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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

.header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

.chat-container {
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    overflow: hidden;
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 500px;
}

.chat-messages {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    max-height: 400px;
    background: #f8f9fa;
}

.message {
    margin-bottom: 20px;
    display: flex;
    flex-direction: column;
}

.user-message {
    align-items: flex-end;
}

.assistant-message {
    align-items: flex-start;
}

.message-content {
    max-width: 70%;
    padding: 15px 20px;
    border-radius: 20px;
    word-wrap: break-word;
    line-height: 1.5;
}

.user-message .message-content {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-bottom-right-radius: 5px;
}

.assistant-message .message-content {
    background: white;
    border: 1px solid #e1e5e9;
    border-bottom-left-radius: 5px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.message-time {
    font-size: 0.8rem;
    color: #666;
    margin-top: 5px;
    padding: 0 10px;
}

.chat-input-container {
    padding: 20px;
    background: white;
    border-top: 1px solid #e1e5e9;
}

.input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

#messageInput {
    flex: 1;
    padding: 15px 20px;
    border: 2px solid #e1e5e9;
    border-radius: 25px;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.3s ease;
}

#messageInput:focus {
    border-color: #667eea;
}

.send-button {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.2s ease;
}

.send-button:hover {
    transform: scale(1.05);
}

.send-button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.input-actions {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.action-button {
    background: #f8f9fa;
    border: 1px solid #e1e5e9;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.action-button:hover {
    background: #e9ecef;
    border-color: #667eea;
}

.session-info {
    text-align: center;
    margin-top: 20px;
    color: white;
    opacity: 0.8;
    font-size: 0.9rem;
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    display: none;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    z-index: 1000;
}

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

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading-overlay p {
    color: white;
    font-size: 1.1rem;
}

/* Responsive design */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .message-content {
        max-width: 85%;
    }
    
    .input-actions {
        justify-content: center;
    }
}

/* Scrollbar styling */
.chat-messages::-webkit-scrollbar {
    width: 6px;
}

.chat-messages::-webkit-scrollbar-track {
    background: #f1f1f1;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: #c1c1c1;
    border-radius: 3px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: #a8a8a8;
}