAL
   =================================== */

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 999;
    animation: fadeIn 0.2s ease;
}

.modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    z-index: 1000;
    width: 90%;
    max-width: 600px;
    animation: scaleIn 0.2s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

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

.modal-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.modal-body {
    padding: var(--spacing-lg);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.938rem;
    outline: none;
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.form-group textarea {
    resize: vertical;
}

.modal-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-light);
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-sm);
}

/* ===================================
   NOTIFICATIONS
   =================================== */

.notifications {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.notification {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-left: 3px solid var(--primary);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    box-shadow: var(--shadow-lg);
    min-width: 320px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(100%);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.notification.success {
    border-left-color: var(--success);
}

.notification.error {
    border-left-color: var(--danger);
}

.notification.warning {
    border-left-color: var(--warning);
}

.notification-content {
    color: var(--text-primary);
    font-size: 0.875rem;
}

/* ===================================
   WELCOME MESSAGE
   =================================== */

.welcome-message {
    text-align: center;
    padding: var(--spacing-3xl);
    max-width: 500px;
    margin: auto;
}

.welcome-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--spacing-lg);
    background: var(--primary-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 1.5rem;
}

.welcome-message h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.welcome-message p {
    font-size: 1rem;
    color: var(--text-secondary);
}

/* ===================================
   RESPONSIVE DESIGN
   =================================== */

@media (max-width: 1200px) {
    .container {
        padding: var(--spacing-md);
    }
    
    .main-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
        height: auto;
    }
    
    .side-panel {
        height: 400px;
    }
    
    .chat-panel {
        height: 600px;
    }
}

@media (max-width: 768px) {
    .header-content {
        padding: 0 var(--spacing-md);
    }
    
    .logo-title {
        font-size: 1rem;
    }
    
    .upload-card {
        padding: var(--spacing-2xl);
    }
    
    .chat-messages {
        padding: var(--spacing-lg);
    }
    
    .node-details-panel {
        width: 100%;
        right: -100%;
    }
    
    .modal {
        width: 95%;
        max-height: 90vh;
        overflow-y: auto;
    }
}

/* ===================================
   RTL SUPPORT
   =================================== */

body.rtl {
    direction: rtl;
}

body.rtl .main-grid {
    direction: rtl;
}

body.rtl .message.user {
    flex-direction: row;
}

body.rtl .message.assistant {
    flex-direction: row-reverse;
}

body.rtl .file-item:hover {
    transform: translateX(-4px);
}

body.rtl .node-details-panel {
    left: -400px;
    right: auto;
    border-left: none;
    border-right: 1px solid var(--border-color);
}

body.rtl .node-details-panel.active {
    left: 0;
}