/* =========================================================
   genpatsu.io — evolved-minimal, split-screen, monochrome
   Palette:
     #0a0a0a  void black   (right panel bg)
     #171717  deep charcoal(left panel bg)
     #262626  graphite     (card surfaces, code bg)
     #525252  steel        (borders, dividers)
     #737373  concrete     (mono data)
     #a3a3a3  ash          (left body)
     #d4d4d4  bone         (right body)
     #f5f5f5  paper white  (headings)
     #facc15  amber accent (pulse / particles)
   ========================================================= */

*,
*::before,
*::after {
    box-sizing: border-box;
}

:root {
    --void: #0a0a0a;
    --charcoal: #171717;
    --graphite: #262626;
    --steel: #525252;
    --concrete: #737373;
    --ash: #a3a3a3;
    --bone: #d4d4d4;
    --paper: #f5f5f5;
    --amber: #facc15;

    --left-w: 45%;
    --right-w: 55%;

    --font-display: "Space Grotesk", "Inter", system-ui, sans-serif;
    --font-body: "Work Sans", "Inter", system-ui, sans-serif;
    --font-mono: "IBM Plex Mono", "Menlo", monospace;
}

html, body {
    margin: 0;
    padding: 0;
    background: var(--void);
    color: var(--bone);
    font-family: var(--font-body);
    font-weight: 400;
    line-height: 1.65;
    letter-spacing: 0.005em;
    font-size: clamp(1rem, 1.2vw, 1.125rem);
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    overflow-x: hidden;
    scroll-behavior: smooth;
}

body {
    min-height: 100vh;
    position: relative;
}

/* -----------------------------
   Boot overlay — fades away
   ----------------------------- */
.boot-overlay {
    position: fixed;
    inset: 0;
    background: var(--void);
    z-index: 1000;
    pointer-events: none;
    transition: opacity 1200ms ease;
}

.boot-overlay.fade {
    opacity: 0;
}

/* -----------------------------
   Top bar
   ----------------------------- */
.top-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 3rem;
    z-index: 50;
    background: linear-gradient(180deg, rgba(10,10,10,0.92) 0%, rgba(10,10,10,0.6) 60%, rgba(10,10,10,0) 100%);
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
}

.brand {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    letter-spacing: 0.06em;
    color: var(--paper);
    text-transform: lowercase;
    white-space: pre;
    min-width: 10ch;
}

.brand::after {
    content: "";
    display: inline-block;
    width: 0.55ch;
    height: 1em;
    margin-left: 0.2ch;
    vertical-align: -0.15em;
    background: var(--amber);
    animation: caret-pulse 1.2s ease-in-out infinite;
}

@keyframes caret-pulse {
    0%, 100% { opacity: 0.2; }
    50% { opacity: 1; }
}

.menu-toggle {
    width: 40px;
    height: 40px;
    background: transparent;
    border: 1px solid var(--steel);
    cursor: pointer;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    padding: 0;
    transition: border-color 300ms ease;
}

.menu-toggle:hover {
    border-color: var(--amber);
}

.menu-toggle span {
    display: block;
    width: 18px;
    height: 1px;
    background: var(--paper);
    transition: transform 300ms ease, opacity 300ms ease;
}

.menu-toggle.open span:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
}
.menu-toggle.open span:nth-child(2) {
    opacity: 0;
}
.menu-toggle.open span:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
}

/* -----------------------------
   Divider — pulsing amber line
   ----------------------------- */
.divider {
    position: fixed;
    top: 0;
    left: var(--left-w);
    width: 2px;
    height: 100vh;
    background: var(--amber);
    z-index: 40;
    transform-origin: center center;
    opacity: 0;
    box-shadow: 0 0 12px rgba(250, 204, 21, 0.35);
    animation: divider-pulse 4s ease-in-out infinite;
    transition: opacity 1200ms ease 400ms;
}

.divider.visible {
    opacity: 0.6;
}

@keyframes divider-pulse {
    0%, 100% { opacity: 0.3; }
    50%      { opacity: 0.8; }
}

/* -----------------------------
   Split layout
   ----------------------------- */
.split {
    display: flex;
    width: 100%;
    min-height: 100vh;
}

.panel-left {
    width: var(--left-w);
    background: var(--charcoal);
    position: sticky;
    top: 0;
    height: 100vh;
    overflow: hidden;
    padding: 120px 3rem 3rem;
    color: var(--ash);
}

.context-stack {
    position: relative;
    width: 100%;
    height: calc(100% - 120px);
    max-width: 520px;
}

.context-card {
    position: absolute;
    inset: 0;
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 400ms ease, transform 600ms ease;
    pointer-events: none;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.context-card.active {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.ctx-label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.2em;
    color: var(--concrete);
    text-transform: uppercase;
}

.ctx-title {
    font-family: var(--font-display);
    font-weight: 500;
    font-size: clamp(1.4rem, 3vw, 2.2rem);
    line-height: 1.1;
    letter-spacing: -0.02em;
    color: var(--paper);
    text-transform: lowercase;
    max-width: 18ch;
}

.ctx-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    padding-top: 0.25rem;
    border-top: 1px solid var(--steel);
    padding-top: 1rem;
}

.ctx-meta .mono {
    color: var(--concrete);
    font-size: 0.78rem;
}

.ctx-body {
    font-weight: 300;
    color: var(--ash);
    margin: 0;
    max-width: 44ch;
}

.ctx-readout {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    padding: 0.85rem 1rem;
    background: rgba(38, 38, 38, 0.5);
    border: 1px solid var(--steel);
    margin-top: auto;
    max-width: 28ch;
    position: relative;
    overflow: hidden;
}

.ctx-readout::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--amber);
    animation: divider-pulse 4s ease-in-out infinite;
}

.readout-label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.15em;
    color: var(--concrete);
    text-transform: uppercase;
}

/* Mono utility */
.mono {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    letter-spacing: 0.04em;
    color: var(--concrete);
}

/* -----------------------------
   Right narrative panel
   ----------------------------- */
.panel-right {
    width: var(--right-w);
    background: var(--void);
    position: relative;
    min-height: 100vh;
    padding-top: 64px;
}

.chapter {
    position: relative;
    min-height: 100vh;
    padding: 14vh 3rem 14vh;
    overflow: hidden;
    margin-bottom: 40vh;
    isolation: isolate;
}

.chapter:last-of-type {
    margin-bottom: 20vh;
}

/* Gradient mesh backgrounds (3 variants) */
.mesh {
    position: absolute;
    inset: -10%;
    z-index: -1;
    pointer-events: none;
    opacity: 0.9;
    filter: blur(24px);
    will-change: transform, background-position;
}

.mesh-a {
    background:
        radial-gradient(ellipse at 20% 30%, rgba(255,255,255,0.06) 0%, transparent 55%),
        radial-gradient(ellipse at 80% 60%, rgba(255,255,255,0.04) 0%, transparent 60%),
        radial-gradient(ellipse at 50% 85%, rgba(0,0,0,0.4) 0%, transparent 70%);
    background-size: 200% 200%;
    background-position: 0% 0%;
    animation: mesh-drift-a 60s ease-in-out infinite alternate;
}

.mesh-b {
    background:
        radial-gradient(ellipse at 70% 20%, rgba(255,255,255,0.05) 0%, transparent 55%),
        radial-gradient(ellipse at 30% 70%, rgba(255,255,255,0.07) 0%, transparent 60%),
        radial-gradient(circle at 50% 50%, rgba(0,0,0,0.35) 0%, transparent 75%);
    background-size: 220% 220%;
    background-position: 100% 0%;
    animation: mesh-drift-b 75s ease-in-out infinite alternate;
}

.mesh-c {
    background:
        radial-gradient(ellipse at 40% 50%, rgba(255,255,255,0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 85% 80%, rgba(255,255,255,0.03) 0%, transparent 60%),
        conic-gradient(from 210deg at 30% 40%, rgba(255,255,255,0.04), rgba(0,0,0,0.2), rgba(255,255,255,0.02));
    background-size: 200% 200%;
    background-position: 50% 50%;
    animation: mesh-drift-c 90s ease-in-out infinite alternate;
}

@keyframes mesh-drift-a {
    0%   { background-position: 0% 0%;   transform: scale(1) rotate(0deg); }
    100% { background-position: 60% 40%; transform: scale(1.05) rotate(1.5deg); }
}
@keyframes mesh-drift-b {
    0%   { background-position: 100% 0%; transform: scale(1.02) rotate(-1deg); }
    100% { background-position: 40% 70%; transform: scale(1.06) rotate(1deg); }
}
@keyframes mesh-drift-c {
    0%   { background-position: 50% 50%; transform: scale(1) rotate(0deg); }
    100% { background-position: 30% 80%; transform: scale(1.04) rotate(-1.5deg); }
}

/* Contour SVG lines */
.contour {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    opacity: 0.4;
}

.contour-path {
    fill: none;
    stroke: #262626;
    stroke-width: 1;
    stroke-dasharray: 1400;
    stroke-dashoffset: 1400;
    transition: stroke-dashoffset 1800ms ease;
}

.chapter.revealed .contour-path {
    stroke-dashoffset: 0;
}

/* Chapter inner content */
.chapter-inner {
    position: relative;
    max-width: 520px;
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 800ms ease, transform 1000ms ease;
}

.chapter.revealed .chapter-inner {
    opacity: 1;
    transform: translateY(0);
}

.chapter-kicker {
    color: var(--concrete);
    font-size: 0.75rem;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    padding-left: 1rem;
    border-left: 2px solid var(--amber);
    animation: divider-pulse 4s ease-in-out infinite;
}

.chapter-title {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: clamp(2.2rem, 5vw, 4rem);
    line-height: 1.1;
    letter-spacing: -0.02em;
    color: var(--paper);
    text-transform: lowercase;
    margin: 0;
    padding-left: 1rem;
    border-left: 2px solid var(--amber);
    animation: divider-pulse 4s ease-in-out infinite;
}

.chapter-title .word {
    display: inline-block;
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 600ms ease, transform 800ms ease;
    margin-right: 0.3em;
}

.chapter.revealed .chapter-title .word {
    opacity: 1;
    transform: translateY(0);
}

.chapter.revealed .chapter-title .word:nth-child(1) { transition-delay: 0ms; }
.chapter.revealed .chapter-title .word:nth-child(2) { transition-delay: 300ms; }
.chapter.revealed .chapter-title .word:nth-child(3) { transition-delay: 600ms; }

.chapter-body {
    color: var(--bone);
    font-weight: 400;
    margin: 0;
    max-width: 520px;
}

.chapter-body code {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    letter-spacing: 0.04em;
    color: var(--paper);
    background: var(--graphite);
    padding: 2px 6px;
    border-radius: 2px;
}

/* Data bubble marginalia */
.data-bubble {
    margin-top: 1rem;
    width: 96px;
    height: 96px;
    border: 1px solid var(--steel);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(38, 38, 38, 0.3);
    position: relative;
    transition: border-color 400ms ease, transform 400ms ease;
}

.data-bubble::after {
    content: "";
    position: absolute;
    inset: -6px;
    border: 1px solid var(--amber);
    border-radius: 50%;
    opacity: 0;
    transform: scale(1);
    transition: opacity 600ms ease, transform 600ms ease;
}

.data-bubble:hover {
    border-color: var(--amber);
}

.data-bubble:hover::after {
    opacity: 0;
    transform: scale(1.5);
    animation: ring-pulse 600ms ease forwards;
}

@keyframes ring-pulse {
    0%   { opacity: 1; transform: scale(1); }
    100% { opacity: 0; transform: scale(1.5); }
}

.data-bubble code {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.08em;
    color: var(--paper);
}

/* -----------------------------
   Right-panel footer
   ----------------------------- */
.right-footer {
    padding: 4rem 3rem 5rem;
    position: relative;
}

.footer-line {
    height: 1px;
    background: var(--steel);
    margin-bottom: 1.5rem;
    position: relative;
    overflow: hidden;
}

.footer-line::after {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    width: 80px;
    height: 1px;
    background: var(--amber);
    animation: footer-line-pulse 4s ease-in-out infinite;
}

@keyframes footer-line-pulse {
    0%, 100% { transform: translateX(0); opacity: 0.3; }
    50%      { transform: translateX(120px); opacity: 0.8; }
}

.footer-meta {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
    color: var(--concrete);
    font-size: 0.78rem;
    letter-spacing: 0.1em;
    text-transform: lowercase;
}

/* -----------------------------
   Overlay menu
   ----------------------------- */
.overlay-menu {
    position: fixed;
    inset: 0;
    background: rgba(10, 10, 10, 0.96);
    z-index: 45;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity 500ms ease;
}

.overlay-menu.open {
    opacity: 1;
    pointer-events: auto;
}

.overlay-menu ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    text-align: center;
}

.overlay-menu a {
    font-family: var(--font-display);
    font-weight: 500;
    font-size: clamp(1.4rem, 3vw, 2.2rem);
    letter-spacing: -0.02em;
    color: var(--ash);
    text-decoration: none;
    text-transform: lowercase;
    transition: color 300ms ease;
    position: relative;
    padding-left: 1rem;
}

.overlay-menu a::before {
    content: "";
    position: absolute;
    left: -1rem;
    top: 50%;
    transform: translateY(-50%) scaleX(0);
    width: 16px;
    height: 2px;
    background: var(--amber);
    transition: transform 300ms ease;
    transform-origin: left;
}

.overlay-menu a:hover {
    color: var(--paper);
}

.overlay-menu a:hover::before {
    transform: translateY(-50%) scaleX(1);
}

/* -----------------------------
   Containment circles
   ----------------------------- */
.containment-field {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    overflow: hidden;
}

.containment-circle {
    position: absolute;
    width: var(--size, 260px);
    height: var(--size, 260px);
    top: var(--top, 20%);
    left: var(--left, 60%);
    border: 1px solid var(--steel);
    border-radius: 50%;
    opacity: 0.15;
    mix-blend-mode: overlay;
    animation: drift var(--dur, 16s) linear infinite;
}

@keyframes drift {
    0%   { transform: translate(0, 0); }
    25%  { transform: translate(40px, -30px); }
    50%  { transform: translate(20px, 40px); }
    75%  { transform: translate(-30px, 20px); }
    100% { transform: translate(0, 0); }
}

/* -----------------------------
   Particle dots (decay events)
   ----------------------------- */
.particle-field {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 3;
    overflow: hidden;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    border-radius: 50%;
    background: var(--amber);
    box-shadow: 0 0 6px rgba(250, 204, 21, 0.8);
    opacity: 0;
    transform: scale(0.6);
    animation: particle-life 2500ms ease forwards;
}

@keyframes particle-life {
    0%   { opacity: 0; transform: scale(0.4); }
    12%  { opacity: 1; transform: scale(1); }
    70%  { opacity: 1; transform: scale(1); }
    100% { opacity: 0; transform: scale(1.4); }
}

/* -----------------------------
   Scroll-reveal helpers (brand typed in)
   ----------------------------- */
.brand.typed-step::after {
    animation-duration: 0.8s;
}

/* -----------------------------
   Scrollbar tuning (subtle)
   ----------------------------- */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: var(--void);
}
::-webkit-scrollbar-thumb {
    background: var(--graphite);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--steel);
}

/* -----------------------------
   Selection
   ----------------------------- */
::selection {
    background: var(--amber);
    color: var(--void);
}

/* -----------------------------
   Mobile adaptation — collapse split
   ----------------------------- */
@media (max-width: 768px) {
    :root {
        --left-w: 100%;
        --right-w: 100%;
    }

    .divider {
        display: none;
    }

    .split {
        flex-direction: column;
    }

    .panel-left {
        position: relative;
        width: 100%;
        height: auto;
        padding: 96px 1.5rem 3rem;
        border-bottom: 1px solid var(--steel);
    }

    .context-stack {
        position: relative;
        height: auto;
        min-height: 280px;
    }

    .panel-right {
        width: 100%;
        padding-top: 0;
    }

    .chapter {
        padding: 10vh 1.5rem;
        margin-bottom: 20vh;
    }

    .chapter-inner {
        max-width: 100%;
    }

    .top-bar {
        padding: 0 1.25rem;
    }

    /* Horizontal pulse-bar divider between sections on mobile */
    .chapter::after {
        content: "";
        position: absolute;
        left: 1.5rem;
        right: 1.5rem;
        bottom: -10vh;
        height: 2px;
        background: var(--amber);
        opacity: 0.4;
        animation: divider-pulse 4s ease-in-out infinite;
    }
}