/* CSS Variables for theming */
:root {
    --bg-color: #faf9f6;
    --text-color: #2c3e50;
    --text-secondary: #5a6c7d;
    --line-color: rgba(100, 149, 237, 0.25);
    --line-color-strong: rgba(100, 149, 237, 0.4);
    --accent-color: #74a1b1;
    --accent-hover: #3a7bc8;
    --nav-bg: rgba(250, 249, 246, 0.85);
    --transition-speed: 0.4s;
}

[data-theme="dark"] {
    --bg-color: #0a0a0a;
    --text-color: #f0f0f0;
    --text-secondary: #b0b0b0;
    --line-color: rgba(255, 255, 255, 0.08);
    --line-color-strong: rgba(255, 255, 255, 0.15);
    --accent-color: #5780a3;
    --accent-hover: #8fc4f5;
    --nav-bg: rgba(10, 10, 10, 0.85);
}

/* Reset and base styles */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Caveat', 'Patrick Hand', cursive;
    background-color: var(--bg-color);
    color: var(--text-color);
    min-height: 100vh;
    transition: background-color var(--transition-speed) ease,
                color var(--transition-speed) ease;
    overflow-x: hidden;
}

/* Hand-drawn graph paper background */
.graph-paper {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    transition: opacity var(--transition-speed) ease;
}

.graph-paper::before,
.graph-paper::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/* Small grid lines - dashed for subtle effect */
.graph-paper::before {
    background-image:
        /* Vertical dashed lines */
        repeating-linear-gradient(
            90deg,
            transparent,
            transparent 24px,
            var(--line-color) 24px,
            var(--line-color) 25px
        ),
        /* Horizontal dashed lines */
        repeating-linear-gradient(
            0deg,
            transparent,
            transparent 24px,
            var(--line-color) 24px,
            var(--line-color) 25px
        ),
        /* Dashing mask - vertical */
        repeating-linear-gradient(
            0deg,
            var(--bg-color),
            var(--bg-color) 4px,
            transparent 4px,
            transparent 8px
        );
    transform: rotate(-0.2deg);
    opacity: 0.5;
    transition: opacity var(--transition-speed) ease;
}

/* Larger grid lines for major divisions */
.graph-paper::after {
    background-image:
        repeating-linear-gradient(
            90deg,
            transparent,
            transparent 99px,
            var(--line-color-strong) 99px,
            var(--line-color-strong) 100px
        ),
        repeating-linear-gradient(
            0deg,
            transparent,
            transparent 99px,
            var(--line-color-strong) 99px,
            var(--line-color-strong) 100px
        ),
        /* Dashing mask */
        repeating-linear-gradient(
            0deg,
            var(--bg-color),
            var(--bg-color) 6px,
            transparent 6px,
            transparent 12px
        );
    transform: rotate(0.1deg);
    opacity: 0.4;
    transition: opacity var(--transition-speed) ease;
}

/* Add subtle paper texture overlay */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%' height='100%' filter='url(%23noise)'/%3E%3C/svg%3E");
    opacity: 0.02;
}

/* Header and Navigation */
header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 1.5rem 2rem;
    background: var(--nav-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: background var(--transition-speed) ease;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-signature {
    display: flex;
    align-items: baseline;
    gap: 0.4rem;
}

.by-text {
    font-family: 'Patrick Hand', cursive;
    font-size: 1.1rem;
    color: var(--text-secondary);
    letter-spacing: 0.05em;
}

.signature-name {
    font-family: 'Caveat', cursive;
    font-size: 2rem;
    font-weight: 600;
    color: var(--text-color);
    letter-spacing: 0.02em;
}

/* Theme toggle button */
.theme-toggle {
    background: none;
    border: 2px solid var(--text-color);
    border-radius: 50%;
    width: 44px;
    height: 44px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    transition: all 0.3s ease;
    position: relative;
}

.theme-toggle:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
    transform: rotate(15deg);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    position: absolute;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.sun-icon {
    opacity: 0;
    transform: rotate(-90deg);
}

.moon-icon {
    opacity: 1;
    transform: rotate(0deg);
}

[data-theme="dark"] .sun-icon {
    opacity: 1;
    transform: rotate(0deg);
}

[data-theme="dark"] .moon-icon {
    opacity: 0;
    transform: rotate(90deg);
}

/* Main content */
main {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem;
}

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    max-width: 800px;
    padding-top: 4rem;
}

.content {
    text-align: center;
}

/* Typography with fade-in animation */
.greeting {
    font-family: 'Caveat', cursive;
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    font-weight: 700;
    margin-bottom: 0.25rem;
    line-height: 1.2;
    transition: color var(--transition-speed) ease;
}

.greeting-text {
    display: inline;
    font-family: 'Caveat', 'Zen Kurenaido', 'ZCOOL XiaoWei', 'Nanum Pen Script', cursive;
}

.greeting-text::after {
    content: '|';
    display: inline-block;
    margin-left: 2px;
    animation: blink 0.8s infinite;
    font-weight: 400;
    opacity: 0.7;
}

@keyframes blink {
    0%, 50% { opacity: 0.7; }
    51%, 100% { opacity: 0; }
}

.tagline {
    font-family: 'Caveat', cursive;
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 500;
    color: var(--accent-color);
    margin-bottom: 2rem;
    transition: color var(--transition-speed) ease;
}

.description {
    font-family: 'Patrick Hand', cursive;
    font-size: clamp(1.2rem, 3vw, 1.6rem);
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    max-width: 650px;
    margin-left: auto;
    margin-right: auto;
    transition: color var(--transition-speed) ease;
    text-wrap: pretty;
}

.cta {
    font-family: 'Patrick Hand', cursive;
    font-size: clamp(1.3rem, 3vw, 1.7rem);
    line-height: 1.6;
    transition: color var(--transition-speed) ease;
}

.cta a {
    color: var(--accent-color);
    text-decoration: none;
    font-weight: 600;
    position: relative;
    transition: color 0.3s ease;
}

.cta a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--accent-color);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.3s ease;
}

.cta a:hover {
    color: var(--accent-hover);
}

.cta a:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

/* Fade-in animation */
.fade-in {
    animation: fadeInUp 1s ease forwards;
}

.fade-in .greeting {
    opacity: 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.2s;
}

.fade-in .tagline {
    opacity: 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.4s;
}

.fade-in .description {
    opacity: 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.6s;
}

.fade-in .cta {
    opacity: 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.8s;
}

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

/* Hand-drawn decorative elements */
.hero::before {
    content: '';
    position: absolute;
    width: 60px;
    height: 60px;
    border: 2px solid var(--line-color-strong);
    border-radius: 50%;
    top: 20%;
    left: 10%;
    transform: rotate(15deg);
    opacity: 0.5;
}

.hero::after {
    content: '';
    position: absolute;
    width: 40px;
    height: 40px;
    border: 2px solid var(--line-color-strong);
    bottom: 20%;
    right: 15%;
    transform: rotate(-10deg);
    opacity: 0.5;
}

/* Reading Section */
.reading-section {
    width: 100%;
    padding: 6rem 0 4rem;
    margin-top: 2rem;
}

.section-title {
    font-family: 'Caveat', cursive;
    font-size: clamp(2rem, 5vw, 3rem);
    text-align: center;
    margin-bottom: 0.75rem;
    color: var(--text-color);
    transition: color var(--transition-speed) ease;
}

.section-subtitle {
    font-family: 'Patrick Hand', cursive;
    font-size: clamp(1.1rem, 2.5vw, 1.4rem);
    text-align: center;
    color: var(--text-secondary);
    font-weight: 400;
    margin-bottom: 2.5rem;
    transition: color var(--transition-speed) ease;
}

/* Carousel Container */
.carousel-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    padding: 0 1rem;
    max-width: 1000px;
    margin: 0 auto;
}

.carousel-btn {
    background: var(--bg-color);
    border: 2px solid var(--line-color-strong);
    border-radius: 50%;
    width: 44px;
    height: 44px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.carousel-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.carousel-btn:focus {
    outline: 2px dashed var(--accent-color);
    outline-offset: 4px;
}

.carousel-btn svg {
    width: 20px;
    height: 20px;
}

.papers-carousel {
    overflow: hidden;
    width: 100%;
    max-width: 750px;
}

.carousel-track {
    display: flex;
    gap: 1.5rem;
    transition: transform 0.4s ease;
    padding: 1.5rem 0;
}

.paper-card {
    flex-shrink: 0;
    width: 220px;
    text-decoration: none;
    color: var(--text-color);
    background: var(--bg-color);
    border: 2px solid var(--line-color-strong);
    border-radius: 8px;
    overflow: hidden;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
    opacity: 1;
}

.paper-card.active {
    border-color: var(--accent-color);
    box-shadow: 0 0 16px rgba(70, 130, 180, 0.2);
}

[data-theme="dark"] .paper-card.active {
    box-shadow: 0 0 16px rgba(70, 130, 180, 0.3);
}

.paper-card:hover {
    border-color: var(--accent-color);
}

.paper-image {
    width: 100%;
    height: 180px;
    overflow: hidden;
    background: var(--line-color);
}

.paper-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top;
    transition: transform 0.3s ease;
}

.paper-card:hover .paper-image img {
    transform: scale(1.03);
}

.paper-info {
    padding: 1rem;
}

.paper-info h3 {
    font-family: 'Patrick Hand', cursive;
    font-size: 1.05rem;
    line-height: 1.3;
    margin-bottom: 0.4rem;
    color: var(--text-color);
    transition: color var(--transition-speed) ease;
}

.paper-info p {
    font-family: 'Patrick Hand', cursive;
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: color var(--transition-speed) ease;
}

.paper-card:focus {
    outline: 2px dashed var(--accent-color);
    outline-offset: 4px;
}

/* Photography Section */
.photography-section {
    width: 100%;
    padding: 4rem 2rem 6rem;
    position: relative;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    position: relative;
}

.shuffle-btn {
    position: relative;
    background: var(--bg-color);
    border: 1.5px solid var(--line-color-strong);
    border-radius: 50%;
    width: 32px;
    height: 32px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: opacity 0.3s ease, border-color 0.3s ease, color 0.3s ease;
    opacity: 0.7;
    margin-left: 0.75rem;
    animation: shuffleBtnFloat 3s ease-in-out infinite;
}

@keyframes shuffleBtnFloat {
    0%, 100% {
        transform: translateX(0) translateY(0);
    }
    20% {
        transform: translateX(-8px) translateY(-6px);
    }
    40% {
        transform: translateX(5px) translateY(-10px);
    }
    60% {
        transform: translateX(-6px) translateY(4px);
    }
    80% {
        transform: translateX(8px) translateY(-3px);
    }
}

.shuffle-btn:hover {
    opacity: 1;
    border-color: var(--accent-color);
    color: var(--accent-color);
    animation-play-state: paused;
}

.shuffle-btn:active {
    transform: scale(0.9);
}

.shuffle-btn:focus {
    outline: 2px dashed var(--accent-color);
    outline-offset: 4px;
}

.shuffle-btn svg {
    width: 16px;
    height: 16px;
}

/* Photo shuffle animation */
.photo-item.shuffling {
    opacity: 0;
    transform: scale(0.8) translateY(20px);
}

.photo-gallery.is-shuffling {
    pointer-events: none;
}

.photo-gallery {
    columns: 3;
    column-gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.photo-item {
    display: block;
    break-inside: avoid;
    margin-bottom: 2.5rem;
    position: relative;
    text-decoration: none;
    cursor: pointer;
}

.photo-pin {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
    padding-left: 0.25rem;
}

.pin {
    width: 10px;
    height: 10px;
    background: #222222;
    border-radius: 50%;
    position: relative;
}

.pin::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 5px;
    background: #222222;
    border-radius: 1px;
}

[data-theme="dark"] .pin {
    background: #e0e0e0;
}

[data-theme="dark"] .pin::after {
    background: #e0e0e0;
}

.photo-location {
    font-family: 'Patrick Hand', cursive;
    font-size: 1rem;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
}

.photo-item img {
    width: 100%;
    height: auto;
    border-radius: 4px;
    display: block;
    transition: transform 0.4s ease, box-shadow 0.4s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] .photo-item img {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.photo-item:hover img {
    transform: scale(1.02);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

[data-theme="dark"] .photo-item:hover img {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
}

.photo-item::after {
    content: 'read story';
    position: absolute;
    bottom: 1rem;
    right: 1rem;
    font-family: 'Patrick Hand', cursive;
    font-size: 0.9rem;
    color: #ffffff;
    background: rgba(0, 0, 0, 0.6);
    padding: 0.35rem 0.75rem;
    border-radius: 20px;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 0.3s ease, transform 0.3s ease;
    pointer-events: none;
}

.photo-item:hover::after {
    opacity: 1;
    transform: translateY(0);
}

.photo-item:focus {
    outline: 2px dashed var(--accent-color);
    outline-offset: 4px;
}

/* Featured Section */
.featured-section {
    width: 100%;
    max-width: 700px;
    padding: 4rem 2rem;
}

.featured-links {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.featured-link {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.25rem;
    text-decoration: none;
    color: var(--text-color);
    background: var(--bg-color);
    border: 2px solid var(--line-color-strong);
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
}

.featured-link:hover {
    border-color: var(--accent-color);
    transform: translateX(8px);
    box-shadow: -4px 4px 0 var(--accent-color);
}

.link-source {
    font-family: 'Patrick Hand', cursive;
    font-size: 0.85rem;
    padding: 0.25rem 0.75rem;
    background: var(--accent-color);
    color: var(--bg-color);
    border-radius: 20px;
    white-space: nowrap;
    flex-shrink: 0;
}

.link-title {
    font-family: 'Patrick Hand', cursive;
    font-size: 1.15rem;
    flex: 1;
    line-height: 1.3;
}

.link-arrow {
    font-size: 1.5rem;
    color: var(--accent-color);
    transition: transform 0.3s ease;
    flex-shrink: 0;
}

.featured-link:hover .link-arrow {
    transform: translateX(4px);
}

.featured-link:focus {
    outline: 2px dashed var(--accent-color);
    outline-offset: 4px;
}

/* Responsive design */
@media (max-width: 768px) {
    header {
        padding: 1rem;
    }

    .by-text {
        font-size: 1rem;
    }

    .signature-name {
        font-size: 1.8rem;
    }

    .hero {
        padding-top: 3rem;
    }

    .theme-toggle {
        width: 40px;
        height: 40px;
    }

    .carousel-container {
        gap: 0.75rem;
    }

    .carousel-btn {
        width: 36px;
        height: 36px;
    }

    .carousel-btn svg {
        width: 16px;
        height: 16px;
    }

    .papers-carousel {
        max-width: 550px;
    }

    .carousel-track {
        gap: 1rem;
    }

    .paper-card {
        width: 160px;
    }

    .paper-image {
        height: 130px;
    }

    .photo-gallery {
        columns: 2;
        column-gap: 1.5rem;
    }

    .photo-item {
        margin-bottom: 2rem;
    }

    .featured-link {
        flex-wrap: wrap;
    }

    .link-title {
        order: 3;
        width: 100%;
        margin-top: 0.5rem;
    }

    .link-arrow {
        margin-left: auto;
    }
}

@media (max-width: 480px) {
    .by-text {
        font-size: 0.95rem;
    }

    .signature-name {
        font-size: 1.6rem;
    }

    main {
        padding: 1rem;
    }

    .photo-gallery {
        columns: 1;
    }

    .photography-section {
        padding: 3rem 1rem 4rem;
    }

    .shuffle-btn {
        width: 28px;
        height: 28px;
        margin-left: 0.5rem;
    }

    .shuffle-btn svg {
        width: 12px;
        height: 12px;
    }
}

/* Site Footer */
.site-footer {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: 4rem 2rem 3rem;
    text-align: center;
}

.footer-note {
    font-family: 'Caveat', cursive;
    font-size: 1.5rem;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
    opacity: 0.8;
}

/* Smooth scrolling and selection */
::selection {
    background: var(--accent-color);
    color: var(--bg-color);
}

/* Focus styles for accessibility */
.theme-toggle:focus,
.cta a:focus {
    outline: 2px dashed var(--accent-color);
    outline-offset: 4px;
}

/* Scroll reveal animation for photos */
.photo-item {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.photo-item.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* Reduce motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    .photo-item {
        opacity: 1;
        transform: none;
    }
}