:root {
    --primary-color: #FF5722; /* Orange color from the image */
    --background-color: #FFFFFF; /* White background */
}

body {
    background-color: var(--background-color);
    color: var(--primary-color);
}

.flashcard {
    perspective: 1000px;
    height: 200px;
    cursor: pointer;
}

.flashcard-front,
.flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    transition: transform 0.6s;
    background-color: var(--background-color);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.flashcard-back {
    transform: rotateY(180deg);
}

.flashcard.flipped .flashcard-front {
    transform: rotateY(180deg);
}

.flashcard.flipped .flashcard-back {
    transform: rotateY(0deg);
}

.list-group-item {
    cursor: pointer;
    background-color: var(--background-color);
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.list-group-item.selected {
    background-color: var(--primary-color);
    color: var(--background-color);
}

.list-group-item.correct {
    background-color: #28a745;
    color: var(--background-color);
}

.list-group-item.incorrect {
    background-color: #dc3545;
    color: var(--background-color);
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: var(--background-color);
}

.btn-primary:hover {
    background-color: #E64A19; /* Darker shade of the primary color */
    border-color: #E64A19;
}

h1, h2, h3 {
    color: var(--primary-color);
}