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

:root {
    --primary-color: #f37f1f;
    --dark-bg: #1e1e1e;
    --light-bg: #2a2a2a;
    --border-color: #444;
    --text-color: #e0e0e0;
    --accent-color: #ff9f1c;
}

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

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    text-align: center;
    margin-bottom: 30px;
    padding: 20px 0;
    border-bottom: 2px solid var(--primary-color);
}

header h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 8px;
}

header .subtitle {
    color: var(--accent-color);
    font-size: 0.95rem;
}

main {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.models-section {
    background: var(--light-bg);
    padding: 20px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
}

.models-section h2 {
    margin-bottom: 15px;
    color: var(--primary-color);
}

.models-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 10px;
}

.model-tag {
    background: var(--dark-bg);
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-color);
}

.model-tag:hover {
    border-color: var(--primary-color);
    background: rgba(243, 127, 31, 0.1);
}

.loading {
    color: var(--accent-color);
    text-align: center;
    padding: 20px;
}

.chat-section {
    display: flex;
    flex-direction: column;
    flex: 1;
    gap: 15px;
}

.chat-box {
    background: var(--light-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    flex: 1;
    overflow-y: auto;
    min-height: 300px;
}

.messages {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.message {
    display: flex;
    gap: 10px;
    animation: slideIn 0.3s ease-out;
}

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

.message.user {
    justify-content: flex-end;
}

.message-content {
    max-width: 70%;
    padding: 12px 16px;
    border-radius: 8px;
    word-wrap: break-word;
}

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

.message.assistant .message-content {
    background: var(--dark-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

.message-sender {
    font-size: 0.75rem;
    color: var(--accent-color);
    margin-bottom: 4px;
}

.input-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.form-group {
    display: flex;
    gap: 10px;
}

.form-group:first-child {
    width: 100%;
}

.model-select {
    flex: 1;
    padding: 12px;
    background: var(--light-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
}

.model-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(243, 127, 31, 0.1);
}

.form-group:last-child {
    width: 100%;
}

#message-input {
    flex: 1;
    padding: 12px;
    background: var(--light-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    border-radius: 6px;
    font-size: 1rem;
}

#message-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(243, 127, 31, 0.1);
}

.send-btn {
    padding: 12px 24px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.3s ease;
}

.send-btn:hover {
    background: var(--accent-color);
}

.send-btn:active {
    transform: scale(0.98);
}

.send-btn:disabled {
    background: var(--border-color);
    cursor: not-allowed;
    opacity: 0.5;
}

footer {
    text-align: center;
    padding: 20px 0;
    border-top: 1px solid var(--border-color);
    margin-top: 30px;
    font-size: 0.85rem;
    color: var(--accent-color);
}

/* Loading animation */
.typing-indicator {
    display: flex;
    gap: 4px;
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent-color);
    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% {
        opacity: 0.5;
        transform: translateY(0);
    }
    30% {
        opacity: 1;
        transform: translateY(-10px);
    }
}

/* Responsive design */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }

    .message-content {
        max-width: 85%;
    }

    .models-grid {
        grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    }

    .form-group {
        flex-direction: column;
    }
}