/* Envelope Animations */
.envelope-wrapper {
    animation: envelopeFloat 3s ease-in-out infinite;
}

@keyframes envelopeFloat {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

.envelope-wrapper:hover {
    animation: none;
    transform: translateY(-5px) scale(1.05);
}

.envelope-wrapper:active {
    transform: translateY(-2px) scale(1.02);
}

/* Envelope Opening Animation */
.envelope.opening {
    pointer-events: none;
}

.envelope.opening .envelope-flap {
    transform: rotateX(-180deg);
    transition: transform 0.8s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

.envelope.opened .envelope-body {
    transform: translateY(-20px);
    opacity: 0.7;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

/* Letter Paper Animation */
.letter-paper {
    opacity: 0;
    transform: translateY(50px) scale(0.9);
    transition: opacity 0.6s ease 0.3s, transform 0.6s ease 0.3s;
}

.letter-paper.revealed {
    opacity: 1;
    transform: translateY(0) scale(1);
}

/* Fade In Animation */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* Slide Up Animation */
.slide-up {
    animation: slideUp 0.6s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Loading Spinner Animation */
@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

/* Character Text Animation */
.character-text {
    animation: fadeInScale 0.8s ease-out 0.5s both;
}

/* Fixed Message Text Animation (character와 동일한 애니메이션) */
.fixed-message-text {
    animation: fadeInScale 0.8s ease-out 0.5s both;
}

@keyframes fadeInScale {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Message Text Animation */
.message-text {
    animation: fadeInUp 0.8s ease-out 0.7s both;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* From Section Animation */
.from-section {
    animation: fadeIn 0.8s ease-out 0.9s both;
}

/* Smooth Transitions */
* {
    transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .envelope-wrapper {
        animation: none;
    }
}