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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.chat-container {
    width: 90%;
    max-width: 600px;
    height: 80vh;
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.chat-header {
    background: #4f46e5;
    color: white;
    padding: 20px;
    text-align: center;
}

.chat-header h1 {
    font-size: 1.5rem;
    font-weight: 600;
}

.chat-messages {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.message {
    max-width: 80%;
    padding: 12px 16px;
    border-radius: 18px;
    word-wrap: break-word;
}

.user-message {
    background: #4f46e5;
    color: white;
    align-self: flex-end;
    margin-left: auto;
}

.ai-message {
    background: #f3f4f6;
    color: #374151;
    align-self: flex-start;
}

.chat-input {
    display: flex;
    padding: 20px;
    border-top: 1px solid #e5e7eb;
    gap: 10px;
}

#messageInput {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid #d1d5db;
    border-radius: 24px;
    outline: none;
    font-size: 16px;
}

#messageInput:focus {
    border-color: #4f46e5;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

#sendButton {
    padding: 12px 24px;
    background: #4f46e5;
    color: white;
    border: none;
    border-radius: 24px;
    cursor: pointer;
    font-weight: 600;
    transition: background 0.2s;
}

#sendButton:hover {
    background: #4338ca;
}

#sendButton:disabled {
    background: #9ca3af;
    cursor: not-allowed;
}

.loading {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #6b7280;
    font-style: italic;
}

.loading::after {
    content: '';
    width: 12px;
    height: 12px;
    border: 2px solid #e5e7eb;
    border-top: 2px solid #4f46e5;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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