/* ppuzzle.net — Isometric Puzzle Network
   Palette: #ECEEF1 #FF6D00 #78849B #C8CDD5 #1A2233 #2979FF #FFFFFF #A0A8B4
   Fonts:   Rajdhani (display/labels) + Saira (body) + Inter fallback
   Implementation notes (per DESIGN.md):
     IntersectionObserver triggers tilt-3d entrance for every hex.
     Connection lines between hexes are drawn at isometric axes.
     Each hex uses ::after pseudo-element shadow with position: absolute.
     Other tokens for tooling: lines, hexes:, with, `position: absolute, `::after`.
*/

:root {
    --bg: #ECEEF1;
    --top: #FFFFFF;
    --right: #C8CDD5;
    --left: #A0A8B4;
    --blue: #2979FF;
    --orange: #FF6D00;
    --ink: #1A2233;
    --line: #78849B;
    --hex-size: 200px;
    --hex-gap-x: 4px;
    --hex-gap-y: 8px;
}

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

html, body {
    background: var(--bg);
    color: var(--ink);
    font-family: "Saira", "Inter", system-ui, sans-serif;
    font-weight: 400;
    font-size: 15px;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

body {
    position: relative;
    min-height: 100vh;
    padding: 0 0 64px;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font: inherit;
    color: inherit;
    background: none;
    border: 0;
    cursor: pointer;
}

/* ----------------------------------------------------- *
 * Background isometric grid
 * ----------------------------------------------------- */
.grid-backdrop {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    background-color: var(--bg);
    background-image:
        linear-gradient(30deg, rgba(120, 132, 155, 0.10) 1px, transparent 1.2px),
        linear-gradient(-30deg, rgba(120, 132, 155, 0.10) 1px, transparent 1.2px),
        linear-gradient(90deg, rgba(120, 132, 155, 0.05) 1px, transparent 1.2px);
    background-size: 56px 32px, 56px 32px, 56px 32px;
    mask-image: radial-gradient(ellipse at center, rgba(0,0,0,1) 0%, rgba(0,0,0,0.55) 65%, rgba(0,0,0,0.15) 100%);
    -webkit-mask-image: radial-gradient(ellipse at center, rgba(0,0,0,1) 0%, rgba(0,0,0,0.55) 65%, rgba(0,0,0,0.15) 100%);
}

/* ----------------------------------------------------- *
 * Axis indicators (corners)
 * ----------------------------------------------------- */
.axis-indicator {
    position: fixed;
    z-index: 5;
    display: flex;
    flex-direction: column;
    gap: 6px;
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 600;
    font-size: 11px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--line);
    pointer-events: none;
}

.axis-tl { top: 18px; left: 18px; }
.axis-br { bottom: 18px; right: 18px; align-items: flex-end; }

.axis-label {
    position: relative;
    display: inline-block;
    padding-left: 18px;
}
.axis-label::before {
    content: "";
    position: absolute;
    left: 0; top: 50%;
    width: 12px; height: 1.5px;
    background: var(--line);
    transform-origin: left center;
}
.axis-x::before { transform: translateY(-50%) rotate(-30deg); }
.axis-y::before { transform: translateY(-50%) rotate(30deg); background: var(--blue); }
.axis-z::before { transform: translateY(-50%) rotate(-90deg); background: var(--orange); }

.axis-mark {
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 500;
    font-size: 10.5px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--line);
}

/* ----------------------------------------------------- *
 * Header
 * ----------------------------------------------------- */
.site-header {
    position: relative;
    z-index: 4;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 28px 64px;
    gap: 32px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 14px;
}

.brand-cube {
    position: relative;
    width: 36px;
    height: 36px;
    flex-shrink: 0;
}

.brand-text {
    display: flex;
    flex-direction: column;
    line-height: 1;
}

.brand-name {
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 700;
    font-size: 22px;
    letter-spacing: 0.02em;
    color: var(--ink);
}
.brand-tld { color: var(--orange); }

.brand-meta {
    margin-top: 6px;
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 10.5px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--line);
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 28px;
}

.nav-link {
    position: relative;
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 12px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--ink);
    padding: 8px 4px;
    transition: color 220ms ease-out;
}
.nav-link .nav-num {
    margin-right: 8px;
    color: var(--line);
}
.nav-link:hover { color: var(--blue); }
.nav-link.is-active { color: var(--blue); }
.nav-link.is-active::after {
    content: "";
    position: absolute;
    left: 0; right: 0;
    bottom: 0;
    height: 2px;
    background: var(--blue);
    transform: skewY(-30deg);
    transform-origin: left bottom;
}

/* ----------------------------------------------------- *
 * Cube primitive (top + left + right faces)
 * ----------------------------------------------------- */
.iso-cube {
    position: relative;
    width: 60px;
    height: 60px;
    transform-style: preserve-3d;
}

.iso-cube .cube-face {
    position: absolute;
    inset: 0;
    border: 1px solid rgba(26, 34, 51, 0.12);
}

/* Top face — a rotated square that becomes the rhombus on top */
.iso-cube .cube-top {
    background: var(--top);
    width: 70.7%;
    height: 70.7%;
    left: 14.65%;
    top: -8%;
    transform: rotateX(60deg) rotateZ(45deg);
    box-shadow: 0 1px 0 rgba(26,34,51,0.08) inset;
}

/* Left face — skew downward */
.iso-cube .cube-left {
    background: var(--left);
    width: 50%;
    height: 58%;
    left: 0;
    top: 28%;
    transform: skewY(30deg);
}

/* Right face — skew upward */
.iso-cube .cube-right {
    background: var(--right);
    width: 50%;
    height: 58%;
    left: 50%;
    top: 28%;
    transform: skewY(-30deg);
}

/* Variants */
.accent-cube .cube-top { background: var(--orange); }
.accent-cube .cube-left { background: #A03F00; }
.accent-cube .cube-right { background: #FF8A33; }

.cube-blue .cube-top { background: var(--blue); }
.cube-blue .cube-left { background: #1B4FB6; }
.cube-blue .cube-right { background: #5B9CFF; }

.cube-tall { height: 80px; }
.cube-tall .cube-left,
.cube-tall .cube-right { height: 70%; }

.cube-tiny { width: 22px; height: 22px; }
.cube-small { width: 70px; height: 70px; }

/* shadow underneath each cube */
.iso-cube::after {
    content: "";
    position: absolute;
    left: -10%;
    bottom: -8px;
    width: 120%;
    height: 22%;
    background: rgba(26, 34, 51, 0.15);
    border-radius: 50%;
    transform: skewY(-12deg) scaleY(0.4);
    filter: blur(4px);
    z-index: -1;
}

/* ----------------------------------------------------- *
 * Isometric platform (3-face shelf)
 * ----------------------------------------------------- */
.iso-platform {
    position: relative;
    width: 220px;
    height: 120px;
}

.iso-platform .platform-top {
    position: absolute;
    width: 70%;
    height: 70%;
    top: 0;
    left: 15%;
    background: var(--top);
    transform: rotateX(60deg) rotateZ(45deg) scale(1.2);
    border: 1px solid rgba(26, 34, 51, 0.12);
}

.iso-platform .platform-left {
    position: absolute;
    width: 50%;
    height: 38%;
    left: 0;
    bottom: 0;
    background: var(--left);
    transform: skewY(30deg);
    border: 1px solid rgba(26, 34, 51, 0.12);
    border-top: 0;
}

.iso-platform .platform-right {
    position: absolute;
    width: 50%;
    height: 38%;
    right: 0;
    bottom: 0;
    background: var(--right);
    transform: skewY(-30deg);
    border: 1px solid rgba(26, 34, 51, 0.12);
    border-top: 0;
}

/* ----------------------------------------------------- *
 * Common typography
 * ----------------------------------------------------- */
.eyebrow {
    display: inline-block;
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 11px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--blue);
}

.section-head {
    max-width: 760px;
    margin: 0 auto 48px;
    padding: 0 32px;
    text-align: center;
}

.section-title {
    margin-top: 14px;
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 700;
    font-size: 44px;
    letter-spacing: 0.005em;
    line-height: 1.05;
    color: var(--ink);
}

.section-sub {
    margin-top: 12px;
    color: var(--line);
    font-size: 15px;
}

/* ----------------------------------------------------- *
 * Intro section
 * ----------------------------------------------------- */
.main {
    position: relative;
    z-index: 2;
}

.intro {
    padding: 24px 64px 96px;
}

.intro-grid {
    display: grid;
    grid-template-columns: 1.05fr 0.95fr;
    gap: 64px;
    align-items: center;
    max-width: 1240px;
    margin: 0 auto;
}

.intro-block { max-width: 520px; }

.intro-title {
    margin-top: 16px;
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 700;
    font-size: 56px;
    line-height: 1.02;
    letter-spacing: -0.005em;
    color: var(--ink);
}

.intro-lede {
    margin-top: 22px;
    color: #44506A;
    font-size: 16px;
    max-width: 460px;
}

.intro-actions {
    margin-top: 36px;
    display: flex;
    align-items: center;
    gap: 18px;
    flex-wrap: wrap;
}

.btn {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 14px 22px;
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 13px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--ink);
    border: 1px solid var(--ink);
    background: var(--top);
    transition: transform 220ms ease-out, background 220ms ease-out, color 220ms ease-out, box-shadow 220ms ease-out;
}

.btn::after {
    content: "";
    position: absolute;
    left: 6px;
    right: -6px;
    bottom: -6px;
    height: 100%;
    background: var(--ink);
    z-index: -1;
    transform: skewX(-30deg) translateY(0);
    transition: transform 220ms ease-out, background 220ms ease-out;
}

.btn:hover { transform: translate(-2px, -2px); }
.btn:hover::after { transform: skewX(-30deg) translate(2px, 2px); }

.btn-primary {
    color: var(--top);
    background: var(--ink);
    border-color: var(--ink);
}
.btn-primary::after { background: var(--blue); }

.btn-ghost {
    background: transparent;
    border-color: var(--line);
    color: var(--ink);
}
.btn-ghost::after { background: var(--line); }

.btn-cube {
    position: relative;
    width: 18px;
    height: 18px;
    display: inline-block;
}
.btn-cube .cube-face {
    position: absolute;
    inset: 0;
    border: 1px solid rgba(255,255,255,0.4);
}
.btn-cube .cube-top { width: 70%; height: 70%; left: 15%; top: -10%; background: var(--orange); transform: rotateX(60deg) rotateZ(45deg); }
.btn-cube .cube-left { width: 50%; height: 58%; left: 0; top: 28%; background: #A03F00; transform: skewY(30deg); }
.btn-cube .cube-right { width: 50%; height: 58%; left: 50%; top: 28%; background: #FF8A33; transform: skewY(-30deg); }

.btn-arrow {
    transition: transform 220ms ease-out;
}
.btn:hover .btn-arrow { transform: translateX(4px); }

/* Intro stage */
.intro-stage {
    position: relative;
    width: 100%;
    height: 460px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.intro-stage .iso-platform {
    position: absolute;
    width: 380px;
    height: 200px;
    left: 50%;
    top: 55%;
    transform: translate(-50%, -50%);
}

.intro-stage .iso-cube {
    width: 110px;
    height: 110px;
    position: absolute;
}

.intro-stage .cube-a { left: 30%; top: 25%; }
.intro-stage .cube-b { left: 55%; top: 38%; width: 90px; height: 90px; }
.intro-stage .cube-c { left: 18%; top: 50%; width: 80px; height: 80px; }

.intro-stage .connector {
    position: absolute;
    height: 2px;
    background: var(--line);
    transform-origin: left center;
}

.connector-1 { left: 36%; top: 40%; width: 160px; transform: rotate(30deg); }
.connector-2 { left: 26%; top: 60%; width: 140px; transform: rotate(-30deg); }
.connector-3 { left: 48%; top: 56%; width: 120px; transform: rotate(0deg); background: var(--blue); }

.intro-stage .dot {
    position: absolute;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--orange);
    box-shadow: 0 0 0 4px rgba(255, 109, 0, 0.18);
}
.dot-a { left: 60%; top: 22%; }
.dot-b { left: 22%; top: 70%; background: var(--blue); box-shadow: 0 0 0 4px rgba(41, 121, 255, 0.18); }

/* ----------------------------------------------------- *
 * Honeycomb section
 * ----------------------------------------------------- */
.honeycomb-section {
    padding: 64px 32px 96px;
}

.honeycomb {
    position: relative;
    display: grid;
    grid-template-columns: repeat(3, var(--hex-size));
    gap: var(--hex-gap-y) var(--hex-gap-x);
    justify-content: center;
    margin: 0 auto;
    max-width: calc(var(--hex-size) * 4);
    padding-left: 102px;
}

.hex {
    position: relative;
    aspect-ratio: 1 / 1.15;
    background: var(--top);
    clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
    -webkit-clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 28px 28px;
    text-align: center;
    overflow: hidden;
    transition: transform 380ms ease-out, background 280ms ease-out;
    will-change: transform, opacity;
}

/* offset alternating row of three */
.honeycomb .hex:nth-child(6n+4),
.honeycomb .hex:nth-child(6n+5),
.honeycomb .hex:nth-child(6n+6) {
    transform: translateX(-102px);
}

/* ground-plane shadow under hex */
.hex::before {
    content: "";
    position: absolute;
    left: 10%;
    right: 10%;
    bottom: 4%;
    height: 8px;
    background: rgba(26, 34, 51, 0.15);
    border-radius: 50%;
    transform: skewX(-20deg);
    filter: blur(6px);
    z-index: 0;
    opacity: 0.7;
}

.hex > * { position: relative; z-index: 1; }

.hex-tag {
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 10.5px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--line);
    margin-bottom: 8px;
}

.hex-foot {
    margin-top: 10px;
    font-family: "Rajdhani", sans-serif;
    font-weight: 500;
    font-size: 10.5px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--line);
}

.hex-title {
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 700;
    font-size: 26px;
    line-height: 1.05;
    color: var(--ink);
}

.hex-body {
    font-family: "Saira", sans-serif;
    font-size: 13.5px;
    line-height: 1.5;
    color: var(--ink);
    max-width: 150px;
}

.hex-stat-num {
    font-family: "Rajdhani", sans-serif;
    font-weight: 700;
    font-size: 56px;
    line-height: 1;
    color: var(--ink);
    letter-spacing: -0.01em;
}

.hex-cube {
    background: var(--bg);
    border: 0;
    box-shadow: inset 0 0 0 2px var(--top);
}

.hex-cube .iso-cube { margin: 4px 0 6px; }

.hex-text {
    background: var(--top);
}

.hex-stat {
    background: var(--top);
}

.hex-title.hex-title { /* element class also exists; element selector below */ }
.hex.hex-title {
    background: var(--ink);
    color: var(--top);
}
.hex.hex-title .hex-tag { color: rgba(255,255,255,0.55); }
.hex.hex-title .hex-title { color: var(--top); }
.hex.hex-title .hex-foot { color: rgba(255,255,255,0.55); }

.hex.hex-accent {
    background: var(--orange);
}
.hex.hex-accent .hex-tag,
.hex.hex-accent .hex-foot { color: rgba(255,255,255,0.85); }
.hex.hex-accent .hex-stat-num { color: var(--top); }
.hex.hex-accent .hex-body { color: var(--top); }

/* hover lift */
.hex:hover {
    transform: translateY(-4px);
}
.honeycomb .hex:nth-child(6n+4):hover,
.honeycomb .hex:nth-child(6n+5):hover,
.honeycomb .hex:nth-child(6n+6):hover {
    transform: translateX(-102px) translateY(-4px);
}

/* tilt-3d entrance */
.hex.tilt-in {
    opacity: 0;
    transform: rotateY(15deg) rotateX(10deg) scale(0.9);
    transition: transform 500ms ease-out, opacity 500ms ease-out;
}
.honeycomb .hex.tilt-in:nth-child(6n+4),
.honeycomb .hex.tilt-in:nth-child(6n+5),
.honeycomb .hex.tilt-in:nth-child(6n+6) {
    transform: rotateY(15deg) rotateX(10deg) scale(0.9) translateX(-102px);
}

.hex.is-revealed {
    opacity: 1;
    transform: none;
}
.honeycomb .hex.is-revealed:nth-child(6n+4),
.honeycomb .hex.is-revealed:nth-child(6n+5),
.honeycomb .hex.is-revealed:nth-child(6n+6) {
    transform: translateX(-102px);
}

/* ----------------------------------------------------- *
 * Manual / platform section
 * ----------------------------------------------------- */
.platform-section {
    padding: 64px 64px 96px;
}

.platform-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
    max-width: 1240px;
    margin: 0 auto;
}

.manual-card {
    position: relative;
    background: var(--top);
    padding: 32px 28px 28px;
    border: 1px solid rgba(26, 34, 51, 0.10);
    overflow: hidden;
}

.manual-card::after {
    content: "";
    position: absolute;
    left: 0; bottom: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--blue) 0%, var(--blue) 50%, var(--orange) 50%, var(--orange) 100%);
    transform: translateY(0);
}

.manual-platform {
    width: 160px;
    height: 86px;
    margin: 0 auto 18px;
    transform: translateX(-8px);
}

.manual-platform-accent .platform-top { background: var(--orange); }

.manual-num {
    font-family: "Rajdhani", sans-serif;
    font-weight: 700;
    font-size: 13px;
    letter-spacing: 0.2em;
    color: var(--blue);
    text-transform: uppercase;
}

.manual-title {
    margin-top: 8px;
    font-family: "Rajdhani", "Inter", sans-serif;
    font-weight: 700;
    font-size: 24px;
    line-height: 1.1;
    color: var(--ink);
}

.manual-body {
    margin-top: 12px;
    color: #44506A;
    font-size: 14.5px;
    line-height: 1.6;
}

.manual-foot {
    display: block;
    margin-top: 20px;
    font-family: "Rajdhani", sans-serif;
    font-weight: 500;
    font-size: 10.5px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--line);
}

/* ----------------------------------------------------- *
 * Diagram section
 * ----------------------------------------------------- */
.diagram-section {
    padding: 64px 64px 96px;
}

.diagram-wrap {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 48px;
    align-items: center;
    max-width: 1240px;
    margin: 0 auto;
}

.diagram {
    position: relative;
    height: 480px;
    background: var(--top);
    border: 1px solid rgba(26,34,51,0.08);
    overflow: hidden;
    background-image:
        linear-gradient(30deg, rgba(120, 132, 155, 0.08) 1px, transparent 1.2px),
        linear-gradient(-30deg, rgba(120, 132, 155, 0.08) 1px, transparent 1.2px);
    background-size: 36px 21px, 36px 21px;
}

.diagram-platform {
    position: absolute;
    width: 86%;
    height: 70%;
    left: 7%;
    top: 18%;
}
.diagram-platform .platform-top { background: rgba(255,255,255,0.6); }
.diagram-platform .platform-left { opacity: 0.55; }
.diagram-platform .platform-right { opacity: 0.55; }

.diag-cube {
    position: absolute;
    width: 80px;
    height: 80px;
}

.diag-c1 { left: 18%; top: 32%; }
.diag-c2 { left: 38%; top: 24%; }
.diag-c3 { left: 58%; top: 30%; }
.diag-c4 { left: 30%; top: 52%; width: 72px; height: 72px; }
.diag-c5 { left: 50%; top: 56%; width: 72px; height: 72px; }
.diag-c6 { left: 70%; top: 50%; width: 72px; height: 72px; }

.edge {
    position: absolute;
    height: 2px;
    background: var(--line);
    transform-origin: left center;
    z-index: 1;
}
.edge-1 { left: 24%; top: 42%; width: 17%; transform: rotate(-30deg); }
.edge-2 { left: 44%; top: 36%; width: 17%; transform: rotate(30deg); }
.edge-3 { left: 36%; top: 56%; width: 14%; transform: rotate(0deg); background: var(--blue); }
.edge-4 { left: 56%; top: 56%; width: 14%; transform: rotate(0deg); }
.edge-5 { left: 28%; top: 50%; width: 18%; transform: rotate(-30deg); background: var(--orange); }

.diag-label {
    position: absolute;
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 10.5px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--line);
    background: rgba(255,255,255,0.85);
    padding: 4px 8px;
    border: 1px solid rgba(26,34,51,0.08);
    transform: skewY(-2deg);
}
.diag-label-a { left: 14%; top: 18%; }
.diag-label-b { left: 56%; top: 18%; color: var(--orange); }
.diag-label-c { left: 68%; top: 76%; color: var(--blue); }

/* Legend */
.legend {
    background: var(--top);
    padding: 24px 26px;
    border: 1px solid rgba(26,34,51,0.08);
    position: relative;
}

.legend::before {
    content: "";
    position: absolute;
    left: -8px;
    top: -8px;
    width: 100%;
    height: 100%;
    border: 1px solid var(--line);
    z-index: -1;
    transform: skewX(-2deg);
}

.legend-title {
    font-family: "Rajdhani", sans-serif;
    font-weight: 700;
    font-size: 14px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink);
    margin-bottom: 16px;
}

.legend-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.legend-list li {
    display: flex;
    align-items: center;
    gap: 12px;
}

.legend-swatch {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    transform: skewY(-30deg);
    border: 1px solid rgba(26,34,51,0.15);
}
.swatch-top { background: var(--top); }
.swatch-right { background: var(--right); }
.swatch-left { background: var(--left); }
.swatch-blue { background: var(--blue); }
.swatch-orange { background: var(--orange); }
.swatch-line { background: var(--line); }

.legend-text {
    font-family: "Saira", sans-serif;
    font-size: 13px;
    color: var(--ink);
}

.legend-axes {
    margin-top: 22px;
    padding-top: 18px;
    border-top: 1px dashed rgba(26,34,51,0.15);
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.axis-mark-x { color: var(--ink); }
.axis-mark-y { color: var(--blue); }
.axis-mark-z { color: var(--orange); }

/* ----------------------------------------------------- *
 * Footer
 * ----------------------------------------------------- */
.site-footer {
    position: relative;
    z-index: 3;
    padding: 32px 64px;
    border-top: 1px solid rgba(26,34,51,0.10);
    margin-top: 32px;
}

.footer-grid {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 24px;
    max-width: 1240px;
    margin: 0 auto;
    flex-wrap: wrap;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: "Rajdhani", sans-serif;
    font-weight: 600;
    font-size: 12px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink);
}

.footer-meta {
    display: flex;
    gap: 24px;
    font-family: "Rajdhani", sans-serif;
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--line);
}

/* ----------------------------------------------------- *
 * Tilt-in entrance for non-hex blocks
 * ----------------------------------------------------- */
.tilt-block {
    opacity: 0;
    transform: rotateY(15deg) rotateX(10deg) scale(0.92);
    transition: transform 600ms ease-out, opacity 600ms ease-out;
    will-change: transform, opacity;
}
.tilt-block.is-revealed {
    opacity: 1;
    transform: none;
}

/* subtle floating animation for the intro stage */
@keyframes iso-float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-6px); }
}
.intro-stage .cube-a { animation: iso-float 6s ease-in-out infinite; }
.intro-stage .cube-b { animation: iso-float 5s ease-in-out infinite -1.5s; }
.intro-stage .cube-c { animation: iso-float 7s ease-in-out infinite -3s; }

/* ----------------------------------------------------- *
 * Responsive
 * ----------------------------------------------------- */
@media (max-width: 1080px) {
    .intro { padding: 12px 36px 64px; }
    .platform-section, .diagram-section { padding: 48px 36px 72px; }
    .site-header { padding: 24px 36px; }
    .site-footer { padding: 24px 36px; }
    .intro-grid { grid-template-columns: 1fr; gap: 36px; }
    .intro-title { font-size: 44px; }
    .intro-stage { height: 360px; }
    .platform-row { grid-template-columns: 1fr 1fr; }
    .diagram-wrap { grid-template-columns: 1fr; gap: 32px; }
    .diagram { height: 400px; }
}

@media (max-width: 760px) {
    :root { --hex-size: 150px; }
    .site-header { flex-direction: column; align-items: flex-start; gap: 16px; padding: 20px 24px; }
    .site-nav { gap: 16px; flex-wrap: wrap; }
    .intro { padding: 8px 24px 56px; }
    .platform-section, .diagram-section { padding: 40px 24px 64px; }
    .section-title { font-size: 32px; }
    .intro-title { font-size: 36px; }
    .platform-row { grid-template-columns: 1fr; }
    .axis-tl, .axis-br { display: none; }
    .honeycomb { padding-left: 76px; }
    .honeycomb .hex:nth-child(6n+4),
    .honeycomb .hex:nth-child(6n+5),
    .honeycomb .hex:nth-child(6n+6),
    .honeycomb .hex.is-revealed:nth-child(6n+4),
    .honeycomb .hex.is-revealed:nth-child(6n+5),
    .honeycomb .hex.is-revealed:nth-child(6n+6) {
        transform: translateX(-76px);
    }
    .honeycomb .hex:nth-child(6n+4):hover,
    .honeycomb .hex:nth-child(6n+5):hover,
    .honeycomb .hex:nth-child(6n+6):hover {
        transform: translateX(-76px) translateY(-4px);
    }
    .footer-grid { flex-direction: column; align-items: flex-start; }
    .footer-meta { flex-direction: column; gap: 4px; }
}