/* ==========================================================================
   paradaigm.com  --  isometric scholasticism, horizontal panorama
   palette:
     #5B4A8A  Scholar Violet
     #D4A0A0  Lectern Rose
     #8BA89A  Blackboard Sage
     #F5F0E8  Parchment Cream
     #2C2440  Ink Dusk
     #E8C87A  Chalk Amber
     #7A9BC8  Thesis Blue
     #B8B0C4  Dust Grey
   typography: Commissioner (variable, 100-900) + Inconsolata (mono accents)
   ========================================================================== */

:root {
    --c-violet: #5B4A8A;
    --c-rose: #D4A0A0;
    --c-sage: #8BA89A;
    --c-cream: #F5F0E8;
    --c-ink: #2C2440;
    --c-amber: #E8C87A;
    --c-blue: #7A9BC8;
    --c-grey: #B8B0C4;
    --c-chalk-white: #F0EBF5;

    --font-display: "Commissioner", "Inter", "Lora", system-ui, sans-serif;
    --font-mono: "Inconsolata", "Space Mono", ui-monospace, monospace;

    --section-w: 165vw;
    --total-w: calc(var(--section-w) * 6);

    --iso-tilt-x: 30deg;
    --iso-tilt-z: -45deg;
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
    overflow: hidden;
    height: 100%;
    width: 100%;
    background: var(--c-cream);
    color: var(--c-violet);
    font-family: var(--font-display);
    font-weight: 300;
    -webkit-font-smoothing: antialiased;
}

body {
    overscroll-behavior: none;
    cursor: grab;
}

body.is-dragging {
    cursor: grabbing;
    user-select: none;
}

/* ==========================================================================
   Wordmark
   ========================================================================== */
.wordmark {
    position: fixed;
    top: 26px;
    left: 36px;
    z-index: 50;
    font-family: var(--font-display);
    font-weight: 800;
    letter-spacing: -0.03em;
    font-size: 1.35rem;
    color: var(--c-violet);
    user-select: none;
}
.wordmark .wm-fix {
    color: var(--c-rose);
    font-weight: 800;
}
.wordmark .wm-dot {
    color: var(--c-amber);
    font-weight: 900;
    margin: 0 0.05em;
}
.wordmark .wm-tld {
    font-family: var(--font-mono);
    font-weight: 400;
    font-size: 0.85rem;
    color: var(--c-grey);
    letter-spacing: 0.02em;
    vertical-align: 0.18em;
}

/* ==========================================================================
   Bookmark / index tab navigation
   ========================================================================== */
.bookmark-nav {
    position: fixed;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    z-index: 45;
    display: flex;
    gap: 6px;
    padding: 0;
    pointer-events: auto;
}

.bookmark-tab {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1px;
    padding: 14px 16px 12px;
    background: var(--c-cream);
    border: 1px solid rgba(91, 74, 138, 0.18);
    border-top: none;
    border-radius: 0 0 9px 9px;
    text-decoration: none;
    color: var(--c-violet);
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.74rem;
    letter-spacing: 0.04em;
    transition: all 380ms cubic-bezier(0.22, 1, 0.36, 1);
    transform: translateY(-2px);
    box-shadow: 0 4px 10px -6px rgba(44, 36, 64, 0.28);
}

.bookmark-tab .tab-no {
    font-family: var(--font-mono);
    font-weight: 400;
    font-size: 0.7rem;
    color: var(--c-grey);
    letter-spacing: 0.06em;
}
.bookmark-tab .tab-label {
    font-weight: 200;
    font-size: 0.78rem;
    text-transform: lowercase;
    color: var(--c-violet);
}

.bookmark-tab:hover {
    transform: translateY(2px);
    background: #FBF7EF;
    border-color: rgba(91, 74, 138, 0.4);
}

.bookmark-tab.active {
    border-bottom: 2px solid var(--c-amber);
    background: #FBF7EF;
    transform: translateY(4px);
}
.bookmark-tab.active .tab-label {
    font-weight: 500;
}

/* ==========================================================================
   Reading progress thread
   ========================================================================== */
.progress-rail {
    position: fixed;
    bottom: 22px;
    left: 7vw;
    right: 7vw;
    height: 22px;
    z-index: 40;
    pointer-events: none;
}

.progress-fill {
    position: absolute;
    top: 50%;
    left: 0;
    height: 1px;
    background: var(--c-amber);
    width: 0%;
    transform: translateY(-50%);
    transition: width 80ms linear;
}
.progress-rail::before {
    content: "";
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 1px;
    background: rgba(91, 74, 138, 0.18);
    transform: translateY(-50%);
}

.progress-nodes {
    position: absolute;
    inset: 0;
}
.progress-node {
    position: absolute;
    top: 50%;
    width: 8px;
    height: 8px;
    margin-left: -4px;
    margin-top: -4px;
    border-radius: 50%;
    background: var(--c-cream);
    border: 1.5px solid var(--c-violet);
    transition: transform 240ms ease, background 240ms ease, border-color 240ms ease;
}
.progress-node.active {
    background: var(--c-amber);
    border-color: var(--c-amber);
    animation: nodepulse 2s ease-in-out infinite;
}
@keyframes nodepulse {
    0%, 100% { transform: scale(1); }
    50%      { transform: scale(1.2); }
}

/* ==========================================================================
   Scroll hint
   ========================================================================== */
.scroll-hint {
    position: fixed;
    bottom: 60px;
    left: 36px;
    z-index: 45;
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.78rem;
    color: var(--c-violet);
    letter-spacing: 0.04em;
    opacity: 0.8;
    transition: opacity 600ms ease;
}
.scroll-hint.fade {
    opacity: 0;
}
.scroll-hint .hint-line {
    display: inline-block;
    width: 28px;
    height: 1px;
    background: var(--c-violet);
}
.scroll-hint .hint-arrow {
    font-family: var(--font-mono);
    color: var(--c-amber);
    font-weight: 600;
    animation: arrowSlide 2.4s ease-in-out infinite;
}
@keyframes arrowSlide {
    0%, 100% { transform: translateX(0); }
    50%      { transform: translateX(6px); }
}

/* ==========================================================================
   Panorama track  (the horizontal canvas)
   ========================================================================== */
.panorama {
    position: fixed;
    inset: 0;
    overflow: hidden;
    background:
        radial-gradient(ellipse 80% 60% at 50% 50%, #FBF7EF 0%, var(--c-cream) 60%, #ECE3D6 100%);
}

.panorama-track {
    position: relative;
    height: 100%;
    width: var(--total-w);
    display: flex;
    flex-direction: row;
    will-change: transform;
    transform: translate3d(0, 0, 0);
}

/* background ghost numerals (between rooms, lightest layer) */
.bg-numerals {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}
.ghost-num {
    position: absolute;
    top: 14vh;
    font-family: var(--font-display);
    font-weight: 100;
    font-size: 26vw;
    line-height: 0.9;
    color: var(--c-violet);
    opacity: 0.06;
    letter-spacing: -0.04em;
    user-select: none;
}

/* ==========================================================================
   Background plane (large isometric structures, slow parallax)
   ========================================================================== */
.bg-plane {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
}

.bg-iso {
    position: absolute;
    width: 56vw;
    height: 60vh;
    opacity: 0.18;
}
.bg-iso .iso-stroke {
    fill: none;
    stroke: var(--c-violet);
    stroke-width: 0.8;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.bg-iso-1 { top: 18vh;  left: 8vw;   transform: rotate(0deg); }
.bg-iso-2 { top: 14vh;  left: 200vw; opacity: 0.16; }
.bg-iso-3 { top: 22vh;  left: 365vw; opacity: 0.20; }
.bg-iso-4 { top: 16vh;  left: 530vw; opacity: 0.18; }
.bg-iso-5 { top: 20vh;  left: 695vw; opacity: 0.20; }
.bg-iso-6 { top: 18vh;  left: 850vw; opacity: 0.22; }

/* Animated stroke draw */
.bg-iso .iso-stroke path,
.bg-iso .iso-stroke ellipse,
.bg-iso .iso-stroke circle {
    stroke-dasharray: 2400;
    stroke-dashoffset: 2400;
    transition: stroke-dashoffset 1400ms cubic-bezier(0.22, 1, 0.36, 1);
}
.bg-iso.in-view .iso-stroke path,
.bg-iso.in-view .iso-stroke ellipse,
.bg-iso.in-view .iso-stroke circle {
    stroke-dashoffset: 0;
}

/* ==========================================================================
   Room (section) base
   ========================================================================== */
.room {
    position: relative;
    flex: 0 0 var(--section-w);
    width: var(--section-w);
    height: 100vh;
    padding: 0;
    overflow: visible;
    z-index: 2;
}

.room-floor {
    position: absolute;
    left: -10%;
    right: -10%;
    bottom: 0;
    height: 38vh;
    transform: perspective(1200px) rotateX(58deg);
    transform-origin: bottom center;
    background:
        linear-gradient(180deg, transparent 0%, rgba(91, 74, 138, 0.08) 100%);
    border-top: 1px solid rgba(91, 74, 138, 0.18);
    pointer-events: none;
    z-index: 1;
}
.room-floor::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        repeating-linear-gradient(45deg,
            rgba(91, 74, 138, 0.08) 0,
            rgba(91, 74, 138, 0.08) 1px,
            transparent 1px,
            transparent 80px),
        repeating-linear-gradient(-45deg,
            rgba(91, 74, 138, 0.08) 0,
            rgba(91, 74, 138, 0.08) 1px,
            transparent 1px,
            transparent 80px);
    opacity: 0.7;
}

/* per-section floor wash */
.floor-2 { background: linear-gradient(180deg, transparent 0%, rgba(139, 168, 154, 0.18) 100%); }
.floor-3 { background: linear-gradient(180deg, transparent 0%, rgba(122, 155, 200, 0.18) 100%); }
.floor-4 { background: linear-gradient(180deg, transparent 0%, rgba(212, 160, 160, 0.18) 100%); }
.floor-5 { background: linear-gradient(180deg, transparent 0%, rgba(232, 200, 122, 0.20) 100%); }
.floor-6 { background: linear-gradient(180deg, transparent 0%, rgba(44, 36, 64, 0.30) 100%); }

/* folio (page-number style label, bottom-left of each section) */
.folio {
    position: absolute;
    left: 6vw;
    bottom: 60px;
    font-family: var(--font-mono);
    font-weight: 300;
    font-size: 0.78rem;
    color: var(--c-violet);
    letter-spacing: 0.08em;
    text-transform: lowercase;
    opacity: 0.6;
    z-index: 5;
}
.room-commons .folio { color: var(--c-cream); opacity: 0.7; }

/* ==========================================================================
   Section 1: Portico  --  title block
   ========================================================================== */
.title-block {
    position: absolute;
    top: 22vh;
    left: 8vw;
    width: 70vw;
    z-index: 6;
}
.display-title {
    margin: 0;
    font-family: var(--font-display);
    font-weight: 800;
    font-size: clamp(3.4rem, 6vw, 6rem);
    line-height: 1.02;
    letter-spacing: -0.025em;
    color: var(--c-violet);
}
.display-title .title-line {
    display: block;
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1),
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1);
}
.display-title .line-1 { transition-delay: 80ms;  color: var(--c-violet); }
.display-title .line-2 { transition-delay: 240ms; color: var(--c-rose); font-weight: 400; font-style: italic; letter-spacing: -0.01em; }
.display-title .line-3 { transition-delay: 400ms; color: var(--c-violet); }

.room-portico.in-view .display-title .title-line {
    opacity: 1;
    transform: translateY(0);
}

.title-sub {
    margin: 36px 0 0;
    max-width: 38ch;
    font-family: var(--font-display);
    font-weight: 300;
    font-size: 1.05rem;
    line-height: 1.72;
    letter-spacing: 0.005em;
    color: var(--c-ink);
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 600ms,
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1) 600ms;
}
.room-portico.in-view .title-sub {
    opacity: 1;
    transform: translateY(0);
}
.title-sub .sub-mark {
    color: var(--c-amber);
    font-weight: 600;
    margin-right: 8px;
    font-size: 1.2rem;
    vertical-align: -0.05em;
}

/* ==========================================================================
   Iso card  (text card placed on isometric plane)
   ========================================================================== */
.iso-card {
    position: absolute;
    width: 320px;
    padding: 22px 24px 22px;
    background: rgba(255, 252, 246, 0.86);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    border: 1px solid rgba(91, 74, 138, 0.22);
    border-radius: 2px;
    box-shadow:
        0 18px 30px -22px rgba(44, 36, 64, 0.35),
        0 1px 0 rgba(255, 255, 255, 0.8) inset;
    color: var(--c-ink);
    z-index: 8;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 800ms cubic-bezier(0.22, 1, 0.36, 1),
                transform 800ms cubic-bezier(0.22, 1, 0.36, 1);
}

.room.in-view .iso-card {
    opacity: 1;
    transform: translateY(0);
}
.room.in-view .iso-card.card-A,    .room.in-view .iso-card.card-2A,
.room.in-view .iso-card.card-3A,   .room.in-view .iso-card.card-4A,
.room.in-view .iso-card.card-5A {
    transition-delay: 800ms;
}
.room.in-view .iso-card.card-B,    .room.in-view .iso-card.card-2B,
.room.in-view .iso-card.card-3B,   .room.in-view .iso-card.card-4B,
.room.in-view .iso-card.card-5B {
    transition-delay: 980ms;
}

.iso-card .card-label {
    display: inline-block;
    font-family: var(--font-display);
    font-weight: 500;
    font-variant: small-caps;
    font-size: 0.72rem;
    letter-spacing: 0.16em;
    color: var(--c-rose);
    margin-bottom: 8px;
    text-transform: lowercase;
}
.iso-card .card-body {
    margin: 0;
    font-family: var(--font-display);
    font-weight: 300;
    font-size: 1.02rem;
    line-height: 1.62;
    letter-spacing: 0.005em;
    color: var(--c-ink);
}
.iso-card .card-foot {
    display: block;
    margin-top: 12px;
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.78rem;
    line-height: 1.5;
    color: var(--c-grey);
    letter-spacing: 0.01em;
}

/* card placements per section */
.card-A   { top: 56vh; left: 12vw; }
.card-B   { top: 30vh; left: 96vw; transform-origin: left center; }

.card-2A  { top: 30vh; left: 18vw; }
.card-2B  { top: 58vh; left: 78vw; }

.card-3A  { top: 26vh; left: 80vw; }
.card-3B  { top: 58vh; left: 22vw; }

.card-4A  { top: 32vh; left: 16vw; }
.card-4B  { top: 60vh; left: 90vw; }

.card-5A  { top: 30vh; left: 80vw; }
.card-5B  { top: 60vh; left: 18vw; }

/* ==========================================================================
   Prism (gradient mesh polyhedron)
   ========================================================================== */
.prism {
    position: absolute;
    width: 220px;
    height: 220px;
    z-index: 4;
    transform-style: preserve-3d;
    perspective: 1000px;
    pointer-events: none;
    opacity: 0;
    transition: opacity 1200ms cubic-bezier(0.22, 1, 0.36, 1) 400ms;
}
.room.in-view .prism { opacity: 1; }

.prism-face {
    position: absolute;
    inset: 0;
    border-radius: 4px;
    mix-blend-mode: multiply;
}
.prism-face.f1 {
    background:
        radial-gradient(circle at 30% 30%, rgba(232, 200, 122, 0.85) 0%, rgba(232, 200, 122, 0) 60%),
        radial-gradient(circle at 70% 70%, rgba(212, 160, 160, 0.65) 0%, rgba(212, 160, 160, 0) 60%);
    transform: rotateY(0deg) translateZ(40px);
}
.prism-face.f2 {
    background:
        radial-gradient(circle at 60% 30%, rgba(122, 155, 200, 0.75) 0%, rgba(122, 155, 200, 0) 65%),
        radial-gradient(circle at 30% 80%, rgba(139, 168, 154, 0.6) 0%, rgba(139, 168, 154, 0) 65%);
    transform: rotateY(60deg) translateZ(40px);
}
.prism-face.f3 {
    background:
        radial-gradient(circle at 50% 50%, rgba(91, 74, 138, 0.65) 0%, rgba(91, 74, 138, 0) 65%),
        radial-gradient(circle at 80% 20%, rgba(232, 200, 122, 0.45) 0%, rgba(232, 200, 122, 0) 65%);
    transform: rotateY(-60deg) translateZ(40px);
}
.prism-face.f4 {
    background:
        radial-gradient(circle at 40% 40%, rgba(232, 200, 122, 0.7) 0%, rgba(232, 200, 122, 0) 65%),
        radial-gradient(circle at 70% 70%, rgba(122, 155, 200, 0.55) 0%, rgba(122, 155, 200, 0) 65%);
    transform: rotateZ(45deg);
}

.prism {
    animation: prismDrift 14s ease-in-out infinite;
}
@keyframes prismDrift {
    0%, 100% { transform: translate3d(0, 0, 0) rotateX(20deg) rotateY(0deg); }
    50%      { transform: translate3d(0, -8px, 0) rotateX(20deg) rotateY(20deg); }
}

.prism-portico { top: 20vh;  left: 100vw; width: 240px; height: 240px; }
.prism-2       { top: 18vh;  left: 110vw; width: 200px; height: 200px; }
.prism-3       { top: 60vh;  left: 60vw;  width: 220px; height: 220px; }
.prism-4       { top: 22vh;  left: 70vw;  width: 240px; height: 240px; }
.prism-5       { top: 22vh;  left: 38vw;  width: 220px; height: 220px; }
.prism-commons { top: 20vh;  right: 12vw; width: 280px; height: 280px; }

/* ==========================================================================
   Book stack  (gradient mesh books, isometric)
   ========================================================================== */
.book-stack {
    position: absolute;
    z-index: 3;
    transform: rotateX(60deg) rotateZ(-45deg);
    transform-style: preserve-3d;
    pointer-events: auto;
    opacity: 0;
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 700ms,
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1) 700ms;
}
.room.in-view .book-stack {
    opacity: 1;
}

.book {
    position: relative;
    width: 220px;
    height: 28px;
    margin-bottom: 4px;
    border-radius: 3px;
    box-shadow:
        0 6px 14px -8px rgba(44, 36, 64, 0.45),
        inset 0 -2px 0 rgba(0, 0, 0, 0.08),
        inset 0 1px 0 rgba(255, 255, 255, 0.18);
    transition: transform 380ms ease;
}
.book:hover { transform: translateX(6px); }

.book .spine {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    transform-origin: 0 50%;
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.8rem;
    letter-spacing: 0.06em;
    color: rgba(245, 240, 232, 0.92);
    white-space: nowrap;
    text-transform: lowercase;
}
.book .spine::before {
    content: "";
    position: absolute;
    left: -12px;
    top: 50%;
    width: 6px;
    height: 1px;
    background: var(--c-amber);
    opacity: 0.7;
}

.book.b1 { background: linear-gradient(135deg, #5B4A8A 0%, #7A6AAE 60%, #483A70 100%); width: 240px; }
.book.b2 { background: linear-gradient(135deg, #D4A0A0 0%, #E2B3B3 60%, #B98484 100%); width: 200px; }
.book.b3 { background: linear-gradient(135deg, #8BA89A 0%, #A9C2B3 60%, #6E8C7E 100%); width: 230px; }
.book.b4 { background: linear-gradient(135deg, #7A9BC8 0%, #99B7E0 60%, #5C7DAA 100%); width: 215px; }

.stack-portico { top: 70vh;  left: 70vw; }
.stack-2       { top: 68vh;  left: 50vw; }
.stack-4       { top: 64vh;  left: 50vw; }

/* ==========================================================================
   Lectern  (open-volume quote)
   ========================================================================== */
.lectern {
    position: absolute;
    z-index: 4;
    width: 380px;
    height: 220px;
    transform-style: preserve-3d;
    opacity: 0;
    transform: translateY(30px) rotateX(8deg) rotateZ(-2deg);
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 600ms,
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1) 600ms;
}
.room.in-view .lectern {
    opacity: 1;
    transform: translateY(0) rotateX(8deg) rotateZ(-2deg);
}

.lectern::before {
    content: "";
    position: absolute;
    left: 20%;
    right: 20%;
    bottom: -22px;
    height: 22px;
    background: linear-gradient(180deg, #B98C75 0%, #8B6651 100%);
    transform: skewX(-10deg);
    border-radius: 0 0 2px 2px;
    box-shadow: 0 8px 18px -10px rgba(44, 36, 64, 0.4);
}

.lectern-page {
    position: absolute;
    inset: 0;
    background:
        linear-gradient(180deg, #FBF7EF 0%, #F0E9DA 100%);
    border: 1px solid rgba(91, 74, 138, 0.18);
    border-radius: 3px;
    padding: 26px 30px;
    box-shadow:
        inset 0 0 30px rgba(212, 160, 160, 0.18),
        0 12px 24px -16px rgba(44, 36, 64, 0.35);
}
.lectern-page::before {
    content: "";
    position: absolute;
    left: 50%;
    top: 18px;
    bottom: 18px;
    width: 1px;
    background: rgba(91, 74, 138, 0.18);
    transform: translateX(-50%);
}

.lectern-eyebrow {
    margin: 0 0 8px;
    font-family: var(--font-mono);
    font-weight: 400;
    font-size: 0.74rem;
    letter-spacing: 0.08em;
    color: var(--c-grey);
    text-transform: lowercase;
}
.lectern-quote {
    margin: 0;
    font-family: var(--font-display);
    font-weight: 400;
    font-style: italic;
    font-size: 1.08rem;
    line-height: 1.55;
    color: var(--c-violet);
    max-width: 30ch;
}
.lectern-cite {
    margin: 14px 0 0;
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.82rem;
    letter-spacing: 0.02em;
    color: var(--c-grey);
}

.lectern-2 { top: 52vh; left: 50vw; }
.lectern-3 { top: 26vh; left: 24vw; }

/* ==========================================================================
   Blackboard  (isometric, with chalk equations)
   ========================================================================== */
.blackboard {
    position: absolute;
    z-index: 4;
    width: 420px;
    height: 240px;
    background:
        radial-gradient(ellipse at 30% 30%, rgba(255, 255, 255, 0.06) 0%, transparent 60%),
        linear-gradient(135deg, #2F4A3F 0%, #1F352C 100%);
    border: 8px solid #6B4D38;
    border-radius: 4px;
    transform: rotateX(8deg) rotateY(-12deg);
    transform-style: preserve-3d;
    box-shadow:
        0 20px 35px -22px rgba(44, 36, 64, 0.55),
        inset 0 0 60px rgba(0, 0, 0, 0.25);
    opacity: 0;
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 500ms;
}
.room.in-view .blackboard { opacity: 1; }

.blackboard .chalk-eq {
    position: absolute;
    font-family: var(--font-display);
    font-weight: 300;
    font-size: 1.2rem;
    color: rgba(240, 235, 245, 0.88);
    letter-spacing: 0.02em;
    text-shadow: 0 0 8px rgba(240, 235, 245, 0.3);
}
.blackboard .c-eq-1 { top: 30px; left: 30px; }
.blackboard .c-eq-2 { top: 90px; left: 50px; font-size: 1.05rem; }
.blackboard .chalk-line {
    position: absolute;
    height: 1px;
    background: rgba(240, 235, 245, 0.5);
}
.blackboard .c-l-1 { top: 60px; left: 30px; width: 220px; }
.blackboard .c-l-2 { top: 130px; left: 60px; width: 140px; }

.blackboard .chalk-mark {
    position: absolute;
    font-family: var(--font-mono);
    font-size: 1.3rem;
    color: rgba(232, 200, 122, 0.85);
    text-shadow: 0 0 8px rgba(232, 200, 122, 0.4);
}
.blackboard .c-m-1 { right: 26px; top: 28px; }
.blackboard .c-m-2 { right: 26px; bottom: 24px; }

.board-2 { top: 22vh; left: 96vw; }
.board-3 { top: 60vh; left: 100vw; width: 360px; height: 200px; }
.board-5 { top: 60vh; left: 96vw; width: 360px; height: 180px; }

/* chalk concept tree (board-3) */
.chalk-tree {
    position: absolute;
    bottom: 18px;
    right: 22px;
    width: 150px;
    height: 110px;
}
.chalk-tree .branch {
    position: absolute;
    background: rgba(240, 235, 245, 0.8);
}
.chalk-tree .b-root { left: 50%; top: 0; width: 1px; height: 30px; transform: translateX(-50%); }
.chalk-tree .b-l    { left: 22%; top: 26px; width: 56%; height: 1px; }
.chalk-tree .b-r    { right: 22%; top: 60px; width: 56%; height: 1px; }
.chalk-tree .b-ll   { left: 22%; top: 26px; width: 1px; height: 34px; }
.chalk-tree .b-rr   { right: 22%; top: 60px; width: 1px; height: 34px; }

/* ==========================================================================
   Annotations / margin marks
   ========================================================================== */
.margin-mark {
    position: absolute;
    font-family: var(--font-display);
    font-weight: 400;
    color: var(--c-amber);
    font-size: 1.4rem;
    z-index: 7;
    pointer-events: none;
    opacity: 0.85;
}
.mm-1 { top: 32vh; left: 76vw; transform: rotate(-8deg); }
.mm-2 { top: 78vh; left: 38vw; color: var(--c-rose); transform: rotate(6deg); }

.annotation {
    position: absolute;
    z-index: 7;
    display: flex;
    align-items: baseline;
    gap: 8px;
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.82rem;
    line-height: 1.5;
    color: var(--c-grey);
    letter-spacing: 0.01em;
    max-width: 22ch;
}
.annotation .ann-symbol {
    color: var(--c-rose);
    font-weight: 400;
    font-size: 0.95rem;
}
.annotation::before {
    content: "";
    position: absolute;
    left: -18px;
    top: 0.7em;
    width: 12px;
    height: 1px;
    background: var(--c-rose);
    opacity: 0.6;
}

.a-2-1 { top: 76vh; left: 30vw; }
.a-3-1 { top: 78vh; left: 70vw; }
.a-4-1 { top: 78vh; left: 64vw; }
.a-5-1 { top: 80vh; left: 60vw; color: rgba(245, 240, 232, 0.7); }
.a-6-1 { top: 82vh; left: 22vw; color: rgba(245, 240, 232, 0.7); }

/* ==========================================================================
   Section heads (II..V)
   ========================================================================== */
.section-head {
    position: absolute;
    top: 18vh;
    left: 8vw;
    width: 44vw;
    z-index: 6;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1),
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1);
}
.section-head.head-right {
    left: auto;
    right: 8vw;
    text-align: right;
}
.room.in-view .section-head {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 280ms;
}

.section-label {
    display: inline-block;
    margin-bottom: 14px;
    padding: 4px 10px;
    border: 1px solid rgba(91, 74, 138, 0.4);
    border-radius: 1px;
    font-family: var(--font-display);
    font-weight: 500;
    font-variant: small-caps;
    font-size: 0.74rem;
    letter-spacing: 0.18em;
    color: var(--c-violet);
    text-transform: lowercase;
}
.section-label.label-light {
    color: var(--c-cream);
    border-color: rgba(245, 240, 232, 0.4);
}

.section-title {
    margin: 0;
    font-family: var(--font-display);
    font-weight: 800;
    font-size: clamp(3rem, 5vw, 5.2rem);
    line-height: 1.02;
    letter-spacing: -0.025em;
    color: var(--c-violet);
}
.room-rational .section-title    { color: var(--c-blue); }
.room-empirical .section-title   { color: var(--c-sage); }
.room-phenomenal .section-title  { color: var(--c-rose); }
.room-pragmatic .section-title   { color: var(--c-amber); }

.section-deck {
    margin: 22px 0 0;
    max-width: 38ch;
    font-family: var(--font-display);
    font-weight: 300;
    font-size: 1.05rem;
    line-height: 1.72;
    letter-spacing: 0.005em;
    color: var(--c-ink);
}
.section-head.head-right .section-deck {
    margin-left: auto;
}

/* ==========================================================================
   Section 3 -- staircase (Escher hint)
   ========================================================================== */
.staircase {
    position: absolute;
    top: 58vh;
    left: 60vw;
    width: 320px;
    height: 220px;
    z-index: 3;
    transform-style: preserve-3d;
    transform: rotateX(50deg) rotateZ(-45deg);
    opacity: 0;
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 500ms;
}
.room-rational.in-view .staircase { opacity: 1; }

.stair-step {
    position: absolute;
    left: 0;
    width: 200px;
    height: 14px;
    background: linear-gradient(135deg, rgba(122, 155, 200, 0.85) 0%, rgba(91, 74, 138, 0.85) 100%);
    border-radius: 2px;
    box-shadow: 0 4px 8px -4px rgba(44, 36, 64, 0.5);
}
.staircase .s1 { bottom: 0;   transform: translateZ(0); }
.staircase .s2 { bottom: 18px; transform: translateZ(20px); }
.staircase .s3 { bottom: 36px; transform: translateZ(40px); }
.staircase .s4 { bottom: 54px; transform: translateZ(60px); }
.staircase .s5 { bottom: 72px; transform: translateZ(80px); }
.staircase .s6 { bottom: 90px; transform: translateZ(100px); }

/* ==========================================================================
   Section 4 -- alcove
   ========================================================================== */
.alcove {
    position: absolute;
    top: 50vh;
    left: 50vw;
    width: 300px;
    height: 320px;
    z-index: 3;
    transform: rotateY(-18deg) rotateX(4deg);
    transform-style: preserve-3d;
    opacity: 0;
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 500ms;
}
.room-phenomenal.in-view .alcove { opacity: 1; }

.alcove-arch {
    position: absolute;
    inset: 0 30px 60px 30px;
    border: 2px solid var(--c-rose);
    border-bottom: none;
    border-radius: 130px 130px 0 0;
    background:
        radial-gradient(ellipse 60% 50% at 50% 60%, rgba(212, 160, 160, 0.12), transparent 70%);
}
.alcove-bench {
    position: absolute;
    bottom: 30px;
    left: 50px;
    right: 50px;
    height: 22px;
    background: linear-gradient(180deg, #B98C75, #8B6651);
    border-radius: 2px;
    box-shadow: 0 6px 12px -8px rgba(44, 36, 64, 0.5);
}
.alcove-window {
    position: absolute;
    top: 60px;
    left: 70px;
    right: 70px;
    bottom: 80px;
    background:
        linear-gradient(180deg, rgba(232, 200, 122, 0.35), rgba(212, 160, 160, 0.18));
    border: 1px solid rgba(91, 74, 138, 0.3);
    display: grid;
    grid-template: repeat(2, 1fr) / repeat(2, 1fr);
    gap: 1px;
}
.window-pane {
    background:
        linear-gradient(135deg, rgba(245, 240, 232, 0.65) 0%, rgba(232, 200, 122, 0.25) 100%);
}
.window-pane.p2 { background: linear-gradient(135deg, rgba(212, 160, 160, 0.45) 0%, rgba(245, 240, 232, 0.4) 100%); }
.window-pane.p3 { background: linear-gradient(135deg, rgba(232, 200, 122, 0.4) 0%, rgba(212, 160, 160, 0.3) 100%); }
.window-pane.p4 { background: linear-gradient(135deg, rgba(245, 240, 232, 0.55) 0%, rgba(122, 155, 200, 0.25) 100%); }

/* ==========================================================================
   Section 5 -- forum table
   ========================================================================== */
.forum-table {
    position: absolute;
    top: 58vh;
    left: 24vw;
    width: 360px;
    height: 200px;
    z-index: 3;
    transform-style: preserve-3d;
    transform: rotateX(50deg) rotateZ(-25deg);
    opacity: 0;
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 500ms;
}
.room-pragmatic.in-view .forum-table { opacity: 1; }

.table-top {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 30% 30%, rgba(255, 255, 255, 0.2), transparent 50%),
        linear-gradient(135deg, #B98C75 0%, #8B6651 100%);
    border-radius: 2px;
    box-shadow:
        0 10px 20px -10px rgba(44, 36, 64, 0.45),
        inset 0 1px 0 rgba(255, 255, 255, 0.18);
}
.table-leg {
    position: absolute;
    width: 6px;
    height: 60px;
    background: linear-gradient(180deg, #8B6651, #5B4A3E);
    bottom: -60px;
}
.leg-l { left: 20px; }
.leg-r { right: 20px; }

.table-chair {
    position: absolute;
    width: 50px;
    height: 50px;
    border-radius: 4px;
    background: linear-gradient(135deg, var(--c-amber) 0%, #C2A05E 100%);
    box-shadow: 0 4px 8px -4px rgba(44, 36, 64, 0.4);
}
.chair-1 { top: -60px; left: 40px;  background: linear-gradient(135deg, var(--c-rose), #B98484); }
.chair-2 { top: -60px; left: 200px; background: linear-gradient(135deg, var(--c-sage), #6E8C7E); }
.chair-3 { bottom: -110px; left: 130px; background: linear-gradient(135deg, var(--c-blue), #5C7DAA); }

/* ==========================================================================
   Section 6 -- The Commons
   ========================================================================== */
.room-commons {
    background:
        linear-gradient(180deg, #1F1A2E 0%, #2C2440 60%, #1A1530 100%);
    color: var(--c-cream);
}
.room-commons .room-floor {
    background: linear-gradient(180deg, transparent, rgba(232, 200, 122, 0.18));
    border-top-color: rgba(232, 200, 122, 0.35);
}
.room-commons .room-floor::before {
    background-image:
        repeating-linear-gradient(45deg,
            rgba(232, 200, 122, 0.12) 0,
            rgba(232, 200, 122, 0.12) 1px,
            transparent 1px,
            transparent 80px),
        repeating-linear-gradient(-45deg,
            rgba(232, 200, 122, 0.12) 0,
            rgba(232, 200, 122, 0.12) 1px,
            transparent 1px,
            transparent 80px);
}

.commons-headline {
    position: absolute;
    top: 18vh;
    left: 8vw;
    width: 60vw;
    z-index: 6;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 240ms,
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1) 240ms;
}
.room-commons.in-view .commons-headline { opacity: 1; transform: translateY(0); }

.commons-title {
    margin: 0;
    font-family: var(--font-display);
    font-weight: 800;
    font-size: clamp(2.8rem, 4.6vw, 4.6rem);
    line-height: 1.04;
    letter-spacing: -0.02em;
    color: var(--c-cream);
}
.commons-sub {
    margin: 26px 0 0;
    max-width: 46ch;
    font-family: var(--font-display);
    font-weight: 300;
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--c-grey);
}

.commons-quartet {
    position: absolute;
    top: 60vh;
    left: 8vw;
    display: flex;
    gap: 28px;
    z-index: 6;
}
.quartet-card {
    width: 168px;
    padding: 22px 20px 24px;
    background: rgba(245, 240, 232, 0.06);
    border: 1px solid rgba(232, 200, 122, 0.4);
    border-radius: 2px;
    color: var(--c-cream);
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 800ms cubic-bezier(0.22, 1, 0.36, 1),
                transform 800ms cubic-bezier(0.22, 1, 0.36, 1),
                background 380ms ease;
}
.room-commons.in-view .quartet-card { opacity: 1; transform: translateY(0); }
.room-commons.in-view .q-1 { transition-delay: 600ms; }
.room-commons.in-view .q-2 { transition-delay: 720ms; }
.room-commons.in-view .q-3 { transition-delay: 840ms; }
.room-commons.in-view .q-4 { transition-delay: 960ms; }
.quartet-card:hover { background: rgba(232, 200, 122, 0.12); }

.quartet-card .q-roman {
    display: block;
    font-family: var(--font-mono);
    font-weight: 400;
    font-size: 0.78rem;
    letter-spacing: 0.1em;
    color: var(--c-amber);
    margin-bottom: 14px;
}
.quartet-card .q-name {
    display: block;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1.2rem;
    letter-spacing: -0.01em;
    color: var(--c-cream);
    margin-bottom: 6px;
}
.quartet-card .q-line {
    display: block;
    font-family: var(--font-display);
    font-weight: 200;
    font-variant: small-caps;
    font-size: 0.84rem;
    letter-spacing: 0.1em;
    color: var(--c-grey);
}

.commons-coda {
    position: absolute;
    bottom: 18vh;
    right: 10vw;
    max-width: 40ch;
    text-align: right;
    z-index: 6;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1) 1000ms,
                transform 900ms cubic-bezier(0.22, 1, 0.36, 1) 1000ms;
}
.room-commons.in-view .commons-coda { opacity: 1; transform: translateY(0); }
.coda-mark {
    margin: 0 0 8px;
    font-family: var(--font-display);
    font-weight: 400;
    font-size: 1.6rem;
    color: var(--c-amber);
}
.coda-text {
    margin: 0;
    font-family: var(--font-display);
    font-weight: 300;
    font-style: italic;
    font-size: 1.15rem;
    line-height: 1.6;
    color: var(--c-cream);
}
.coda-sign {
    margin: 16px 0 0;
    font-family: var(--font-display);
    font-weight: 200;
    font-size: 0.86rem;
    color: var(--c-grey);
    letter-spacing: 0.02em;
}

/* commons-specific bookmark colors */
.room-commons .folio { color: var(--c-amber); opacity: 0.7; }

/* ==========================================================================
   Misc — reduce motion / touch
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
    .panorama-track,
    .display-title .title-line,
    .iso-card,
    .lectern,
    .blackboard,
    .prism,
    .book-stack,
    .section-head,
    .commons-headline,
    .quartet-card,
    .commons-coda,
    .alcove,
    .forum-table,
    .staircase {
        transition: none !important;
        animation: none !important;
    }
}

/* small viewports -- still horizontal, just denser */
@media (max-width: 760px) {
    :root { --section-w: 200vw; }
    .display-title { font-size: clamp(2.4rem, 8vw, 3.6rem); }
    .section-title { font-size: clamp(2rem, 7vw, 3rem); }
    .iso-card { width: 280px; }
    .bookmark-tab .tab-label { display: none; }
}