/* ============================================================
   ronpa.day — Light-academia for the art of refutation
   Palette: warm parchment, neon-electric violet strikes
   Layout:  immersive-scroll master class
   ============================================================ */

:root {
    --parchment-warm: #F5ECD7;
    --scholar-brown: #4A3828;
    --refutation-violet: #8B5CF6;
    --strike-red: #EF4444;
    --blob-lavender: #DDD6FE;
    --page-white: #FEFCF8;
    --ink-dark: #1C1917;

    --font-headline: 'Nunito', system-ui, sans-serif;
    --font-body: 'Source Serif 4', Georgia, serif;
    --font-mono: 'JetBrains Mono', ui-monospace, monospace;

    --scroll-pct: 0;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: clamp(16px, 1.5vw, 18px);
    line-height: 1.85;
    color: var(--scholar-brown);
    background: var(--parchment-warm);
    overflow-x: hidden;
}

/* ============================================================
   Scroll progress bar — fixed neon-electric strip
   ============================================================ */
#progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 2px;
    width: calc(var(--scroll-pct) * 100%);
    background: var(--refutation-violet);
    box-shadow: 0 0 8px rgba(139, 92, 246, 0.55);
    z-index: 100;
    transition: width 80ms linear;
}

/* ============================================================
   Section frame — immersive scroll
   ============================================================ */
.section {
    position: relative;
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 60px clamp(24px, 6vw, 96px);
    overflow: hidden;
}

.section-parchment {
    background: var(--parchment-warm);
    color: var(--scholar-brown);
}

.section-white {
    background: var(--page-white);
    color: var(--ink-dark);
}

/* Paper-aged texture: layered warm gradients + SVG noise */
.paper-texture {
    position: absolute;
    inset: 0;
    pointer-events: none;
    background:
        radial-gradient(ellipse at 20% 10%, rgba(196, 162, 100, 0.18) 0%, transparent 55%),
        radial-gradient(ellipse at 80% 80%, rgba(180, 140, 80, 0.14) 0%, transparent 60%),
        linear-gradient(135deg, rgba(245, 226, 184, 0.35) 0%, transparent 70%);
    z-index: 0;
}

.paper-texture::after {
    content: '';
    position: absolute;
    inset: 0;
    filter: url(#paper-noise);
    opacity: 0.6;
    mix-blend-mode: multiply;
}

/* ============================================================
   Section 1 — The Challenge (hero)
   ============================================================ */
#challenge {
    min-height: 100vh;
    text-align: center;
}

.hero-stack {
    position: relative;
    z-index: 2;
    max-width: 800px;
    opacity: 0;
    transform: scale(0.98);
    transition: opacity 600ms ease-out 200ms, transform 600ms ease-out 200ms;
}

.hero-stack.is-ready {
    opacity: 1;
    transform: scale(1);
}

.kanji {
    font-family: var(--font-headline);
    font-size: clamp(64px, 12vw, 160px);
    font-weight: 800;
    color: var(--scholar-brown);
    opacity: 0.12;
    letter-spacing: 0.05em;
    line-height: 1;
    margin-bottom: -0.2em;
}

#wordmark {
    font-family: var(--font-headline);
    font-weight: 800;
    font-size: clamp(40px, 7vw, 96px);
    color: var(--scholar-brown);
    letter-spacing: -0.02em;
    line-height: 1.1;
    position: relative;
    display: inline-block;
}

.wordmark-text {
    position: relative;
    display: inline-block;
}

.wordmark-text::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 0;
    height: 4px;
    background: var(--refutation-violet);
    box-shadow: 0 0 10px rgba(139, 92, 246, 0.6);
    transition: width 400ms ease-out 600ms;
}

.hero-stack.is-ready .wordmark-text::after {
    width: 100%;
}

.hero-subtitle {
    margin-top: 32px;
    font-family: var(--font-body);
    font-style: italic;
    font-size: clamp(18px, 1.8vw, 22px);
    font-weight: 400;
    color: var(--scholar-brown);
    opacity: 0.85;
}

.annotation {
    display: inline-block;
    margin-top: 28px;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--scholar-brown);
    opacity: 0.55;
    letter-spacing: 0.02em;
}

.annotation.block {
    display: block;
    margin-top: 32px;
    padding: 12px 16px;
    background: rgba(139, 92, 246, 0.06);
    border-left: 2px solid var(--refutation-violet);
    width: fit-content;
}

.scroll-indicator {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--scholar-brown);
    opacity: 0;
    transition: opacity 600ms ease-out 1100ms;
}

.hero-stack.is-ready ~ .scroll-indicator {
    opacity: 0.6;
}

.scroll-arrow {
    font-size: 20px;
    color: var(--refutation-violet);
    animation: drift 2.4s ease-in-out infinite;
}

@keyframes drift {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(8px); }
}

/* ============================================================
   Organic blobs — argument shapes
   ============================================================ */
.blob {
    position: absolute;
    fill: var(--blob-lavender);
    z-index: 1;
    opacity: 0;
    transition: opacity 800ms ease-out, transform 800ms ease-out;
}

.blob-hero {
    top: 50%;
    left: 50%;
    width: clamp(280px, 45vw, 520px);
    height: auto;
    transform: translate(-50%, -50%) scale(0.9);
    opacity: 0;
}

.hero-stack.is-ready ~ .blob-hero,
.is-visible .blob-hero {
    opacity: 0.55;
    transform: translate(-50%, -50%) scale(1);
}

.blob-side {
    width: clamp(180px, 22vw, 320px);
    height: auto;
    top: 50%;
    left: -80px;
    transform: translateY(-50%) translateX(-40px);
}

.blob-side.blob-right {
    left: auto;
    right: -80px;
    transform: translateY(-50%) translateX(40px);
}

.is-visible .blob-side {
    opacity: 0.7;
    transform: translateY(-50%) translateX(0);
}

.blob-footer {
    position: absolute;
    width: clamp(220px, 30vw, 360px);
    bottom: -80px;
    right: -60px;
    opacity: 0;
    transform: translateX(40px);
}

.is-visible .blob-footer {
    opacity: 0.55;
    transform: translateX(0);
}

/* ============================================================
   Lessons
   ============================================================ */
.lesson .lesson-inner {
    position: relative;
    z-index: 2;
    max-width: 760px;
    width: 100%;
}

.lesson-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 28px;
    font-family: var(--font-mono);
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--refutation-violet);
}

.lesson-number {
    font-weight: 600;
}

.lesson-divider {
    width: 32px;
    height: 1px;
    background: var(--refutation-violet);
    opacity: 0.5;
}

.lesson-tag {
    color: var(--scholar-brown);
    opacity: 0.7;
}

.section-white .lesson-tag {
    color: var(--ink-dark);
    opacity: 0.7;
}

.lesson-title {
    font-family: var(--font-headline);
    font-weight: 800;
    font-size: clamp(28px, 4.5vw, 56px);
    line-height: 1.15;
    letter-spacing: -0.02em;
    color: inherit;
    margin-bottom: 32px;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 700ms ease-out, transform 700ms ease-out;
}

.is-visible .lesson-title {
    opacity: 1;
    transform: translateY(0);
}

.lesson-body {
    font-family: var(--font-body);
    font-size: clamp(17px, 1.6vw, 19px);
    line-height: 1.85;
    margin-bottom: 22px;
    max-width: 640px;
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 700ms ease-out 150ms, transform 700ms ease-out 150ms;
}

.lesson-body.italic {
    font-style: italic;
    font-weight: 600;
    border-left: 2px solid var(--refutation-violet);
    padding-left: 20px;
    color: var(--scholar-brown);
}

.section-white .lesson-body.italic {
    color: var(--ink-dark);
}

.is-visible .lesson-body {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================================
   Underline-draw highlights — neon strikes on key terms
   ============================================================ */
.highlight {
    position: relative;
    display: inline-block;
    font-weight: 600;
    color: inherit;
}

.highlight::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -2px;
    width: 0;
    height: 3px;
    background: var(--refutation-violet);
    border-radius: 2px;
    transition: width 0.3s ease;
}

.highlight.is-drawn::after {
    width: 100%;
}

/* ============================================================
   Fallacy list (Lesson 02)
   ============================================================ */
.fallacy-list {
    list-style: none;
    margin-top: 32px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    max-width: 720px;
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 700ms ease-out 300ms, transform 700ms ease-out 300ms;
}

.is-visible .fallacy-list {
    opacity: 1;
    transform: translateY(0);
}

.fallacy-list li {
    display: flex;
    flex-direction: column;
    gap: 6px;
    padding: 18px 20px;
    background: rgba(254, 252, 248, 0.55);
    border-left: 3px solid var(--refutation-violet);
    backdrop-filter: blur(2px);
}

.fallacy-name {
    font-family: var(--font-headline);
    font-weight: 700;
    font-size: 16px;
    color: var(--scholar-brown);
    letter-spacing: 0.01em;
}

.fallacy-desc {
    font-family: var(--font-body);
    font-size: 15px;
    font-style: italic;
    color: var(--scholar-brown);
    opacity: 0.8;
    line-height: 1.5;
}

/* ============================================================
   Strike demo (Lesson 03)
   ============================================================ */
.strike-demo {
    margin-top: 36px;
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 700ms ease-out 300ms, transform 700ms ease-out 300ms;
}

.is-visible .strike-demo {
    opacity: 1;
    transform: translateY(0);
}

.strike-card {
    position: relative;
    padding: 28px 32px;
    background: rgba(245, 236, 215, 0.5);
    border: 1px solid rgba(139, 92, 246, 0.18);
    max-width: 640px;
}

.strike-claim {
    font-family: var(--font-body);
    font-size: 18px;
    font-style: italic;
    color: var(--ink-dark);
    line-height: 1.5;
    position: relative;
    z-index: 1;
}

.strike-line {
    position: absolute;
    left: 24px;
    right: 24px;
    top: 28px;
    width: calc(100% - 48px);
    height: 60px;
    pointer-events: none;
    z-index: 2;
}

.strike-line line {
    stroke-dasharray: 600;
    stroke-dashoffset: 600;
    transition: stroke-dashoffset 600ms ease-out 200ms;
    filter: drop-shadow(0 0 4px rgba(139, 92, 246, 0.5));
}

.is-visible .strike-line line {
    stroke-dashoffset: 0;
}

.strike-counter {
    margin-top: 24px;
    font-family: var(--font-body);
    font-size: 17px;
    line-height: 1.7;
    color: var(--ink-dark);
    border-top: 1px dashed rgba(139, 92, 246, 0.3);
    padding-top: 20px;
}

.strike-marker {
    display: inline-block;
    font-family: var(--font-headline);
    font-weight: 800;
    color: var(--refutation-violet);
    font-size: 16px;
    margin-right: 8px;
    letter-spacing: 0.05em;
}

/* ============================================================
   Arena — argument graph
   ============================================================ */
.arena {
    flex-direction: column;
    gap: 48px;
    padding-top: 100px;
    padding-bottom: 100px;
}

.arena-header {
    position: relative;
    z-index: 2;
    max-width: 760px;
    text-align: center;
    margin: 0 auto;
}

.arena-header .lesson-number {
    display: block;
    margin-bottom: 16px;
    font-family: var(--font-mono);
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--refutation-violet);
}

.arena-header .lesson-title {
    text-align: center;
}

.arena-header .lesson-body {
    margin: 0 auto;
    text-align: center;
}

.arena-canvas {
    position: relative;
    z-index: 2;
    width: 100%;
    max-width: 880px;
    margin: 0 auto;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 800ms ease-out 250ms, transform 800ms ease-out 250ms;
}

.is-visible .arena-canvas {
    opacity: 1;
    transform: translateY(0);
}

.argument-graph {
    width: 100%;
    height: auto;
}

.graph-blobs .blob-node {
    fill: var(--blob-lavender);
    opacity: 0.85;
}

.graph-blobs .blob-pivot {
    fill: var(--blob-lavender);
    stroke: var(--refutation-violet);
    stroke-width: 2;
    opacity: 0.95;
}

.graph-blobs .blob-refuted {
    fill: rgba(239, 68, 68, 0.18);
    stroke: var(--strike-red);
    stroke-width: 2;
    stroke-dasharray: 4 4;
}

.graph-lines .line-active {
    stroke-dasharray: 400;
    stroke-dashoffset: 400;
    transition: stroke-dashoffset 900ms ease-out;
}

.graph-lines .line-refuted {
    stroke: var(--scholar-brown);
    stroke-dasharray: 4 6;
    opacity: 0.45;
}

.is-visible .graph-lines .line-active {
    stroke-dashoffset: 0;
}

.graph-strike line {
    stroke-dasharray: 220;
    stroke-dashoffset: 220;
    transition: stroke-dashoffset 700ms ease-out 900ms;
    filter: drop-shadow(0 0 6px rgba(239, 68, 68, 0.5));
}

.is-visible .graph-strike line {
    stroke-dashoffset: 0;
}

.arena-legend {
    display: flex;
    justify-content: center;
    gap: 32px;
    margin-top: 24px;
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--scholar-brown);
    opacity: 0.75;
}

.legend-item {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.legend-swatch {
    display: inline-block;
    width: 24px;
    height: 3px;
    border-radius: 2px;
}

.legend-swatch.swatch-active {
    background: var(--refutation-violet);
}

.legend-swatch.swatch-refuted {
    background: var(--strike-red);
    background-image: linear-gradient(90deg, var(--strike-red) 60%, transparent 60%);
    background-size: 6px 3px;
}

/* ============================================================
   Footer — Scholar's bench
   ============================================================ */
.footer-section {
    min-height: 60vh;
    text-align: center;
}

.footer-inner {
    position: relative;
    z-index: 2;
    max-width: 600px;
}

.footer-mark {
    font-family: var(--font-headline);
    font-weight: 800;
    font-size: clamp(48px, 7vw, 88px);
    color: var(--scholar-brown);
    line-height: 1;
    margin-bottom: 24px;
}

.footer-mark .highlight {
    color: var(--scholar-brown);
}

.footer-mark .highlight::after {
    height: 4px;
    bottom: -6px;
}

.footer-line {
    font-family: var(--font-body);
    font-style: italic;
    font-size: 19px;
    color: var(--scholar-brown);
    opacity: 0.85;
    margin-bottom: 32px;
}

.footer-meta {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--scholar-brown);
    opacity: 0.6;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 24px;
}

.footer-dot {
    color: var(--refutation-violet);
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 720px) {
    .blob-side, .blob-side.blob-right {
        display: none;
    }
    .lesson-meta {
        flex-wrap: wrap;
        gap: 8px;
    }
    .lesson-divider {
        display: none;
    }
    .arena-legend {
        flex-direction: column;
        gap: 12px;
        align-items: center;
    }
}