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

body {
    font-family: 'Georgia', serif;
    overflow: hidden;
    background: #000;
    color: #fff;
    height: 100vh;
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

/* Page Management */
.page {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    opacity: 0;
    visibility: hidden;
    transition: opacity 1s ease-in-out, visibility 1s ease-in-out;
    z-index: 1;
}

.page.active {
    opacity: 1;
    visibility: visible;
    z-index: 2;
}

/* Cosmic Background */
.stars-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 30%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
                radial-gradient(circle at 80% 70%, rgba(255, 119, 198, 0.2) 0%, transparent 50%),
                radial-gradient(circle at 40% 80%, rgba(30, 144, 255, 0.3) 0%, transparent 50%),
                linear-gradient(135deg, #0c0c0c 0%, #1a1a2e 50%, #16213e 100%);
    animation: cosmic-shift 20s ease-in-out infinite;
}

@keyframes cosmic-shift {
    0%, 100% { transform: scale(1) rotate(0deg); }
    50% { transform: scale(1.05) rotate(0.5deg); }
}

.stars-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, #fff, transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.8), transparent),
        radial-gradient(1px 1px at 90px 40px, #fff, transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(255,255,255,0.6), transparent),
        radial-gradient(2px 2px at 160px 30px, #fff, transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: twinkle 3s ease-in-out infinite alternate;
}

@keyframes twinkle {
    0% { opacity: 0.7; }
    100% { opacity: 1; }
}

/* Floating Particles */
.floating-particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.floating-particles::before,
.floating-particles::after {
    content: '';
    position: absolute;
    width: 4px;
    height: 4px;
    background: radial-gradient(circle, rgba(255,255,255,0.8) 0%, transparent 70%);
    border-radius: 50%;
    animation: float 8s linear infinite;
}

.floating-particles::before {
    top: 10%;
    left: 20%;
    animation-delay: -2s;
}

.floating-particles::after {
    top: 60%;
    right: 30%;
    animation-delay: -5s;
}

@keyframes float {
    0% { transform: translateY(100vh) translateX(0); opacity: 0; }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% { transform: translateY(-100px) translateX(50px); opacity: 0; }
}

/* Landing Page Styles */
.landing-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100vh;
    text-align: center;
}

.saturn-container {
    margin-bottom: 40px;
}

.saturn-planet {
    position: relative;
    width: 200px;
    height: 200px;
    cursor: pointer;
    transition: transform 0.3s ease;
    animation: gentle-rotate 20s linear infinite;
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
}

.saturn-planet:hover {
    transform: scale(1.1);
}

@keyframes gentle-rotate {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.planet-body {
    width: 120px;
    height: 120px;
    background: radial-gradient(circle at 30% 30%, #ffeb3b, #ff9800, #8d6e63);
    border-radius: 50%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 0 40px rgba(255, 193, 7, 0.6),
                inset 0 0 20px rgba(0, 0, 0, 0.3);
    animation: planet-glow 2s ease-in-out infinite alternate;
}

@keyframes planet-glow {
    0% { box-shadow: 0 0 40px rgba(255, 193, 7, 0.6), inset 0 0 20px rgba(0, 0, 0, 0.3); }
    100% { box-shadow: 0 0 60px rgba(255, 193, 7, 0.8), inset 0 0 20px rgba(0, 0, 0, 0.3); }
}

.ring {
    position: absolute;
    border: 2px solid rgba(255, 193, 7, 0.6);
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) rotateX(75deg);
}

.ring-1 {
    width: 180px;
    height: 180px;
    border-width: 3px;
    animation: ring-glow 2s ease-in-out infinite alternate;
}

.ring-2 {
    width: 220px;
    height: 220px;
    border-width: 2px;
    animation: ring-glow 2s ease-in-out infinite alternate 0.5s;
}

.ring-3 {
    width: 260px;
    height: 260px;
    border-width: 1px;
    animation: ring-glow 2s ease-in-out infinite alternate 1s;
}

@keyframes ring-glow {
    0% { border-color: rgba(255, 193, 7, 0.4); }
    100% { border-color: rgba(255, 193, 7, 0.8); }
}

.landing-text h1 {
    font-size: 2rem;
    background: linear-gradient(45deg, #ffeb3b, #ff9800, #e91e63, #9c27b0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
    animation: text-shimmer 3s ease-in-out infinite;
    margin-bottom: 20px;
}

.click-instruction {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.9);
    text-shadow: 0 0 15px rgba(255, 255, 255, 0.4);
    animation: gentle-pulse 2s ease-in-out infinite;
    margin-top: 10px;
}

@keyframes gentle-pulse {
    0%, 100% { opacity: 0.7; transform: translateY(0); }
    50% { opacity: 1; transform: translateY(-2px); }
}

@keyframes text-shimmer {
    0%, 100% { opacity: 0.8; }
    50% { opacity: 1; }
}

/* Floating Comets */
.floating-comets {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.floating-comets::before,
.floating-comets::after {
    content: '';
    position: absolute;
    width: 6px;
    height: 6px;
    background: linear-gradient(45deg, #fff, #ffeb3b);
    border-radius: 50%;
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.8);
}

.floating-comets::before {
    top: 20%;
    right: 10%;
    animation: comet-trail 12s linear infinite;
}

.floating-comets::after {
    top: 70%;
    left: 15%;
    animation: comet-trail 15s linear infinite reverse;
}

@keyframes comet-trail {
    0% { transform: translate(0, 0); opacity: 0; }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% { transform: translate(-100vw, 50vh); opacity: 0; }
}

/* Planets Page */
.planets-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    height: 80vh;
    gap: 40px;
    padding: 20px;
}

.planet-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    transition: transform 0.3s ease, filter 0.3s ease;
    animation: planet-float 6s ease-in-out infinite;
}

.planet-item:nth-child(2) { animation-delay: -1s; }
.planet-item:nth-child(3) { animation-delay: -2s; }
.planet-item:nth-child(4) { animation-delay: -3s; }
.planet-item:nth-child(5) { animation-delay: -4s; }

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

.planet-item:hover {
    transform: scale(1.2) translateY(-10px);
    filter: brightness(1.3);
}

.planet-item.visited {
    opacity: 0.6;
    filter: grayscale(0.3);
}

.planet-image {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: 0 0 30px rgba(255, 255, 255, 0.4);
    transition: box-shadow 0.3s ease;
}

.planet-item:hover .planet-image {
    box-shadow: 0 0 50px rgba(255, 255, 255, 0.8);
}

.planet-name {
    margin-top: 15px;
    font-size: 1.2rem;
    color: #fff;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
}

.progress-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
}

#progress-text {
    font-size: 1.1rem;
    margin-bottom: 15px;
    color: rgba(255, 255, 255, 0.8);
}

.progress-dots {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transition: background 0.3s ease;
}

.dot.completed {
    background: #ffeb3b;
    box-shadow: 0 0 10px rgba(255, 235, 59, 0.6);
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1000;
}

.modal.active {
    display: flex;
    justify-content: center;
    align-items: center;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
}

.modal-content {
    background: linear-gradient(135deg, rgba(26, 26, 46, 0.95), rgba(22, 33, 62, 0.95));
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 30px;
    max-width: 500px;
    width: 90%;
    max-height: 70vh;
    overflow-y: auto;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    animation: modal-enter 0.3s ease-out;
    position: relative;
    z-index: 1001;
}

@keyframes modal-enter {
    0% { opacity: 0; transform: scale(0.8) translateY(50px); }
    100% { opacity: 1; transform: scale(1) translateY(0); }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.modal-header h3 {
    font-size: 1.5rem;
    color: #ffeb3b;
    text-shadow: 0 0 10px rgba(255, 235, 59, 0.5);
}

.modal-close {
    background: none;
    border: none;
    color: #fff;
    font-size: 24px;
    cursor: pointer;
    padding: 5px;
    transition: color 0.3s ease;
}

.modal-close:hover {
    color: #ffeb3b;
}

.modal-body p {
    font-size: 1.1rem;
    line-height: 1.6;
    color: #fff;
    text-align: center;
    font-style: italic;
}

/* Letter Page */
#letter-page {
    overflow-y: auto;
    background: radial-gradient(ellipse at center, rgba(138, 43, 226, 0.1) 0%, transparent 50%),
                radial-gradient(ellipse at 80% 20%, rgba(75, 0, 130, 0.15) 0%, transparent 50%),
                radial-gradient(ellipse at 20% 80%, rgba(25, 25, 112, 0.1) 0%, transparent 50%),
                linear-gradient(135deg, #0c0c0c 0%, #1a1a2e 50%, #16213e 100%);
    background-attachment: fixed;
}

#letter-page .stars-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    z-index: 0;
}

.galaxy-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: radial-gradient(ellipse at center, rgba(138, 43, 226, 0.1) 0%, transparent 50%),
                radial-gradient(ellipse at 80% 20%, rgba(75, 0, 130, 0.15) 0%, transparent 50%),
                radial-gradient(ellipse at 20% 80%, rgba(25, 25, 112, 0.1) 0%, transparent 50%);
    animation: galaxy-drift 30s linear infinite;
    z-index: 0;
}

@keyframes galaxy-drift {
    0% { transform: rotate(0deg) scale(1); }
    100% { transform: rotate(360deg) scale(1.1); }
}

#stardust-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    pointer-events: none;
    z-index: 1;
}

.letter-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 40px 20px;
    z-index: 2;
    position: relative;
    overflow-y: auto;
}

.constellation-card {
    background: linear-gradient(135deg, rgba(26, 26, 46, 0.9), rgba(22, 33, 62, 0.8));
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 40px;
    max-width: 700px;
    width: 100%;
    box-shadow: 0 0 50px rgba(255, 255, 255, 0.1),
                inset 0 0 30px rgba(255, 255, 255, 0.05);
    animation: constellation-glow 3s ease-in-out infinite alternate,
               card-entrance 1s ease-out;
    position: relative;
}

@keyframes constellation-glow {
    0% { box-shadow: 0 0 50px rgba(255, 255, 255, 0.1), inset 0 0 30px rgba(255, 255, 255, 0.05); }
    100% { box-shadow: 0 0 70px rgba(255, 255, 255, 0.2), inset 0 0 40px rgba(255, 255, 255, 0.1); }
}

@keyframes card-entrance {
    0% { opacity: 0; transform: translateY(50px) scale(0.9); }
    100% { opacity: 1; transform: translateY(0) scale(1); }
}

.constellation-card::before {
    content: '';
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    background: linear-gradient(45deg, #ffeb3b, #ff9800, #e91e63, #9c27b0, #3f51b5, #00bcd4);
    border-radius: 22px;
    z-index: -1;
    animation: border-glow 4s linear infinite;
}

@keyframes border-glow {
    0% { background-position: 0% 50%; }
    100% { background-position: 100% 50%; }
}

.letter-content h2 {
    font-size: 2rem;
    color: #ffeb3b;
    margin-bottom: 25px;
    text-align: center;
    text-shadow: 0 0 15px rgba(255, 235, 59, 0.5);
}

.letter-content p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 20px;
    color: #fff;
    text-align: justify;
}

.signature {
    margin-top: 30px;
    text-align: center;
}

.signature p {
    margin-bottom: 10px;
}

.author {
    font-style: italic;
    color: #ffeb3b;
    text-shadow: 0 0 10px rgba(255, 235, 59, 0.3);
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        overflow-x: hidden;
    }
    
    .landing-text h1 {
        font-size: 1.5rem;
        padding: 0 20px;
    }
    
    .click-instruction {
        font-size: 1.1rem;
        padding: 0 20px;
    }
    
    .saturn-planet {
        width: 150px;
        height: 150px;
    }
    
    .planet-body {
        width: 90px;
        height: 90px;
    }
    
    .ring-1 { width: 130px; height: 130px; }
    .ring-2 { width: 160px; height: 160px; }
    .ring-3 { width: 190px; height: 190px; }
    
    .planets-container {
        gap: 30px;
        padding: 15px;
        justify-content: center;
        flex-direction: column;
        align-items: center;
        height: auto;
        padding-top: 60px;
        padding-bottom: 120px;
    }
    
    .planet-image {
        width: 80px;
        height: 80px;
    }
    
    .planet-name {
        font-size: 1rem;
    }
    
    .constellation-card {
        padding: 25px 20px;
        margin: 15px;
        max-width: 90%;
    }
    
    .letter-content h2 {
        font-size: 1.5rem;
    }
    
    .letter-content p {
        font-size: 1rem;
        line-height: 1.6;
        text-align: left;
    }
    
    .modal-content {
        padding: 20px;
        margin: 20px;
        max-width: 85%;
    }
    
    .modal-header h3 {
        font-size: 1.3rem;
    }
    
    .modal-body p {
        font-size: 1rem;
        line-height: 1.5;
    }
}

@media (max-width: 480px) {
    .landing-text h1 {
        font-size: 1.2rem;
        padding: 0 15px;
    }
    
    .click-instruction {
        font-size: 1rem;
        padding: 0 15px;
    }
    
    .saturn-planet {
        width: 120px;
        height: 120px;
    }
    
    .planet-body {
        width: 70px;
        height: 70px;
    }
    
    .ring-1 { width: 110px; height: 110px; }
    .ring-2 { width: 140px; height: 140px; }
    .ring-3 { width: 170px; height: 170px; }
    
    .planets-container {
        flex-direction: column;
        height: auto;
        padding: 40px 20px 140px 20px;
        gap: 25px;
    }
    
    .planet-item {
        margin-bottom: 25px;
        width: 100%;
        max-width: 200px;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    
    .planet-image {
        width: 70px;
        height: 70px;
    }
    
    .planet-name {
        font-size: 0.9rem;
        margin-top: 10px;
    }
    
    .progress-indicator {
        position: fixed;
        bottom: 20px;
        left: 50%;
        transform: translateX(-50%);
        width: 90%;
        text-align: center;
    }
    
    #progress-text {
        font-size: 0.8rem;
        margin-bottom: 10px;
    }
    
    .progress-dots {
        gap: 8px;
    }
    
    .dot {
        width: 8px;
        height: 8px;
    }
    
    .constellation-card {
        padding: 20px 15px;
        margin: 10px;
        max-width: 95%;
    }
    
    .letter-content h2 {
        font-size: 1.3rem;
        margin-bottom: 20px;
    }
    
    .letter-content p {
        font-size: 0.9rem;
        line-height: 1.5;
        margin-bottom: 15px;
        text-align: left;
    }
    
    .signature {
        margin-top: 25px;
    }
    
    .modal-content {
        padding: 15px;
        margin: 15px;
        max-width: 90%;
    }
    
    .modal-header h3 {
        font-size: 1.2rem;
    }
    
    .modal-body p {
        font-size: 0.9rem;
        line-height: 1.4;
    }
}

/* Touch-friendly improvements */
@media (max-width: 768px) {
    .planet-item {
        min-height: 44px;
        min-width: 44px;
        padding: 10px;
        -webkit-tap-highlight-color: transparent;
        -webkit-touch-callout: none;
        -webkit-user-select: none;
        user-select: none;
    }
    
    .saturn-planet {
        padding: 10px;
    }
    
    .modal-close {
        min-height: 44px;
        min-width: 44px;
        font-size: 20px;
        -webkit-tap-highlight-color: transparent;
    }
}

/* Portrait orientation on mobile and tablet - force vertical layout */
@media (max-width: 768px) and (orientation: portrait) {
    .planets-container {
        flex-direction: column !important;
        align-items: center !important;
        justify-content: flex-start !important;
        height: auto !important;
        padding-top: 60px !important;
        padding-bottom: 120px !important;
    }
    
    .planet-item {
        width: 100%;
        max-width: 200px;
        margin-bottom: 20px;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
}

/* Landscape orientation on mobile */
@media (max-height: 600px) and (orientation: landscape) {
    .landing-content {
        flex-direction: row;
        gap: 40px;
    }
    
    .saturn-container {
        margin-bottom: 0;
    }
    
    .planets-container {
        height: auto;
        padding: 20px;
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .progress-indicator {
        bottom: 10px;
    }
}