/* Core Styles */
body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
    background-color: #ffffff;
    color: #111827;
}

.glass {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(243, 244, 246, 1);
}

/* Skeleton Styles */
.skeleton {
    background: linear-gradient(90deg, #f3f4f6 25%, #f9fafb 50%, #f3f4f6 75%);
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s infinite linear;
}

@keyframes skeleton-loading {
    0% {
        background-position: 200% 0;
    }

    100% {
        background-position: -200% 0;
    }
}

/* Security: Passcode Masking */
.mask-disc {
    -webkit-text-security: disc;
    text-security: disc;
    /* Fallback for potential future standard */
}

/* Quiz Specifics */
.katex-display {
    margin: 1.2em 0 !important;
}

.katex {
    font-size: 1.1em;
    line-height: 1.5;
}

/* Image Transitions */
.quiz-image-container {
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.quiz-image-container:hover {
    transform: translateY(-2px);
}

/* Tier Themes & Accessibility */
button:focus-visible,
input:focus-visible {
    outline: 2px solid #6366f1;
    outline-offset: 2px;
}

[class*="tier-"] {
    --tier-color: #94a3b8;
    --tier-bg: #f8fafc;
}

.tier-bronze {
    --tier-color: #cd7f32;
    --tier-bg: #fffaf5;
}

.tier-silver {
    --tier-color: #94a3b8;
    --tier-bg: #f8fafc;
}

.tier-gold {
    --tier-color: #fbbf24;
    --tier-bg: #fffdf0;
}

.tier-platinum {
    --tier-color: #2dd4bf;
    --tier-bg: #f0fdfa;
}

.tier-diamond {
    --tier-color: #818cf8;
    --tier-bg: #f5f3ff;
}

.tier-bg-accent {
    background-color: var(--tier-bg);
}

.tier-text-accent {
    color: var(--tier-color);
}

.tier-border-accent {
    border-color: var(--tier-color);
}

/* Cat Sprites & Animations */
.cat-sprite {
    width: 36px;
    height: 36px;
    background-image: url('assets/cats.png');
    background-size: 108px 108px;
    background-repeat: no-repeat;
    display: inline-block;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.cat-0 {
    background-position: 0 0;
}

.cat-1 {
    background-position: -36px 0;
}

.cat-2 {
    background-position: -72px 0;
}

.cat-3 {
    background-position: 0 -36px;
}

.cat-4 {
    background-position: -36px -36px;
}

.cat-5 {
    background-position: -72px -36px;
}

.cat-6 {
    background-position: 0 -72px;
}

.cat-7 {
    background-position: -36px -72px;
}

.cat-8 {
    background-position: -72px -72px;
}

.animate-float {
    animation: float 3s ease-in-out infinite;
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0);
    }

    50% {
        transform: translateY(-10px);
    }
}