/* CSS Variables */
:root {
    --bg-color: #0a0a0a;
    --text-primary: #f0f0f0;
    --text-secondary: #888888;
    --accent-color: #ccff00;
    /* Acid Green variant */
    --surface-color: #151515;

    --font-serif: 'Instrument Serif', serif;
    --font-sans: 'Inter', sans-serif;

    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 8rem;

    --nav-h: 72px;

    color-scheme: dark;
}

/* Accessibility Utility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

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

html {
    scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
    transition: opacity 0.2s ease;
}

a:hover {
    opacity: 0.8;
}

a:focus-visible,
.btn-primary:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 4px;
    border-radius: 8px;
}

.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--accent-color);
    color: black;
    padding: 8px;
    z-index: 200;
    transition: top 0.2s;
}

.skip-link:focus {
    top: 0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

/* Typography */
h1,
h2,
h3 {
    font-family: var(--font-serif);
    font-weight: 400;
}

section {
    scroll-margin-top: calc(var(--nav-h) + 16px);
}

.section-header {
    font-size: 3rem;
    margin-bottom: var(--space-lg);
    border-bottom: 1px solid #333;
    padding-bottom: var(--space-sm);
}

.text-center {
    text-align: center;
}

/* Nav */
.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(10px);
    height: var(--nav-h);
}

.logo {
    font-weight: 900;
    letter-spacing: -0.05em;
    font-size: 1.5rem;
}

.nav-links {
    display: flex;
    gap: var(--space-md);
    align-items: center;
}

.btn-primary {
    background: var(--text-primary);
    color: var(--bg-color);
    padding: 0.5rem 1.5rem;
    border-radius: 999px;
    font-weight: 600;
}

.btn-primary:hover {
    background: var(--accent-color);
}

/* Hero */
.hero-section {
    min-height: 90vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding-top: var(--space-xl);
}

.hero-title {
    font-size: clamp(3rem, 8vw, 6rem);
    line-height: 1.1;
    margin-bottom: var(--space-md);
}

.hero-title i {
    font-style: italic;
    color: var(--text-secondary);
}

/* Prevent layout shift during typewriter animation */
.dynamic-wrapper {
    display: block;
    min-height: 1.2em;
    /* Reserve space for the tallest text */
}

.dynamic-text {
    display: inline-block;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
}

.sub-detail {
    display: inline-block;
    margin-top: 0.5rem;
    color: #777;
    letter-spacing: 0.02em;
    font-size: 0.9rem;
}

.hero-img {
    margin-top: var(--space-lg);
    border-radius: 0 0 2rem 2rem;
    width: 100%;
    max-width: 800px;
    /* Constraint */
    height: auto;
    max-height: 80vh;
    object-fit: cover;
    opacity: 0.9;
    transition: filter 0.5s ease;
}

/* Bridge */
.bridge-section {
    padding: var(--space-xl) 0;
    background: var(--surface-color);
    text-align: center;
}

.bridge-text {
    font-family: var(--font-serif);
    font-size: clamp(1.5rem, 4vw, 2.5rem);
    font-style: italic;
    color: var(--text-secondary);
}

/* Bento Grid */
.bento-section {
    padding: var(--space-xl) 0;
}

.bento-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 2rem 0;
}

/* Desktop Grid */
@media (min-width: 768px) {
    .bento-grid {
        grid-template-columns: repeat(3, 1fr);
        grid-template-rows: repeat(2, 300px);
    }

    .card-large {
        grid-column: span 2;
    }

    .card-tall {
        grid-row: span 2;
    }
}

.bento-card {
    background: var(--surface-color);
    border: 1px solid #333;
    padding: 2rem;
    border-radius: 1.5rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.bento-card:hover {
    transform: translateY(-5px);
    border-color: var(--text-primary);
}

.card-tag {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-secondary);
    border: 1px solid #333;
    width: fit-content;
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
}

.bento-card h3 {
    font-family: var(--font-sans);
    font-weight: 700;
    font-size: 1.5rem;
    margin-top: 1rem;
}

.card-detail {
    color: var(--text-secondary);
    margin-top: 0.75rem;
    font-size: 0.95rem;
}

.card-tall {
    background-size: cover;
    background-position: center;
    position: relative;
    overflow: hidden;
}

.card-overlay {
    background: linear-gradient(to top, rgba(0, 0, 0, 0.9), transparent);
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
}

.card-accent {
    background: var(--text-primary);
    color: var(--bg-color);
}

.card-accent .card-tag {
    color: #444;
    border-color: #999;
}

/* Profile */
.profile-section {
    padding: var(--space-xl) 0;
    background: var(--bg-color);
}

.profile-bio {
    max-width: 600px;
    margin: var(--space-md) auto;
    font-size: 1.2rem;
    color: var(--text-secondary);
}

/* Masonry / Vibe */
.gallery-section {
    padding-bottom: var(--space-xl);
}

.masonry-grid {
    column-count: 1;
    column-gap: var(--space-sm);
}

@media (min-width: 600px) {
    .masonry-grid {
        column-count: 2;
    }
}

@media (min-width: 900px) {
    .masonry-grid {
        column-count: 3;
    }
}

.masonry-item {
    break-inside: avoid;
    margin-bottom: var(--space-sm);
    position: relative;
    cursor: pointer;
}

.masonry-item:focus {
    outline: 2px solid var(--accent-color);
    border-radius: 8px;
}

.masonry-item img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    display: block;
    transition: filter 0.3s ease;
    object-fit: cover;
    aspect-ratio: 4 / 5;
    /* Consistent portrait ratio */
}

.masonry-item figcaption {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 0.5rem;
    font-size: 0.8rem;
    opacity: 0;
    transition: opacity 0.3s ease;
    border-radius: 0 0 8px 8px;
    pointer-events: none;
}

.masonry-item:hover figcaption,
.masonry-item:focus-within figcaption {
    opacity: 1;
}

/* Footer */
.footer-section {
    padding: var(--space-xl) 0;
    text-align: center;
    border-top: 1px solid #222;
}

.footer-cta {
    font-size: 3rem;
    margin-bottom: var(--space-sm);
}

.social-links {
    display: flex;
    justify-content: center;
    gap: var(--space-md);
    margin-top: var(--space-md);
}

.copyright {
    margin-top: var(--space-lg);
    color: #444;
    font-size: 0.8rem;
}

/* Responsive */
@media (max-width: 768px) {
    .masonry-grid {
        column-count: 1;
    }

    .footer-cta {
        font-size: 2rem;
    }

    .hero-img {
        border-radius: 1rem;
    }

    /* Mobile Nav Logic: Hide links but keep updated CTA */
    .nav-links a:not(.btn-primary) {
        display: none;
    }

    .nav-links {
        gap: 0;
    }

    /* Mobile Menu would go here in V3 */
}

/* Pages (Scholar's Study) */
.page-container {
    padding-top: calc(var(--nav-h) + var(--space-xl));
    min-height: 80vh;
}

.notebook-header {
    margin-bottom: var(--space-lg);
}

.notebook-title {
    font-size: clamp(3rem, 6vw, 5rem);
    font-family: var(--font-serif);
    line-height: 1.1;
    color: var(--text-primary);
}

.notebook-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-top: 1rem;
    font-family: var(--font-serif);
    font-style: italic;
}

.essay-list {
    display: flex;
    flex-direction: column;
    gap: 0;
    border-top: 1px solid #333;
}

.essay-item {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 1.5rem 0;
    border-bottom: 1px solid #333;
    transition: padding-left 0.3s ease;
}

.essay-item:hover {
    padding-left: 1rem;
    border-color: var(--text-primary);
}

.essay-date {
    font-family: var(--font-sans);
    font-size: 0.9rem;
    color: #666;
    min-width: 120px;
}

.essay-title {
    font-size: 1.5rem;
    font-family: var(--font-serif);
    font-weight: 400;
}

/* Essay Featured Article */
.essay-featured {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
    background: var(--surface-color);
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: var(--space-md);
    border: 1px solid #333;
}

.essay-featured:hover {
    padding-left: 2rem;
    border-color: var(--accent-color);
}

.essay-featured .essay-title {
    font-size: 2rem;
    margin: 0;
}

.essay-excerpt {
    color: var(--text-secondary);
    font-size: 1.1rem;
    line-height: 1.7;
}

.essay-coming-soon {
    text-align: center;
    padding: var(--space-lg) 0;
    color: var(--text-secondary);
}

.essay-coming-soon p {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.essay-hint {
    font-style: italic;
    font-size: 0.95rem !important;
    color: #555;
}

/* Now Page */
.now-list {
    list-style: none;
    margin-top: var(--space-md);
}

.now-item {
    margin-bottom: var(--space-md);
    padding-left: 1.5rem;
    border-left: 2px solid #333;
}

.now-item strong {
    color: var(--text-primary);
    display: block;
    margin-bottom: 0.25rem;
    font-family: var(--font-serif);
    font-size: 1.2rem;
}

.now-item p {
    color: var(--text-secondary);
}

/* Library Page */
.book-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--space-md);
    margin-top: var(--space-md);
}

.book-item {
    background: var(--surface-color);
    padding: 1.5rem;
    border-radius: 8px;
    border: 1px solid #333;
    transition: transform 0.2s ease;
}

.book-item:hover {
    transform: translateY(-2px);
    border-color: var(--text-primary);
}

.book-title {
    font-weight: 600;
    margin-bottom: 0.25rem;
    display: block;
    font-family: var(--font-serif);
    font-size: 1.2rem;
}

.book-author {
    color: var(--text-secondary);
    font-size: 0.9rem;
}