/* ===================================
   ANIMACIONES PREMIUM
   =================================== */

/* === FADE IN === */
.fade-in {
    animation: fadeIn 1s ease-in-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

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

.fade-in-delay {
    animation: fadeIn 1s ease-in-out 0.3s both;
}

/* === FADE IN ON SCROLL === */
.fade-in-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* === RIPPLE EFFECT === */
.btn {
    position: relative;
    overflow: hidden;
}

.btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:active::after {
    width: 300px;
    height: 300px;
    opacity: 0;
}

/* === HOVER GLOW === */
.book-card {
    position: relative;
}

.book-card::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 12px;
    padding: 2px;
    background: linear-gradient(135deg, var(--secondary), var(--secondary-light));
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.book-card:hover::before {
    opacity: 1;
}

/* === PULSE === */
@keyframes pulse {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.7;
    }
}

.pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* === SLIDE IN === */
@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* === SCALE === */
@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }

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