/* ============================================
   VIMANIA V4 — Animations & Micro-interactions
   Scroll-reveal, nav glass, skeleton loading.
   ============================================ */

/* ---- Scroll Reveal: fade-up ---- */
.fade-up {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
                transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-up.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* Staggered delays for card grids */
.fade-up.delay-1 { transition-delay: 0.06s; }
.fade-up.delay-2 { transition-delay: 0.12s; }
.fade-up.delay-3 { transition-delay: 0.18s; }
.fade-up.delay-4 { transition-delay: 0.24s; }

/* ---- Scroll Reveal: fade-in (legacy compat) ---- */
.fade-in {
    opacity: 0;
    transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-in.revealed {
    opacity: 1;
}

/* ---- Nav Glass Enhancement ---- */
.nav.scrolled,
.header.scrolled {
    background: var(--glass-heavy);
    -webkit-backdrop-filter: blur(16px) saturate(1.6);
    backdrop-filter: blur(16px) saturate(1.6);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.15);
}

/* ---- Skeleton Loading ---- */
.skeleton {
    position: relative;
    overflow: hidden;
    background: var(--bg-base);
    border-radius: var(--radius-lg, 12px);
}

.skeleton::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(
        90deg,
        transparent 0%,
        rgba(0, 0, 0, 0.03) 40%,
        rgba(0, 0, 0, 0.06) 50%,
        rgba(0, 0, 0, 0.03) 60%,
        transparent 100%
    );
    animation: shimmer 1.8s ease-in-out infinite;
}

.skeleton.loaded::after {
    animation: none;
    opacity: 0;
    transition: opacity 0.3s ease;
}

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

/* Skeleton variants */
.skeleton-card {
    height: 240px;
}

.skeleton-line {
    height: 14px;
    border-radius: 4px;
    margin-bottom: 8px;
}

.skeleton-line.short {
    width: 60%;
}

.skeleton-line.medium {
    width: 80%;
}

/* ---- Reduced Motion ---- */
@media (prefers-reduced-motion: reduce) {
    .fade-up,
    .fade-in {
        opacity: 1;
        transform: none;
        transition: none;
    }

    .skeleton::after {
        animation: none;
    }

    .nav.scrolled,
    .header.scrolled {
        transition: none;
    }
}

/* ---- Mobile: faster reveals ---- */
@media (max-width: 640px) {
    .fade-up {
        transform: translateY(16px);
        transition-duration: 0.4s;
    }

    .fade-up.delay-1,
    .fade-up.delay-2,
    .fade-up.delay-3,
    .fade-up.delay-4 {
        transition-delay: 0s;
    }
}