.fade-in-section {
    opacity: 0;
    transform: translateY(80px) scale(0.9);
    transition: opacity 1.2s cubic-bezier(0.25, 0.8, 0.25, 1), transform 1.2s cubic-bezier(0.25, 0.8, 0.25, 1);
    position: relative;
    z-index: 1;
}

.fade-in-section.is-visible {
    opacity: 1;
    transform: translateY(0) scale(1);
}

.btn-primary {
    background-color: #007BFF;
    transition: all 0.6s cubic-bezier(0.25, 0.8, 0.25, 1), box-shadow 0.3s ease-out;
    position: relative;
    z-index: 11;
    border: none;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    padding: 16px 40px;
    border-radius: 50px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    overflow: hidden;
    text-transform: uppercase;
    font-weight: 700;
    letter-spacing: 1.5px;
    color: #ffffff;
}

.btn-primary:hover {
    background-color: #0056b3;
    transform: translateY(-8px) scale(1.05);
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: all 0.7s cubic-bezier(0.25, 0.8, 0.25, 1);
    z-index: -1;
}

.btn-primary:hover::before {
    left: 100%;
}

@keyframes pulseGlowInitial {
    0% {
        box-shadow: 0 0 5px rgba(0, 123, 255, 0.4), 0 0 10px rgba(0, 123, 255, 0.2);
    }
    50% {
        box-shadow: 0 0 20px rgba(0, 123, 255, 0.9), 0 0 40px rgba(0, 123, 255, 0.7);
    }
    100% {
        box-shadow: 0 0 5px rgba(0, 123, 255, 0.4), 0 0 10px rgba(0, 123, 255, 0.2);
    }
}

.btn-primary.pulsating-initial {
    animation: pulseGlowInitial 2.5s ease-in-out infinite alternate;
}

.card:hover, .btn-primary.neon-glow-active, .nav-link.neon-glow-active {
    box-shadow: 0 0 15px 6px rgba(0, 123, 255, 0.8),
                0 0 30px 12px rgba(0, 123, 255, 0.5);
}

.card::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at center, rgba(255, 255, 255, 0.15) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 0.5s ease-out;
    transform: rotate(0deg);
}

.card:hover::after {
    opacity: 1;
    animation: cardLight 4s linear infinite;
}

@keyframes cardLight {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

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