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

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --bg-color: #0f172a;
    --surface-color: #1e293b;
    --surface-hover: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --border-color: #334155;
    --success-color: #10b981;
    --error-color: #ef4444;
    --bot-bg: #1e3a8a;
    --user-bg: #059669;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial', sans-serif;
    background: linear-gradient(135deg, var(--bg-color) 0%, #1e293b 100%);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 1000px;
    height: 90vh;
    background: var(--surface-color);
    border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    padding: 20px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
}

.logo h1 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 4px;
}

.logo p {
    font-size: 14px;
    opacity: 0.9;
}

.status {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    background: rgba(255, 255, 255, 0.1);
    padding: 8px 16px;
    border-radius: 20px;
}

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

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

/* Chat Container */
.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 30px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.chat-container::-webkit-scrollbar {
    width: 8px;
}

.chat-container::-webkit-scrollbar-track {
    background: var(--bg-color);
}

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

.chat-container::-webkit-scrollbar-thumb:hover {
    background: var(--surface-hover);
}

/* Messages */
.message {
    display: flex;
    gap: 12px;
    max-width: 85%;
    animation: slideIn 0.3s ease;
}

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

.bot-message {
    align-self: flex-start;
}

.user-message {
    align-self: flex-end;
    flex-direction: row-reverse;
}

.message-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
    background: var(--surface-hover);
}

.message-content {
    flex: 1;
}

.message-text {
    background: var(--surface-hover);
    padding: 16px 20px;
    border-radius: 16px;
    line-height: 1.6;
    word-wrap: break-word;
}

.bot-message .message-text {
    background: var(--bot-bg);
    border-bottom-left-radius: 4px;
}

.user-message .message-text {
    background: var(--user-bg);
    border-bottom-right-radius: 4px;
}

.welcome-message .message-text {
    background: linear-gradient(135deg, #1e3a8a, #1e40af);
}

.welcome-message h3 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #fbbf24;
}

.welcome-message ul {
    margin: 12px 0;
    padding-left: 20px;
}

.welcome-message li {
    margin: 6px 0;
}

.welcome-message .examples {
    margin-top: 16px;
    padding-top: 16px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 14px;
    opacity: 0.9;
}

.message-text strong {
    color: #fbbf24;
}

.message-text code {
    background: rgba(0, 0, 0, 0.3);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
}

.message-text pre {
    background: rgba(0, 0, 0, 0.3);
    padding: 12px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 12px 0;
}

/* Loading indicator */
.typing-indicator {
    display: flex;
    gap: 6px;
    padding: 16px 20px;
    background: var(--bot-bg);
    border-radius: 16px;
    border-bottom-left-radius: 4px;
    width: fit-content;
}

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

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

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

@keyframes typing {
    0%, 60%, 100% {
        transform: translateY(0);
        opacity: 0.7;
    }
    30% {
        transform: translateY(-10px);
        opacity: 1;
    }
}

/* Input Container */
.input-container {
    background: var(--bg-color);
    padding: 20px 30px;
    border-top: 1px solid var(--border-color);
}

.input-wrapper {
    display: flex;
    gap: 12px;
    background: var(--surface-hover);
    border-radius: 12px;
    padding: 12px;
    align-items: flex-end;
}

#messageInput {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-size: 16px;
    resize: none;
    max-height: 120px;
    font-family: inherit;
    line-height: 1.5;
}

#messageInput::placeholder {
    color: var(--text-secondary);
    opacity: 0.6;
}

.send-button {
    width: 44px;
    height: 44px;
    border-radius: 8px;
    border: none;
    background: var(--primary-color);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    flex-shrink: 0;
}

.send-button:hover {
    background: var(--secondary-color);
    transform: scale(1.05);
}

.send-button:active {
    transform: scale(0.95);
}

.send-button:disabled {
    background: var(--border-color);
    cursor: not-allowed;
    transform: none;
}

.input-footer {
    margin-top: 8px;
    text-align: center;
}

.hint {
    font-size: 12px;
    color: var(--text-secondary);
    opacity: 0.6;
}

/* Error Message */
.error-message {
    background: var(--error-color);
    color: white;
    padding: 12px 20px;
    border-radius: 8px;
    margin: 10px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-content {
    background: var(--surface-color);
    padding: 30px;
    border-radius: 16px;
    max-width: 500px;
    width: 90%;
}

.modal-content h2 {
    margin-bottom: 20px;
}

.modal-content input {
    width: 100%;
    padding: 12px;
    background: var(--surface-hover);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 16px;
    margin: 20px 0;
}

.modal-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
}

.btn-primary, .btn-secondary {
    padding: 12px 24px;
    border-radius: 8px;
    border: none;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.2s;
}

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

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

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

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

/* Responsive */
@media (max-width: 768px) {
    .container {
        height: 100vh;
        border-radius: 0;
    }
    
    .header {
        padding: 15px 20px;
    }
    
    .logo h1 {
        font-size: 20px;
    }
    
    .chat-container {
        padding: 20px 15px;
    }
    
    .message {
        max-width: 90%;
    }
    
    .input-container {
        padding: 15px 20px;
    }
}