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

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --bg-color: #f3f4f6;
    --chat-bg: #ffffff;
    --text-color: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --user-message-bg: #2563eb;
    --user-message-text: #ffffff;
    --bot-message-bg: #f3f4f6;
    --bot-message-text: #1f2937;
    --error-color: #ef4444;
    --success-color: #10b981;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 1rem;
}

.chat-container {
    width: 100%;
    max-width: 800px;
    height: 90vh;
    max-height: 700px;
    background-color: var(--chat-bg);
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* Header */
.chat-header {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chat-header h1 {
    font-size: 1.25rem;
    font-weight: 600;
}

.status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--text-secondary);
}

.status.online .status-dot {
    background-color: var(--success-color);
}

.status.offline .status-dot {
    background-color: var(--error-color);
}

/* Messages */
.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.message {
    display: flex;
    max-width: 80%;
}

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

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

.message-content {
    padding: 0.75rem 1rem;
    border-radius: 1rem;
    line-height: 1.5;
    word-wrap: break-word;
}

.message.user .message-content {
    background-color: var(--user-message-bg);
    color: var(--user-message-text);
    border-bottom-right-radius: 0.25rem;
}

.message.bot .message-content {
    background-color: var(--bot-message-bg);
    color: var(--bot-message-text);
    border-bottom-left-radius: 0.25rem;
}

.message.error .message-content {
    background-color: #fef2f2;
    color: var(--error-color);
    border: 1px solid #fecaca;
}

/* Typing indicator */
.typing-indicator {
    display: flex;
    gap: 0.25rem;
    padding: 0.75rem 1rem;
    background-color: var(--bot-message-bg);
    border-radius: 1rem;
    border-bottom-left-radius: 0.25rem;
    align-self: flex-start;
}

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

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

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

@keyframes typing {
    0%, 100% {
        opacity: 0.4;
        transform: scale(1);
    }
    50% {
        opacity: 1;
        transform: scale(1.2);
    }
}

/* Input */
.chat-input {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border-color);
}

.chat-input form {
    display: flex;
    gap: 0.75rem;
}

.chat-input input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

.chat-input input:focus {
    border-color: var(--primary-color);
}

.chat-input input:disabled {
    background-color: var(--bg-color);
    cursor: not-allowed;
}

.chat-input button {
    padding: 0.75rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background-color 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.chat-input button:hover:not(:disabled) {
    background-color: var(--primary-hover);
}

.chat-input button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.chat-input button svg {
    width: 20px;
    height: 20px;
}

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

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

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

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

/* Responsive */
@media (max-width: 640px) {
    body {
        padding: 0;
    }

    .chat-container {
        height: 100vh;
        max-height: none;
        border-radius: 0;
    }

    .message {
        max-width: 90%;
    }
}