body {
    font-family: 'Inter', sans-serif;
    background-color: #0c0a18;
    position: relative;
    overflow-x: hidden;
}

/* Animated Nebula Background */
body::before,
body::after {
    content: '';
    position: absolute;
    inset: -150px;
    z-index: -1;
    background-repeat: no-repeat;
    animation: move-nebula 45s infinite linear;
}

body::before {
    background-image:
        radial-gradient(ellipse at 33% 45%, #5a2a88, transparent),
        radial-gradient(ellipse at 80% 30%, #2a5a88, transparent),
        radial-gradient(ellipse at 60% 80%, #882a5a, transparent);
    opacity: 0.3;
}

body::after {
    background-image:
        radial-gradient(ellipse at 20% 70%, #2a885a, transparent),
        radial-gradient(ellipse at 50% 25%, #885a2a, transparent),
        radial-gradient(ellipse at 90% 65%, #2a8888, transparent);
    animation-direction: reverse;
    animation-duration: 35s;
    opacity: 0.3;
}

@keyframes move-nebula {
    0% {
        transform: rotate(0deg) translateX(10%) translateY(5%) scale(1);
    }

    50% {
        transform: rotate(180deg) translateX(-15%) translateY(-10%) scale(1.2);
    }

    100% {
        transform: rotate(360deg) translateX(10%) translateY(5%) scale(1);
    }
}

.perspective-container {
    perspective: 1000px;
}

.nexus-card {
    transform-style: preserve-3d;
    transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94), box-shadow 0.3s ease, border 0.3s ease;
}

.perspective-container:hover .nexus-card {
    transform: rotateY(var(--rotateY)) rotateX(var(--rotateX)) scale3d(1.05, 1.05, 1.05);
}

.warframe-glare {
    position: relative;
    overflow: hidden;
}

.warframe-glare::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    background: linear-gradient(110deg, rgba(255, 255, 255, 0) 40%, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0) 60%);
    transform: translateX(-100%);
    animation: glare-animation 3s infinite ease-in-out;
}

@keyframes glare-animation {

    0% {
        transform: translateX(-100%);
    }

    50% {
        transform: translateX(100%);
    }

    100% {
        transform: translateX(100%);
    }
}

/* Card Level Styles */
.level-2-border {
    box-shadow: 0 0 15px rgba(124, 58, 237, 0.7);
    /* Purple pulse */
    border: 2px solid rgba(124, 58, 237, 0.8);
}

.level-3-border {
    /* EPIC/MASTERED Card Styling */
    border: 2px solid;
    border-image-slice: 1;
    border-width: 2px;
    border-image-source: linear-gradient(to left, #f7b733, #fc4a1a);
    animation: epic-glow 2s infinite alternate;
}

@keyframes epic-glow {

    from {
        box-shadow: 0 0 5px #fc4a1a, 0 0 10px #f7b733;
    }

    to {
        box-shadow: 0 0 20px #fc4a1a, 0 0 30px #f7b733;
    }
}

/* Card Flip Styles */
.modal-card-inner {
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.modal-card.is-flipped .modal-card-inner {
    transform: rotateY(180deg);
}

.modal-card-front,
.modal-card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
}

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

/* Quiz Styles */
.quiz-option {
    transition: background-color 0.2s;
}

.quiz-option.selected {
    background-color: #4c1d95;
    /* Dark purple */
}

.quiz-option.correct {
    background-color: #166534;
    /* Green */
}

.quiz-option.incorrect {
    background-color: #991b1b;
    /* Red */
}