/* Pulse Animation */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

/* Bounce Animation */
@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

/* Fade In Animation */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* Slide Up Animation */
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Type Writer Animation */
@keyframes typing {
    from {
        width: 0;
    }
    to {
        width: 100%;
    }
}

/* Envelope Open Animation */
@keyframes envelopeShake {
    0%, 100% {
        transform: scale(1.05) rotateZ(0deg);
    }
    25% {
        transform: scale(1.05) rotateZ(-2deg);
    }
    75% {
        transform: scale(1.05) rotateZ(2deg);
    }
}

.envelope.opening {
    animation: envelopeShake 0.6s ease;
}

/* Apply animations to elements */
.content {
    animation: slideUp 0.8s ease;
}

h1 {
    animation: fadeIn 1s ease;
}

.gif {
    animation: fadeIn 1.2s ease;
}

.button-group {
    animation: slideUp 1s ease;
}

.envelope-section {
    animation: fadeIn 1s ease;
}