body { font-family: 'Inter', sans-serif; }
.math-display { overflow-x: auto; padding: 0.5rem 0; }

/* Loading Spinner */
.loader {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #4f46e5;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
}

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

/* Animations */
.animate-fade-in {
    animation: fadeIn 0.3s ease-out;
}

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