body {
    font-family: 'Inter', sans-serif;
}

.category-card {
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

/* Style to highlight the selected category card */
.category-card.selected {
    transform: translateY(-5px);
    box-shadow: 0 0 0 3px #4f46e5; /* Indigo ring */
    outline: none;
}

.answer-btn {
    transition: background-color 0.2s ease-in-out, border-color 0.2s ease-in-out, color 0.2s ease-in-out;
}

.answer-btn.selected {
    background-color: #e0e7ff;
    border-color: #4f46e5;
    color: #4f46e5;
}

.answer-btn.correct {
    background-color: #d1fae5;
    border-color: #10b981;
    color: #065f46;
}

.answer-btn.incorrect {
    background-color: #fee2e2;
    border-color: #ef4444;
    color: #991b1b;
}

#timer-bar {
    transition: width 0.5s linear;
}

/* Custom styles for the dropdown */
#difficulty-select {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3E%3Cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3E%3C/svg%3E");
    background-position: right 0.5rem center;
    background-repeat: no-repeat;
    background-size: 1.5em 1.5em;
    padding-right: 2.5rem;
}