/* relative.quest - Bauhaus meets Isometric */

:root {
    --canvas: #fafafa;
    --signal-red: #d42828;
    --depth-blue: #2848a8;
    --measure-gold: #e8c828;
    --frame: #1a1a1a;
    --perspective: #b8b0a8;
    --horizon: #d8e4f0;
    --viewpoint: #3a8848;
    --skew-angle: 15deg;
}

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

body {
    font-family: 'Source Serif 4', serif;
    font-weight: 400;
    color: var(--frame);
    background-color: var(--canvas);
    overflow-x: hidden;
    line-height: 1.8;
    font-size: clamp(0.95rem, 1.1vw, 1.15rem);
}

h2, h3 {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 700;
}

code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
}

/* Section 1: Observer's Platform */
#observer-platform {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background-color: var(--canvas);
}

.geometric-accents span {
    position: absolute;
    opacity: 0;
    animation: accentFadeIn 0.4s ease forwards;
}

.accent-circle {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--signal-red);
}

.accent-circle:nth-child(2) {
    background-color: var(--depth-blue);
    animation-delay: 0.1s;
}

.accent-circle:nth-child(3) {
    background-color: var(--measure-gold);
    animation-delay: 0.2s;
}

.accent-square {
    width: 6px;
    height: 6px;
    background-color: var(--depth-blue);
    animation-delay: 0.3s;
}

.accent-square:nth-child(5) {
    background-color: var(--measure-gold);
    animation-delay: 0.4s;
}

@keyframes accentFadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Isometric Cube */
.iso-cube {
    width: 200px;
    height: 200px;
    position: relative;
    transform-style: preserve-3d;
    animation: cubeRotate 20s linear infinite;
}

.cube-face {
    position: absolute;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 700;
    font-size: clamp(2rem, 4vw, 3.4rem);
    border: 1px solid;
}

.cube-top {
    width: 200px;
    height: 200px;
    background: rgba(212, 40, 40, 0.05);
    border-color: var(--signal-red);
    transform: rotateX(60deg) translateZ(100px);
    color: var(--signal-red);
    opacity: 0;
    animation: faceDraw 0.6s ease 0s forwards;
}

.cube-front {
    width: 200px;
    height: 200px;
    background: rgba(40, 72, 168, 0.05);
    border-color: var(--depth-blue);
    transform: rotateY(0deg) translateZ(100px);
    color: var(--depth-blue);
    opacity: 0;
    animation: faceDraw 0.6s ease 0.3s forwards;
}

.cube-right {
    width: 200px;
    height: 200px;
    background: rgba(232, 200, 40, 0.05);
    border-color: var(--measure-gold);
    transform: rotateY(90deg) translateZ(100px);
    color: var(--measure-gold);
    opacity: 0;
    animation: faceDraw 0.6s ease 0.6s forwards;
}

@keyframes cubeRotate {
    from { transform: rotateX(-15deg) rotateY(0deg); }
    to { transform: rotateX(-15deg) rotateY(360deg); }
}

@keyframes faceDraw {
    from { opacity: 0; }
    to { opacity: 1; }
}

.iso-cube:hover {
    animation-duration: 10s;
}

.iso-cube:hover .cube-face {
    background: rgba(0, 0, 0, 0.15);
}

.vertex-line {
    position: absolute;
    bottom: 5vh;
    left: 50%;
    width: 1px;
    height: 0;
    background-color: var(--perspective);
    animation: lineGrow 0.8s ease 1s forwards;
}

@keyframes lineGrow {
    to { height: 10vh; }
}

/* Section 2: Comparison Engine */
#comparison-engine {
    min-height: 150vh;
    padding: 10vh 5vw;
    position: relative;
}

.convergence-lines {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
}

.observer-columns {
    display: flex;
    gap: 4vw;
    max-width: 1100px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
}

.observer-col {
    flex: 1;
    opacity: 0;
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.observer-a {
    transform: translateX(-60px) skewY(calc(var(--skew-angle) * -1));
}

.observer-a.visible {
    opacity: 1;
    transform: translateX(0) skewY(calc(var(--skew-angle) * -1));
}

.observer-b {
    transform: translateX(60px) skewY(var(--skew-angle));
}

.observer-b.visible {
    opacity: 1;
    transform: translateX(0) skewY(var(--skew-angle));
}

.observer-a .obs-para,
.observer-b .obs-para {
    transform: skewY(0);
}

.observer-label {
    font-size: clamp(1.5rem, 3vw, 2rem);
    margin-bottom: 2rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid;
}

.observer-a .observer-label {
    color: var(--signal-red);
    border-color: var(--signal-red);
}

.observer-b .observer-label {
    color: var(--viewpoint);
    border-color: var(--viewpoint);
}

.obs-para {
    margin-bottom: 3rem;
}

.obs-para h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--depth-blue);
}

.observer-b .obs-para h3 {
    color: var(--viewpoint);
}

/* Section 3: Scale Ladder */
#scale-ladder {
    min-height: 100vh;
    padding: 10vh 5vw;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.scale-block {
    padding: 2rem 2.5rem;
    overflow: hidden;
    opacity: 0;
    transition: opacity 0.5s ease, width 0.5s ease-out;
    width: 0;
}

.scale-block.visible {
    opacity: 1;
}

.block-1 {
    background-color: var(--signal-red);
    color: #fff;
    max-width: 20vw;
}

.block-1.visible { width: 20vw; }

.block-2 {
    background-color: var(--measure-gold);
    color: var(--frame);
    max-width: 35vw;
}

.block-2.visible { width: 35vw; }

.block-3 {
    background-color: var(--depth-blue);
    color: #fff;
    max-width: 50vw;
}

.block-3.visible { width: 50vw; }

.block-4 {
    background-color: var(--horizon);
    color: var(--frame);
    max-width: 70vw;
}

.block-4.visible { width: 70vw; }

.block-5 {
    background-color: var(--frame);
    color: #fff;
    max-width: 90vw;
}

.block-5.visible { width: 90vw; }

.scale-block h3 {
    font-size: clamp(1.3rem, 2vw, 1.8rem);
    margin-bottom: 0.5rem;
}

.scale-label {
    display: block;
    margin-bottom: 0.5rem;
    opacity: 0.7;
}

.scale-block p {
    margin-top: 0.5rem;
    line-height: 1.7;
}

/* Section 4: Final Frame */
#final-frame {
    height: 70vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background-color: var(--canvas);
}

.frame-border {
    position: absolute;
    top: 5vw;
    left: 5vw;
    right: 5vw;
    bottom: 5vw;
    border: 1px solid var(--frame);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 1s ease, border-width 0.5s ease;
}

.frame-border.visible {
    opacity: 1;
}

.frame-text {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
    color: var(--perspective);
    text-align: center;
    max-width: 40ch;
    opacity: 0;
    transition: opacity 0.6s ease 0.8s;
}

.frame-border.visible .frame-text {
    opacity: 1;
}

/* Responsive */
@media (max-width: 768px) {
    .observer-columns {
        flex-direction: column;
        gap: 4vh;
    }

    .observer-a,
    .observer-b {
        transform: none;
    }

    .observer-a.visible,
    .observer-b.visible {
        transform: none;
    }

    .scale-block {
        min-width: 80vw;
    }

    .block-1.visible, .block-2.visible, .block-3.visible,
    .block-4.visible, .block-5.visible {
        width: 90vw;
    }

    .iso-cube {
        width: 140px;
        height: 140px;
    }

    .cube-face {
        width: 140px;
        height: 140px;
        font-size: 1.5rem;
    }

    .cube-top { transform: rotateX(60deg) translateZ(70px); }
    .cube-front { transform: rotateY(0deg) translateZ(70px); }
    .cube-right { transform: rotateY(90deg) translateZ(70px); }
}

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

    .iso-cube {
        animation: none;
        transform: rotateX(-15deg) rotateY(45deg);
    }

    .cube-face,
    .geometric-accents span,
    .observer-col,
    .scale-block,
    .frame-border,
    .frame-text {
        opacity: 1 !important;
    }

    .observer-a, .observer-b {
        transform: none !important;
    }

    :root {
        --skew-angle: 0deg;
    }
}