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

:root {
    --primary: #4F46E5;
    --primary-dark: #4338CA;
    --primary-light: #818CF8;
    --success: #10B981;
    --danger: #EF4444;
    --warning: #F59E0B;
    --bg: #F9FAFB;
    --surface: #FFFFFF;
    --border: #E5E7EB;
    --text: #111827;
    --text-light: #6B7280;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

.container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
.header {
    background: var(--surface);
    padding: 20px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

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

.logo h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text);
}

.status {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-light);
    font-size: 14px;
}

.status-indicator {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success);
    animation: pulse 2s infinite;
}

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

/* Main Content */
.main-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    min-height: calc(100vh - 160px);
}

/* Panels */
.panel {
    background: var(--surface);
    border-radius: 12px;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.panel-header {
    padding: 20px 30px;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.panel-header h2 {
    font-size: 18px;
    font-weight: 600;
}

.badge {
    background: var(--primary-light);
    color: white;
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

.panel-content {
    padding: 30px;
    flex: 1;
    overflow-y: auto;
}

/* Model Selector */
.model-selector-container {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
    padding: 16px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.model-selector-label {
    display: flex;
    align-items: center;
    gap: 8px;
    color: white;
    font-weight: 600;
    font-size: 14px;
    white-space: nowrap;
}

.model-selector {
    flex: 1;
    padding: 10px 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.95);
    color: var(--text);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    outline: none;
}

.model-selector:hover {
    background: white;
    border-color: rgba(255, 255, 255, 0.6);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.model-selector:focus {
    background: white;
    border-color: white;
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.3);
}

.model-indicator {
    background: rgba(255, 255, 255, 0.15);
    padding: 4px 12px;
    border-radius: 8px;
    font-size: 12px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Tabs */
.tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border);
}

.tab {
    background: none;
    border: none;
    padding: 12px 24px;
    cursor: pointer;
    color: var(--text-light);
    font-weight: 500;
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}

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

.tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Form Elements */
textarea, .input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-family: inherit;
    font-size: 14px;
    resize: vertical;
    transition: border-color 0.2s;
}

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

textarea {
    margin-bottom: 12px;
    background: var(--bg);
}

.input {
    margin-bottom: 16px;
}

/* Buttons */
.btn {
    background: var(--primary);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    font-size: 14px;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s;
    width: 100%;
    justify-content: center;
}

.btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

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

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-small {
    padding: 6px 12px;
    font-size: 12px;
    width: auto;
}

.btn-icon {
    font-size: 16px;
}

/* File Upload */
.file-upload-area {
    border: 2px dashed var(--border);
    border-radius: 8px;
    padding: 40px;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    margin-bottom: 20px;
}

.file-upload-area:hover {
    border-color: var(--primary);
    background: var(--bg);
}

.file-upload-area.drag-over {
    border-color: var(--primary);
    background: var(--primary-light);
    background-opacity: 0.1;
}

.file-upload-icon {
    font-size: 48px;
    margin-bottom: 12px;
}

.file-upload-hint {
    color: var(--text-light);
    font-size: 12px;
    margin-top: 8px;
}

.file-list {
    margin-bottom: 20px;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px;
    background: var(--bg);
    border-radius: 8px;
    margin-bottom: 8px;
}

.file-item-name {
    display: flex;
    align-items: center;
    gap: 8px;
}

.file-item-remove {
    background: var(--danger);
    color: white;
    border: none;
    padding: 4px 8px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
}

/* Upload History */
.upload-history {
    margin-top: 30px;
    padding-top: 30px;
    border-top: 1px solid var(--border);
}

.upload-history h3 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-light);
}

.history-list {
    max-height: 200px;
    overflow-y: auto;
}

.history-item {
    padding: 8px 12px;
    background: var(--bg);
    border-radius: 6px;
    margin-bottom: 6px;
    font-size: 13px;
}

.history-item-name {
    font-weight: 500;
}

.history-item-time {
    color: var(--text-light);
    font-size: 11px;
}

/* Chat Messages */
.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    background: var(--bg);
    border-radius: 8px;
    margin-bottom: 20px;
    min-height: 400px;
    max-height: calc(100vh - 450px);
}

.welcome-message {
    text-align: center;
    padding: 40px 20px;
}

.welcome-message h3 {
    font-size: 24px;
    margin-bottom: 12px;
}

.example-questions {
    margin-top: 24px;
}

.example-questions p {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 12px;
}

.example-q {
    display: block;
    margin: 8px auto;
    padding: 8px 16px;
    background: white;
    border: 1px solid var(--border);
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.2s;
}

.example-q:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.message {
    display: flex;
    gap: 12px;
    margin-bottom: 20px;
    animation: slideIn 0.3s ease;
}

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

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    flex-shrink: 0;
}

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

.bot-message .message-avatar {
    background: var(--success);
    color: white;
}

.message-content {
    flex: 1;
    background: white;
    padding: 12px 16px;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.message-text {
    font-size: 14px;
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.message-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
    margin-top: 8px;
    font-size: 11px;
    color: var(--text-light);
}

.message-sources {
    font-style: italic;
}

.message-model {
    padding: 2px 8px;
    background: rgba(0, 0, 0, 0.05);
    border-radius: 4px;
    font-weight: 600;
}

.message.loading .message-content {
    background: var(--bg);
}

.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 8px 0;
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--text-light);
    animation: typing 1.4s infinite;
}

.typing-indicator span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-indicator span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% {
        transform: translateY(0);
    }
    30% {
        transform: translateY(-10px);
    }
}

/* Chat Input */
.chat-input-container {
    display: flex;
    gap: 12px;
    align-items: flex-end;
}

.chat-input-container textarea {
    flex: 1;
    max-height: 120px;
    margin-bottom: 0;
}

.btn-send {
    width: auto;
    padding: 12px 20px;
    border-radius: 8px;
}

.chat-footer {
    margin-top: 12px;
    text-align: center;
}

.chat-footer small {
    color: var(--text-light);
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.loading-overlay.active {
    display: flex;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.loading-overlay p {
    position: absolute;
    margin-top: 80px;
    color: white;
    font-weight: 500;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 2000;
}

.toast {
    background: white;
    padding: 16px 20px;
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 300px;
    animation: slideInRight 0.3s ease;
}

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

.toast-success {
    border-left: 4px solid var(--success);
}

.toast-error {
    border-left: 4px solid var(--danger);
}

.toast-warning {
    border-left: 4px solid var(--warning);
}

.toast-icon {
    font-size: 20px;
}

.toast-content {
    flex: 1;
}

.toast-title {
    font-weight: 600;
    margin-bottom: 4px;
}

.toast-message {
    font-size: 13px;
    color: var(--text-light);
}

/* Responsive */
@media (max-width: 1200px) {
    .main-content {
        grid-template-columns: 1fr;
    }
    
    .chat-panel {
        min-height: 600px;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .header {
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
    
    .panel-content {
        padding: 20px;
    }
    
    .model-selector-container {
        flex-direction: column;
        gap: 8px;
    }
    
    .model-selector-label {
        width: 100%;
        justify-content: center;
    }
    
    .model-selector {
        width: 100%;
    }
}

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

::-webkit-scrollbar-track {
    background: var(--bg);
}

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

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