/* --- DESIGN SYSTEM & SYSTEM VARIABLES --- */
:root {
    /* Color Palette */
    --pimo-pink-light: #fff5f6;
    --pimo-pink: #ffa5ab;
    --pimo-pink-dark: #da627d;
    --pimo-white: #ffffff;
    --pimo-gold: #e5c583;
    --pimo-gold-glow: rgba(229, 197, 131, 0.45);
    
    /* Romantic Velvet Rose Colors */
    --pimo-romantic-bg: radial-gradient(circle at center, #2e071c 0%, #15020c 60%, #0a0005 100%);
    
    /* Typography */
    --font-cormorant: 'Cormorant Garamond', serif;
    --font-outfit: 'Outfit', sans-serif;
    --font-inter: 'Inter', sans-serif;
    --font-serif: 'Playfair Display', serif;
    --font-great-vibes: 'Great Vibes', cursive;

    /* Shadows & Transitions */
    --shadow-soft: 0 10px 40px rgba(218, 98, 125, 0.08);
    --shadow-glass: 0 25px 70px rgba(0, 0, 0, 0.65);
    --shadow-gold-glow: 0 0 20px rgba(229, 197, 131, 0.35);
    --transition-smooth: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
    --transition-quick: all 0.25s ease;
}

/* --- BASE STYLES --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background: var(--pimo-romantic-bg);
    color: #f1f5f9;
    font-family: var(--font-inter);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
}

/* Typography Utility Classes */
.cormorant-font { font-family: var(--font-cormorant); }
.outfit-font { font-family: var(--font-outfit); }
.great-vibes-font { font-family: var(--font-great-vibes); }

/* Canvas Background for Particles, Flowers, and Butterflies */
#particles-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 100; /* SIT ON TOP: Butterflies will fly in front of all pages */
    pointer-events: none; /* Let all clicks pass through to the buttons/content */
}

/* Main Container */
#app-container {
    position: relative;
    width: 100%;
    height: 100%;
    z-index: 2;
    overflow: hidden;
}

/* --- PAGE SYSTEM --- */
.page {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition-smooth);
    transform: scale(0.97) translateY(10px);
    z-index: 2;
}

.page.active {
    opacity: 1;
    pointer-events: all;
    transform: scale(1) translateY(0);
    z-index: 10;
}

/* --- GLASS CONTAINER CARD --- */
.glass-card {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(20px) saturate(110%);
    -webkit-backdrop-filter: blur(20px) saturate(110%);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 30px;
    padding: 50px 40px;
    width: 90%;
    max-width: 460px;
    box-shadow: var(--shadow-glass);
    text-align: center;
    z-index: 15;
    position: relative;
}

/* --- PAGE 1: ENCRYPTED GATE (Classy Gold, Blush, White Theme) --- */
#page-1 {
    background: radial-gradient(circle at top right, #ffffff, #fff5f6 40%, #ffe3e7 100%);
    color: #334155;
}

#page-1 .glass-card {
    background: rgba(255, 255, 255, 0.78);
    border: 1.5px solid var(--pimo-gold);
    box-shadow: 0 15px 45px rgba(218, 98, 125, 0.12), var(--shadow-gold-glow);
}

#page-1 .decor-tulip {
    position: absolute;
    width: 220px;
    bottom: -40px;
    opacity: 0.95;
    z-index: 5;
    pointer-events: none;
    transition: var(--transition-smooth);
}

#page-1 .tulip-left {
    left: -40px;
    transform: rotate(10deg);
}

#page-1 .tulip-right {
    right: -40px;
    transform: rotate(-10deg) scaleX(-1);
}

#page-1 .lock-icon-wrapper {
    width: 80px;
    height: 80px;
    background: radial-gradient(circle, #fff 0%, #fff2f4 100%);
    border: 2px solid var(--pimo-gold);
    border-radius: 50%;
    margin: 0 auto 25px auto;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 8px 25px rgba(229, 197, 131, 0.35);
    animation: goldPulse 3s infinite;
}

#page-1 .lock-icon svg {
    width: 32px;
    height: 32px;
    stroke: var(--pimo-gold);
}

#page-1 .page-title {
    font-size: 2.5rem;
    font-weight: 400;
    color: #1e293b;
    margin-bottom: 8px;
    letter-spacing: 0.5px;
}

#page-1 .subtitle {
    font-size: 1.15rem;
    color: #64748b;
    margin-bottom: 35px;
    font-style: italic;
}

#page-1 .input-group {
    position: relative;
    margin-bottom: 30px;
    width: 100%;
}

#page-1 .input-group input {
    width: 100%;
    padding: 18px 20px;
    border: 1px solid rgba(229, 197, 131, 0.8);
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.95);
    font-family: var(--font-outfit);
    font-size: 1.25rem;
    color: #1e293b;
    text-align: center;
    letter-spacing: 3px;
    outline: none;
    transition: var(--transition-quick);
}

#page-1 .input-group input:focus {
    border-color: var(--pimo-pink-dark);
    box-shadow: 0 0 15px rgba(218, 98, 125, 0.2);
}

#page-1 .input-group label {
    position: absolute;
    top: -10px;
    left: 24px;
    background: #fff8f9;
    padding: 2px 10px;
    font-size: 0.75rem;
    font-family: var(--font-outfit);
    font-weight: 600;
    color: var(--pimo-pink-dark);
    border-radius: 4px;
    letter-spacing: 0.5px;
}

#page-1 .error-msg {
    color: #ef4444;
    font-family: var(--font-outfit);
    font-size: 0.85rem;
    font-weight: 500;
    margin-top: 8px;
    opacity: 0;
    height: 0;
    overflow: hidden;
    transition: var(--transition-quick);
}

#page-1 .error-msg.show {
    opacity: 1;
    height: auto;
    margin-top: 8px;
}

#page-1 .glow-btn {
    background: #1e293b;
    color: #ffffff;
    border: 1px solid var(--pimo-gold);
    padding: 18px 32px;
    border-radius: 16px;
    font-size: 1.05rem;
    font-weight: 500;
    letter-spacing: 1px;
    cursor: pointer;
    box-shadow: 0 6px 20px rgba(30, 41, 59, 0.2);
    display: inline-flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    width: 100%;
    transition: var(--transition-quick);
}

#page-1 .glow-btn:hover {
    transform: translateY(-2px);
    background: #0f172a;
    box-shadow: 0 8px 25px rgba(229, 197, 131, 0.35);
}

#page-1 .glow-btn .btn-arrow {
    width: 18px;
    height: 18px;
    stroke: var(--pimo-gold);
    transition: var(--transition-quick);
}

#page-1 .glow-btn:hover .btn-arrow {
    transform: translateX(4px);
}

@keyframes goldPulse {
    0% { box-shadow: 0 0 0 0 rgba(229, 197, 131, 0.5); }
    70% { box-shadow: 0 0 0 15px rgba(229, 197, 131, 0); }
    100% { box-shadow: 0 0 0 0 rgba(229, 197, 131, 0); }
}


/* --- PAGE 2: STATUTORY WARNING (Black and White Theme) --- */
#page-2 {
    background: radial-gradient(circle at center, #18181b 0%, #09090b 100%);
}

#page-2 .warning-card {
    border: 1px solid rgba(255, 255, 255, 0.15);
    background: rgba(0, 0, 0, 0.65);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.8), 0 0 25px rgba(255, 255, 255, 0.05);
}

#page-2 .warning-icon-wrapper {
    width: 60px;
    height: 60px;
    border: 2px solid #ffffff;
    border-radius: 50%;
    margin: 0 auto 20px auto;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.2);
    animation: bwPulse 2.5s infinite;
}

#page-2 .warning-icon-wrapper svg {
    width: 30px;
    height: 30px;
    stroke: #ffffff;
}

#page-2 h2 {
    color: #ffffff;
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 3px;
    margin-bottom: 25px;
}

#page-2 .black-box-warning {
    background: #000000;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 14px;
    padding: 26px;
    margin-bottom: 30px;
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.9);
}

#page-2 .warning-text {
    font-family: var(--font-serif);
    font-size: 1.1rem;
    line-height: 1.7;
    color: #f4f4f5;
    font-style: italic;
    letter-spacing: 0.5px;
}

#page-2 .warning-btn {
    background: #ffffff;
    color: #000000;
    border: 1px solid #ffffff;
    padding: 16px 36px;
    border-radius: 14px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(255, 255, 255, 0.1);
    transition: var(--transition-quick);
}

#page-2 .warning-btn:hover {
    background: #e4e4e7;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 255, 255, 0.2);
}

@keyframes bwPulse {
    0%, 100% { box-shadow: 0 0 8px rgba(255, 255, 255, 0.1); transform: scale(1); }
    50% { box-shadow: 0 0 20px rgba(255, 255, 255, 0.35); transform: scale(1.05); }
}


/* --- PAGE 3: CONFIRMATION GAME (UNCHANGED) --- */
#page-3 {
    background: radial-gradient(circle at center, #0c0d21 0%, #020207 100%);
}

#page-3 .confirmation-card {
    border: 1px solid rgba(0, 180, 216, 0.15);
    max-width: 480px;
}

#page-3 .question-title {
    font-size: 1.9rem;
    color: #e0f2fe;
    margin-bottom: 8px;
    text-shadow: 0 0 10px rgba(0, 180, 216, 0.2);
}

#page-3 .sub-question {
    font-size: 0.95rem;
    color: #94a3b8;
    margin-bottom: 40px;
}

#page-3 .options-wrapper {
    position: relative;
    min-height: 180px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

#page-3 .no-buttons-container {
    display: flex;
    gap: 20px;
    justify-content: center;
    align-items: center;
    width: 100%;
}

#page-3 .no-btn {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 14px 36px;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-quick);
}

#page-3 .no-btn:hover {
    background: rgba(239, 35, 60, 0.2);
    border-color: #ef233c;
}

#page-3 .no-btn.runaway {
    position: absolute;
    z-index: 50;
    transition: all 0.15s cubic-bezier(0.2, 0.8, 0.2, 1);
}

#page-3 .yes-button-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transform: translateY(20px);
    pointer-events: none;
    transition: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
    position: absolute;
    bottom: -10px;
    width: 100%;
}

#page-3 .yes-button-wrapper.reveal-yes {
    opacity: 1;
    transform: translateY(0);
    pointer-events: all;
}

#page-3 .reveal-hint {
    color: var(--pimo-pink);
    font-size: 0.9rem;
    margin-bottom: 8px;
    letter-spacing: 1px;
    font-weight: 600;
    animation: bounceText 1.5s infinite;
}

#page-3 .yes-btn {
    background: linear-gradient(135deg, #00f5d4 0%, #00bbf9 100%);
    color: #050b18;
    border: none;
    padding: 16px 40px;
    border-radius: 16px;
    font-size: 1.15rem;
    font-weight: 700;
    cursor: pointer;
    box-shadow: 0 8px 30px rgba(0, 245, 212, 0.35);
    transition: var(--transition-quick);
    display: inline-flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
}

#page-3 .yes-btn:hover {
    transform: scale(1.05) translateY(-2px);
    box-shadow: 0 12px 35px rgba(0, 245, 212, 0.55);
}

#page-3 .cute-caption-box {
    margin-top: 30px;
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.04);
    border-radius: 12px;
    font-size: 0.85rem;
    color: #94a3b8;
    min-height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}


/* --- PAGE 4: ROMANTIC VELVET FAIRYTALE LETTER (LAPTOP OPTIMIZED) --- */
#page-4 {
    background: var(--pimo-romantic-bg);
    overflow: hidden; /* Lock viewport height to 100vh on laptop */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 0;
    height: 100vh;
}

.castle-header-bg, .castle-footer-bg {
    width: 100%;
    text-align: center;
    pointer-events: none;
    opacity: 0.12;
    mix-blend-mode: screen;
    position: absolute;
    left: 0;
    z-index: 1;
}

.castle-header-bg {
    top: 20px;
}

.castle-footer-bg {
    bottom: 20px;
}

.castle-img {
    max-width: 260px;
    width: 40%;
    filter: drop-shadow(0 0 25px rgba(229, 197, 131, 0.25));
}

.castle-img-footer {
    max-width: 320px;
    width: 50%;
    filter: drop-shadow(0 0 25px rgba(229, 197, 131, 0.25));
}

/* FIXED CONTAINER VIEWPORT FOR LAPTOPS */
.letter-scroll-wrapper {
    width: 92%;
    max-width: 760px; /* Wider book-like screen layout */
    height: 82vh; /* Fix height relative to screen size (prevents infinite scrolling) */
    margin: 0 auto;
    padding: 0;
    position: relative;
    z-index: 10;
    display: flex;
    flex-direction: column;
}

.letter-container {
    background: rgba(18, 5, 12, 0.45); /* Velvet Rose Translucent base */
    backdrop-filter: blur(25px);
    -webkit-backdrop-filter: blur(25px);
    border: 1px solid rgba(255, 165, 171, 0.12); /* Rosy border outline */
    border-radius: 28px;
    padding: 50px 45px;
    box-shadow: 0 25px 70px rgba(0, 0, 0, 0.7), inset 0 0 40px rgba(218, 98, 125, 0.05);
    position: relative;
    overflow-y: auto; /* Internal scrolling within card */
    height: 100%;
    scrollbar-width: thin;
    scrollbar-color: var(--pimo-pink-dark) rgba(0, 0, 0, 0.1);
}

/* Custom Scrollbar Styling (Chrome/Edge/Safari) */
.letter-container::-webkit-scrollbar {
    width: 6px;
}

.letter-container::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.02);
    border-radius: 10px;
}

.letter-container::-webkit-scrollbar-thumb {
    background: var(--pimo-pink-dark);
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.letter-container::-webkit-scrollbar-thumb:hover {
    background: var(--pimo-pink);
}

/* Floating Corner Tulips */
.corner-tulip {
    position: absolute;
    width: 120px;
    opacity: 0.12;
    pointer-events: none;
}

.tulip-top-left {
    top: -15px;
    left: -15px;
    transform: rotate(35deg);
}

.tulip-top-right {
    top: -15px;
    right: -15px;
    transform: rotate(-35deg) scaleX(-1);
}

/* Titles */
.letter-title-section {
    text-align: center;
    margin-bottom: 45px;
}

.letter-title-section h1 {
    font-size: 3.5rem;
    color: var(--pimo-pink);
    text-shadow: 0 0 25px rgba(255, 165, 171, 0.35);
    margin-bottom: 12px;
}

.title-divider {
    font-size: 1.15rem;
    color: rgba(229, 197, 131, 0.3);
    letter-spacing: 8px;
    font-family: var(--font-cormorant);
}

/* Paragraph Cards */
.letter-paragraph-card {
    position: relative;
    margin-bottom: 45px;
    line-height: 1.85;
    font-size: 1.35rem; /* Larger, elegant novel font size */
    font-family: var(--font-cormorant);
    color: #f1f5f9;
    transition: var(--transition-smooth);
    opacity: 0.92;
}

.letter-paragraph-card:hover {
    transform: translateY(-1px);
    opacity: 1;
}

.paragraph-text {
    margin-bottom: 18px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.15);
    letter-spacing: 0.2px;
    text-align: justify;
}

/* --- INTEGRATED AUDIO PLAYERS --- */
.song-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(229, 197, 131, 0.2);
    border-radius: 16px;
    padding: 8px 18px;
    display: inline-flex;
    align-items: center;
    gap: 14px;
    max-width: 290px;
    transition: var(--transition-quick);
    margin-top: 8px;
    cursor: pointer;
}

.song-card:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: var(--pimo-pink);
    box-shadow: 0 4px 12px rgba(255, 165, 171, 0.1);
}

.song-card.playing {
    background: rgba(218, 98, 125, 0.12);
    border-color: var(--pimo-pink);
    box-shadow: 0 0 15px rgba(255, 165, 171, 0.15);
}

.play-pause-btn {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: none;
    background: linear-gradient(135deg, var(--pimo-pink) 0%, var(--pimo-pink-dark) 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    box-shadow: 0 3px 8px rgba(218, 98, 125, 0.25);
    transition: var(--transition-quick);
    flex-shrink: 0;
}

.play-pause-btn:hover {
    transform: scale(1.06);
}

.play-pause-btn svg {
    width: 14px;
    height: 14px;
    fill: white;
}

.play-pause-btn .hidden {
    display: none;
}

.song-info {
    display: flex;
    flex-direction: column;
    gap: 1px;
}

.song-title {
    font-size: 0.9rem;
    font-weight: 500;
    color: #e2e8f0;
    font-family: var(--font-outfit);
}

.audio-wave {
    display: flex;
    align-items: flex-end;
    gap: 2px;
    height: 9px;
    margin-top: 2px;
}

.audio-wave span {
    width: 2px;
    height: 100%;
    background-color: var(--pimo-pink);
    border-radius: 2px;
    transform-origin: bottom;
    transform: scaleY(0.2);
    transition: transform 0.2s ease;
}

.song-card.playing .audio-wave span {
    animation: wavePulse 0.8s ease infinite alternate;
}

.song-card.playing .audio-wave span:nth-child(1) { animation-delay: 0.1s; }
.song-card.playing .audio-wave span:nth-child(2) { animation-delay: 0.3s; }
.song-card.playing .audio-wave span:nth-child(3) { animation-delay: 0s; }
.song-card.playing .audio-wave span:nth-child(4) { animation-delay: 0.2s; }

@keyframes wavePulse {
    0% { transform: scaleY(0.2); }
    100% { transform: scaleY(1); }
}

/* --- STICKERS (Laptop Widescreen Responsive Alignment) --- */
.sticker-container {
    position: absolute;
    width: 80px;
    height: 80px;
    pointer-events: none;
    z-index: 5;
    opacity: 0.9;
}

.sticker-left {
    left: -100px;
    top: 25%;
}

.sticker-right {
    right: -100px;
    top: 45%;
}

.sticker-img {
    width: 100%;
    height: auto;
    filter: drop-shadow(0 8px 12px rgba(0, 0, 0, 0.45));
}

.minion-float {
    animation: minionFloatAnim 4s ease-in-out infinite alternate;
}

.olaf-wobble {
    animation: olafWobbleAnim 5s ease-in-out infinite alternate;
}

@keyframes minionFloatAnim {
    0% { transform: translateY(0) rotate(-3deg); }
    100% { transform: translateY(-10px) rotate(3deg); }
}

@keyframes olafWobbleAnim {
    0% { transform: scale(1) rotate(-4deg) translateY(0); }
    100% { transform: scale(1.02) rotate(4deg) translateY(-8px); }
}

/* Responsive adjustment: Pull stickers inside the text layout on smaller laptops or tablets */
@media (max-width: 980px) {
    .sticker-container {
        position: relative;
        display: inline-block;
        margin: 15px auto;
        left: auto;
        right: auto;
        top: auto;
        vertical-align: middle;
        text-align: center;
    }
    
    .letter-paragraph-card {
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    
    .paragraph-text {
        width: 100%;
    }
}

/* --- SIGN OFF SECTION --- */
.signoff-card {
    text-align: center;
    border-bottom: 1px solid rgba(255, 165, 171, 0.08);
    padding-bottom: 30px;
    margin-bottom: 40px;
}

.signoff-text {
    font-size: 3rem;
    color: var(--pimo-pink);
    margin-bottom: 20px;
    text-shadow: 0 0 15px rgba(255, 165, 171, 0.2);
}

.signature {
    font-size: 2.2rem;
}

.italic-sig {
    font-style: italic;
    color: #e2e8f0;
    letter-spacing: 1px;
}

/* --- BIRTHDAY CARD STYLING --- */
.birthday-divider {
    margin: 40px auto;
}

.birthday-card {
    text-align: left;
    padding-top: 20px;
}

.birthday-title {
    font-size: 3.5rem;
    color: var(--pimo-pink);
    text-align: center;
    margin-bottom: 25px;
    text-shadow: 0 0 25px rgba(255, 165, 171, 0.35);
}

.birthday-wishlist {
    list-style: none;
    padding-left: 5px;
    margin: 25px 0;
}

.birthday-wishlist li {
    font-size: 1.35rem;
    line-height: 1.8;
    color: #f1f5f9;
    margin-bottom: 18px;
    position: relative;
    padding-left: 32px;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
}

.gift-bullet {
    position: absolute;
    left: 0;
    top: 0;
    color: var(--pimo-pink);
    font-size: 1.1rem;
    text-shadow: 0 0 8px rgba(255, 165, 171, 0.4);
}

.highlight-text {
    color: var(--pimo-gold);
    font-weight: 600;
    text-shadow: 0 0 8px rgba(229, 197, 131, 0.2);
}

.new-year-wish {
    font-size: 1.45rem;
    font-style: italic;
    color: var(--pimo-pink);
    text-align: center;
    margin: 35px 0 25px 0;
    letter-spacing: 0.5px;
    text-shadow: 0 0 12px rgba(255, 165, 171, 0.2);
}

/* --- SLAP CONTAINER (BOTTOM OF DIARY SCROLL) --- */
.slap-container {
    margin-top: 45px;
    text-align: center;
    width: 100%;
}

.slap-btn {
    background: rgba(255, 255, 255, 0.03);
    border: 1px dashed rgba(229, 197, 131, 0.4);
    border-radius: 16px;
    padding: 16px 24px;
    color: #94a3b8;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition-quick);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 100%;
}

.slap-btn:hover {
    background: rgba(218, 98, 125, 0.08);
    border-style: solid;
    border-color: var(--pimo-pink);
    color: white;
    box-shadow: 0 5px 20px rgba(218, 98, 125, 0.15);
}

.slap-btn .hand-emoji {
    font-size: 1.2rem;
    transition: var(--transition-quick);
}

.slap-btn:hover .hand-emoji {
    transform: rotate(-25deg) scale(1.2);
}

.shake-screen {
    animation: screenShake 0.4s ease-out;
}

@keyframes screenShake {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    10% { transform: translate(-4px, -2px) rotate(-0.5deg); }
    30% { transform: translate(3px, 4px) rotate(0.5deg); }
    50% { transform: translate(-3px, -4px) rotate(-0.5deg); }
    70% { transform: translate(4px, 3px) rotate(0.5deg); }
    90% { transform: translate(-1px, 1px) rotate(-0.2deg); }
}

/* --- RESPONSIVE ADJUSTMENTS --- */
@media (max-width: 768px) {
    .letter-scroll-wrapper {
        margin: 20px auto;
        padding: 0;
        height: 86vh;
    }
    
    .letter-container {
        padding: 40px 20px;
        border-radius: 20px;
    }

    .letter-title-section h1 {
        font-size: 2.8rem;
    }

    .sticker-container {
        position: relative;
        display: block;
        margin: 20px auto;
        left: auto;
        right: auto;
        top: auto;
    }
}

@keyframes bounceText {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-4px); }
}