:root {
    --bg: #0a0a0a;
    --text: #f0f0f0;
    --dim: #666;
    --font-display: 'Inter', sans-serif;
    --font-mono: 'Space Mono', monospace;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-display);
    min-height: 100vh;
}

/* Masthead */
.masthead {
    padding: 3rem;
    text-align: center;
}

.masthead h1 {
    font-size: clamp(2.5rem, 8vw, 5rem);
    font-weight: 900;
    line-height: 1;
    letter-spacing: -0.04em;
    text-transform: uppercase;
}

.accent {
    -webkit-text-stroke: 2px var(--text);
    color: transparent;
}

/* Card Grid */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
    padding: 0 3rem 3rem;
    max-width: 1400px;
    margin: 0 auto;
}

/* Card */
.card {
    position: relative;
    aspect-ratio: 1 / 1;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    overflow: hidden;
    text-decoration: none;
    color: var(--text);
    cursor: pointer;
    animation: cardFadeIn 0.5s ease both;
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: border-color 0.3s, box-shadow 0.3s, transform 0.3s;
}

.card:hover {
    border-color: var(--card-accent);
    box-shadow: 0 0 30px color-mix(in srgb, var(--card-accent) 30%, transparent),
        inset 0 0 60px color-mix(in srgb, var(--card-accent) 5%, transparent);
    transform: translateY(-4px);
}

@keyframes cardFadeIn {
    from {
        opacity: 0;
        transform: translateY(20px) scale(0.97);
    }

    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* Card Inner - Flip/Reveal */
.card-inner {
    width: 100%;
    height: 100%;
    position: relative;
}

/* Front Face */
.card-front {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    transition: opacity 0.3s ease;
}

.card-id {
    position: absolute;
    top: 1rem;
    left: 1.2rem;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--dim);
}

.card-abbr {
    font-size: clamp(3rem, 5vw, 5rem);
    font-weight: 900;
    letter-spacing: -0.05em;
    opacity: 0.15;
    transition: opacity 0.3s, color 0.3s;
    text-transform: uppercase;
}

.card:hover .card-abbr {
    opacity: 0.08;
}

.card-status {
    position: absolute;
    bottom: 1rem;
    right: 1.2rem;
    font-family: var(--font-mono);
    font-size: 0.6rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--dim);
}

/* Back Face - Revealed on Hover */
.card-back {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 2rem;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.card:hover .card-back {
    opacity: 1;
    transform: translateY(0);
}

.card-title {
    font-size: 1.3rem;
    font-weight: 800;
    margin-bottom: 0.8rem;
    letter-spacing: -0.02em;
    color: var(--card-accent);
}

.card-desc {
    font-size: 0.85rem;
    line-height: 1.5;
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 1rem;
}

.card-tech {
    display: flex;
    gap: 0.3rem;
    flex-wrap: wrap;
    margin-bottom: 1.2rem;
}

.tag {
    font-family: var(--font-mono);
    font-size: 0.6rem;
    padding: 0.15rem 0.4rem;
    border: 1px solid var(--card-accent);
    color: var(--card-accent);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.card-cta {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--card-accent);
    letter-spacing: 0.1em;
}

/* Footer */
.site-footer {
    display: flex;
    justify-content: space-between;
    padding: 2rem 3rem;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    font-family: var(--font-mono);
    font-size: 0.8rem;
}

.footer-link {
    color: var(--dim);
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    transition: color 0.2s;
}

.footer-link:hover {
    color: var(--text);
}

/* Mobile */
@media (max-width: 768px) {
    .masthead {
        padding: 2rem 1.5rem;
    }

    .card-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
        padding: 0 1rem 2rem;
    }

    .card {
        aspect-ratio: auto;
        border-left: 3px solid var(--card-accent);
    }

    /* Hide the watermark front face */
    .card-front {
        display: none;
    }

    /* Always show full content on mobile */
    .card-back {
        position: relative;
        opacity: 1;
        transform: none;
        padding: 1.5rem;
    }

    .card-title {
        font-size: 1.1rem;
    }

    .card-desc {
        font-size: 0.85rem;
    }

    .card-cta {
        font-size: 0.75rem;
    }

    .site-footer {
        flex-direction: column;
        gap: 1rem;
        padding: 1.5rem;
        text-align: center;
    }
}