/* ═══════════════════════════════════════════════════════════════
   WELLKON QAI — Modern Futuristic Design System
   Colors from logo: deep blue #2D35A8 → bright blue #3CB9F5 + white
═══════════════════════════════════════════════════════════════ */

:root {
    --bg:         #06060F;
    --bg2:        #0A0A18;
    --blue-deep:  #2D35A8;
    --blue-mid:   #3A5ADC;
    --blue-light: #3CB9F5;
    --white:      #FFFFFF;
    --text:       #E8EAF6;
    --muted:      #7B82B0;
    --border:     rgba(60, 185, 245, 0.12);
    --glass:      rgba(255, 255, 255, 0.04);
    --glass-b:    rgba(60, 185, 245, 0.15);
    --grad:       linear-gradient(135deg, var(--blue-mid) 0%, var(--blue-light) 100%);
    --glow:       0 0 40px rgba(60, 185, 245, 0.3);
    --glow-sm:    0 0 20px rgba(60, 185, 245, 0.2);
    --radius:     16px;
    --radius-sm:  10px;
    --font:       'Inter', -apple-system, sans-serif;
    --mono:       'JetBrains Mono', monospace;
    --nav-h:      72px;
    --container:  min(1280px, calc(100vw - 2rem));
}

/* ── Reset ───────────────────────────────────────────────────── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--nav-h); }
body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.65;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a  { color: inherit; text-decoration: none; }

/* ── Neural network canvas ───────────────────────────────────── */
#neural-network {
    position: fixed; inset: 0;
    z-index: -1;
    pointer-events: none;
}

/* Background gradient behind canvas */
body::before {
    content: '';
    position: fixed; inset: 0;
    background:
        radial-gradient(ellipse 60% 50% at 10% 20%, rgba(45, 53, 168, 0.25) 0%, transparent 60%),
        radial-gradient(ellipse 50% 60% at 90% 80%, rgba(60, 185, 245, 0.15) 0%, transparent 60%),
        linear-gradient(180deg, #06060F 0%, #080812 100%);
    z-index: -2;
    animation: bgPulse 20s ease-in-out infinite;
}
@keyframes bgPulse {
    0%,100% { opacity: 1; }
    50%      { opacity: 0.8; }
}

/* ── Utilities ───────────────────────────────────────────────── */
.container { width: var(--container); margin: 0 auto; padding: 0 1rem; }

.grad-text {
    background: var(--grad);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-label {
    display: inline-block;
    font-size: .75rem;
    font-weight: 600;
    letter-spacing: .12em;
    text-transform: uppercase;
    color: var(--blue-light);
    border: 1px solid rgba(60,185,245,.25);
    padding: .3rem .9rem;
    border-radius: 99px;
    margin-bottom: 1.1rem;
    background: rgba(60,185,245,.06);
}

.section-head {
    text-align: center;
    max-width: 640px;
    margin: 0 auto 4rem;
}
.section-head h2 { font-size: clamp(2rem, 4vw, 2.8rem); font-weight: 800; margin-bottom: .8rem; }
.section-head p  { color: var(--muted); font-size: 1.05rem; }

/* fade-in animation */
.fade-in { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.fade-in.visible { opacity: 1; transform: none; }

/* ── Buttons ─────────────────────────────────────────────────── */
.btn-primary, .btn-ghost {
    display: inline-flex; align-items: center; gap: .5rem;
    font-size: .95rem; font-weight: 600;
    padding: .75rem 1.6rem;
    border-radius: 99px;
    transition: transform .2s, box-shadow .2s, background .2s;
    cursor: pointer; border: none;
    white-space: nowrap;
}
.btn-primary {
    background: var(--grad);
    color: #fff;
    box-shadow: 0 4px 24px rgba(58, 90, 220, .4);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(58, 90, 220, .55); }

.btn-ghost {
    background: transparent;
    color: var(--blue-light);
    border: 1.5px solid rgba(60,185,245,.35);
}
.btn-ghost:hover { background: rgba(60,185,245,.08); transform: translateY(-2px); border-color: var(--blue-light); }

.btn-lg { padding: .9rem 2rem; font-size: 1rem; }

/* ── Header / Nav ────────────────────────────────────────────── */
.header {
    position: fixed; top: 0; left: 0; right: 0;
    height: var(--nav-h);
    z-index: 1000;
    transition: background .3s, box-shadow .3s;
}
.header.scrolled {
    background: rgba(6, 6, 15, .88);
    backdrop-filter: blur(8px);
    box-shadow: 0 1px 0 var(--border);
}

.nav {
    display: flex;
    align-items: center;
    height: var(--nav-h);
    gap: 2rem;
}

.logo {
    display: flex; align-items: center; gap: .7rem;
    font-size: 1.1rem; font-weight: 700;
    flex-shrink: 0;
    color: var(--white);
}
.logo span { color: var(--blue-light); }

/* Mini atom logo */
.logo-atom {
    position: relative; width: 32px; height: 32px; flex-shrink: 0;
}
.la-ring {
    position: absolute; inset: 0;
    border-radius: 50%;
    border: 1.5px solid transparent;
}
.la-r1 {
    border-color: var(--blue-mid) transparent;
    animation: laR1 2.2s linear infinite;
}
.la-r2 {
    border-color: transparent var(--blue-light);
    transform: rotate(60deg);
    animation: laR2 3s linear infinite;
}
@keyframes laR1 { to { transform: rotate(360deg); } }
@keyframes laR2 { to { transform: rotate(420deg); } }
.la-dot {
    position: absolute; width: 5px; height: 5px;
    border-radius: 50%; background: var(--blue-light);
}
.la-d1 { top: 0; left: 50%; transform: translateX(-50%); }
.la-d2 { bottom: 0; left: 50%; transform: translateX(-50%); }
.la-core {
    position: absolute; inset: 8px;
    border-radius: 50%;
    background: radial-gradient(circle, var(--blue-light), var(--blue-deep));
    box-shadow: 0 0 10px var(--blue-light);
}

.nav-menu {
    display: flex; list-style: none; gap: .25rem;
    margin-left: auto;
}
.nav-link {
    display: block; padding: .5rem .85rem;
    font-size: .9rem; font-weight: 500; color: var(--muted);
    border-radius: 8px;
    transition: color .2s, background .2s;
}
.nav-link:hover { color: var(--white); background: rgba(255,255,255,.06); }

.nav-right { display: flex; align-items: center; gap: .75rem; flex-shrink: 0; }

.lang-btn {
    display: flex; align-items: center; gap: .4rem;
    background: none; border: 1px solid var(--border);
    color: var(--muted); font: inherit; font-size: .85rem;
    padding: .4rem .75rem; border-radius: 99px; cursor: pointer;
    transition: color .2s, border-color .2s;
}
.lang-btn:hover { color: var(--blue-light); border-color: var(--blue-light); }

.hamburger {
    display: none; flex-direction: column; gap: 5px;
    background: none; border: none; cursor: pointer; padding: .5rem;
}
.hamburger span {
    display: block; width: 22px; height: 2px;
    background: var(--text); border-radius: 2px;
    transition: transform .3s, opacity .3s;
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Mobile nav overlay */
.nav-overlay {
    display: none; position: fixed; inset: 0;
    background: rgba(0,0,0,.6); z-index: 998;
    backdrop-filter: blur(4px);
}
.nav-overlay.active { display: block; }

/* ── Hero ────────────────────────────────────────────────────── */
.hero {
    min-height: 100vh;
    padding: calc(var(--nav-h) + 5rem) 0 5rem;
    display: flex; align-items: center;
    position: relative;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 4rem;
}

/* pill badge */
.pill-badge {
    display: inline-flex; align-items: center; gap: .5rem;
    font-size: .78rem; font-weight: 600; letter-spacing: .08em; text-transform: uppercase;
    color: var(--blue-light);
    background: rgba(60,185,245,.08);
    border: 1px solid rgba(60,185,245,.25);
    padding: .35rem 1rem; border-radius: 99px;
    margin-bottom: 1.5rem;
}
.pill-dot {
    width: 7px; height: 7px; border-radius: 50%;
    background: var(--blue-light);
    box-shadow: 0 0 8px var(--blue-light);
    animation: blink 1.6s ease-in-out infinite;
}
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:.3} }

.hero-content h1 {
    font-size: clamp(3rem, 6vw, 5rem);
    font-weight: 900;
    line-height: 1.05;
    color: var(--white);
    margin-bottom: 1.5rem;
}
.hero-sub {
    font-size: 1.05rem;
    color: var(--muted);
    line-height: 1.7;
    max-width: 480px;
    margin-bottom: 2rem;
    font-style: italic;
}
.hero-actions { display: flex; gap: 1rem; flex-wrap: wrap; margin-bottom: 3rem; }

.hero-metrics {
    display: flex; align-items: center; gap: 1.5rem;
}
.metric { display: flex; flex-direction: column; }
.metric strong { font-size: 1.5rem; font-weight: 800; color: var(--white); line-height: 1; }
.metric span   { font-size: .72rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin-top: .2rem; }
.metric-sep    { width: 1px; height: 36px; background: var(--border); }

/* ── Quantum Sphere Visual ───────────────────────────────────── */
.hero-visual { display: flex; justify-content: center; align-items: center; }

.qviz {
    position: relative;
    width: 420px; height: 420px;
    display: flex; align-items: center; justify-content: center;
}

.qv-glow {
    position: absolute; inset: -40px;
    background: radial-gradient(circle, rgba(58,90,220,.25) 0%, transparent 70%);
    animation: qGlowPulse 4s ease-in-out infinite;
}
@keyframes qGlowPulse { 0%,100%{opacity:.6} 50%{opacity:1} }

.qv-sphere {
    position: absolute; inset: 60px;
    display: flex; align-items: center; justify-content: center;
}

.qv-ring {
    position: absolute; inset: 0;
    border-radius: 50%;
    border: 1.5px solid transparent;
}
.qv-r1 { border-color: rgba(60,185,245,.7) transparent; animation: qr1 4s linear infinite; }
.qv-r2 { border-color: transparent rgba(58,90,220,.7); transform: rotate(60deg); animation: qr2 6s linear infinite; }
.qv-r3 { border-color: rgba(60,185,245,.4) transparent; transform: rotate(-30deg) scaleX(.7); animation: qr3 5s linear infinite reverse; }
@keyframes qr1 { to{transform: rotate(360deg)} }
@keyframes qr2 { to{transform: rotate(420deg)} }
@keyframes qr3 { to{transform: rotate(-390deg) scaleX(.7)} }

.qv-electron {
    position: absolute; top: -5px; left: 50%; transform: translateX(-50%);
    width: 10px; height: 10px; border-radius: 50%;
    background: var(--blue-light);
    box-shadow: 0 0 12px var(--blue-light), 0 0 24px rgba(60,185,245,.5);
}

.qv-core {
    position: absolute; width: 80px; height: 80px;
    border-radius: 50%;
    background: radial-gradient(circle at 35% 35%, #7BB8FF, var(--blue-mid));
    box-shadow: 0 0 30px rgba(58,90,220,.8), 0 0 60px rgba(58,90,220,.4);
    display: flex; align-items: center; justify-content: center;
    z-index: 2;
}
.qv-core-inner {
    width: 40px; height: 40px; border-radius: 50%;
    background: radial-gradient(circle at 40% 40%, #FFFFFF, var(--blue-light));
    box-shadow: 0 0 20px #fff;
    animation: corePulse 2.5s ease-in-out infinite;
}
.qv-core-pulse {
    position: absolute; inset: -10px; border-radius: 50%;
    border: 2px solid rgba(60,185,245,.4);
    animation: ringExpand 2.5s ease-out infinite;
}
@keyframes corePulse { 0%,100%{transform:scale(1)} 50%{transform:scale(1.1)} }
@keyframes ringExpand { 0%{transform:scale(.8);opacity:1} 100%{transform:scale(1.8);opacity:0} }

.qv-circuit {
    position: absolute; inset: 0;
    display: flex; align-items: center; justify-content: center;
    opacity: .8;
}
.qv-circuit svg { width: 55%; height: 55%; }

.qv-hud {
    position: absolute; inset: 0; pointer-events: none;
}
.qv-hud-corner {
    position: absolute; width: 20px; height: 20px;
}
.qv-hc-tl { top: 20px;  left: 20px;  border-top: 2px solid var(--blue-light); border-left: 2px solid var(--blue-light); }
.qv-hc-tr { top: 20px;  right: 20px; border-top: 2px solid var(--blue-light); border-right: 2px solid var(--blue-light); }
.qv-hc-bl { bottom: 20px; left: 20px;  border-bottom: 2px solid var(--blue-light); border-left: 2px solid var(--blue-light); }
.qv-hc-br { bottom: 20px; right: 20px; border-bottom: 2px solid var(--blue-light); border-right: 2px solid var(--blue-light); }

.qv-hud-line {
    position: absolute; background: rgba(60,185,245,.2);
}
.qv-hl1 { top: 50%; left: 0; right: 0; height: 1px; }
.qv-hl2 { left: 50%; top: 0; bottom: 0; width: 1px; }

/* Scroll hint */
.scroll-hint {
    position: absolute; bottom: 2.5rem; left: 50%; transform: translateX(-50%);
    display: flex; flex-direction: column; align-items: center; gap: .5rem;
}
.scroll-mouse {
    width: 22px; height: 36px; border: 2px solid rgba(60,185,245,.4);
    border-radius: 12px; display: flex; justify-content: center; padding-top: 6px;
}
.scroll-wheel {
    width: 3px; height: 8px; background: var(--blue-light);
    border-radius: 3px; animation: scrollWheel 1.8s ease-in-out infinite;
}
@keyframes scrollWheel { 0%{transform:translateY(0);opacity:1} 100%{transform:translateY(10px);opacity:0} }

/* ── About ───────────────────────────────────────────────────── */
.about {
    padding: 8rem 0;
    position: relative;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 5rem;
    align-items: center;
}

/* Holographic card */
.holo-card {
    position: relative;
    background: var(--glass);
    border: 1px solid var(--glass-b);
    border-radius: 24px;
    padding: 2.5rem;
    overflow: hidden;
    backdrop-filter: blur(8px);
    box-shadow: var(--glow);
}
.holo-glow {
    position: absolute; inset: -1px;
    border-radius: 24px;
    background: linear-gradient(135deg, rgba(58,90,220,.2), rgba(60,185,245,.1), rgba(58,90,220,.2));
    z-index: 0;
    animation: holoBorder 4s ease-in-out infinite;
}
@keyframes holoBorder { 0%,100%{opacity:.5} 50%{opacity:1} }

.holo-bg {
    position: absolute; inset: 0;
    background: radial-gradient(ellipse at 70% 30%, rgba(58,90,220,.12), transparent 60%);
}

.holo-rings {
    position: absolute; top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
}
.hr {
    position: absolute; border-radius: 50%;
    border: 1px solid rgba(60,185,245,.15);
    transform: translate(-50%, -50%);
}
.hr1 { width: 180px; height: 180px; top:0; left:0; }
.hr2 { width: 280px; height: 280px; top:0; left:0; }
.hr3 { width: 380px; height: 380px; top:0; left:0; }

.holo-icon {
    position: relative; z-index: 1;
    width: 64px; height: 64px;
    border-radius: 16px;
    background: var(--grad);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.6rem; color: #fff;
    box-shadow: 0 8px 24px rgba(58,90,220,.5);
    margin-bottom: 1.5rem;
}

/* Bloch Sphere */
.bloch-wrap {
    position: relative; z-index: 1;
    display: flex; flex-direction: column; align-items: flex-start;
    margin-bottom: 1.2rem;
}
.bloch-svg {
    width: 148px; height: 148px;
    overflow: visible;
    filter: drop-shadow(0 0 14px rgba(58,90,220,.5));
}
.bloch-label {
    font-family: var(--mono);
    font-size: .65rem;
    color: rgba(60,185,245,.65);
    text-transform: uppercase;
    letter-spacing: .12em;
    margin-top: .35rem;
}

.holo-data { position: relative; z-index: 1; margin-bottom: 1.5rem; }
.hd-row {
    display: flex; justify-content: space-between; align-items: center;
    padding: .55rem 0;
    border-bottom: 1px solid rgba(60,185,245,.08);
    font-family: var(--mono);
    font-size: .82rem;
}
.hd-key { color: var(--muted); text-transform: uppercase; letter-spacing: .08em; }
.hd-val { color: var(--white); font-weight: 600; }
.hd-online { color: #00E676; }

.holo-tags {
    position: relative; z-index: 1;
    display: flex; gap: .5rem; flex-wrap: wrap;
}
.holo-tags span {
    font-size: .72rem; font-weight: 600; text-transform: uppercase; letter-spacing: .08em;
    color: var(--blue-light);
    background: rgba(60,185,245,.1);
    border: 1px solid rgba(60,185,245,.2);
    padding: .25rem .65rem; border-radius: 99px;
}

.holo-scan {
    position: absolute; inset: 0;
    background: linear-gradient(180deg, transparent 0%, rgba(60,185,245,.06) 50%, transparent 100%);
    animation: scanLine 3s ease-in-out infinite;
    pointer-events: none;
    z-index: 2;
}
@keyframes scanLine {
    0%   { transform: translateY(-100%); }
    100% { transform: translateY(100%); }
}

.about-content h2 { font-size: clamp(2rem, 3.5vw, 2.6rem); font-weight: 800; margin-bottom: 1.2rem; }
.about-content p  { color: var(--muted); margin-bottom: 1rem; line-height: 1.7; }
.about-content .btn-primary { margin-top: .5rem; }

/* ── Research ────────────────────────────────────────────────── */
.research-section { padding: 8rem 0; }

.r-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.r-card {
    background: var(--glass);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: transform .3s, box-shadow .3s, border-color .3s;
}
.r-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--glow);
    border-color: rgba(60,185,245,.3);
}
.r-card-featured {
    border-color: rgba(58,90,220,.4);
    box-shadow: 0 0 30px rgba(58,90,220,.2);
}

/* Card top image area */
.r-card-img {
    position: relative; height: 180px;
    overflow: hidden;
    display: flex; align-items: center; justify-content: center;
}
.r-img-quantum { background: linear-gradient(135deg, #0D0D2E 0%, #1A1060 100%); }
.r-img-ai      { background: linear-gradient(135deg, #060820 0%, #0E1A50 100%); }
.r-img-vr      { background: linear-gradient(135deg, #080E28 0%, #142060 100%); }

.r-img-overlay {
    position: absolute; inset: 0;
    background: radial-gradient(circle at 50% 60%, rgba(60,185,245,.15) 0%, transparent 70%);
}

.r-img-icon {
    position: relative; z-index: 2;
    font-size: 3rem;
    color: var(--blue-light);
    filter: drop-shadow(0 0 16px var(--blue-light));
    animation: iconFloat 3s ease-in-out infinite;
}
@keyframes iconFloat { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-8px)} }

/* CSS futuristic patterns in card images */
.r-img-dots {
    position: absolute; inset: 0;
    background-image: radial-gradient(circle, rgba(60,185,245,.35) 1px, transparent 1px);
    background-size: 18px 18px;
    opacity: .5;
}
.r-img-nodes {
    position: absolute; inset: 0;
    background-image:
        radial-gradient(circle, rgba(60,185,245,.5) 1.5px, transparent 1.5px),
        linear-gradient(rgba(60,185,245,.08) 1px, transparent 1px),
        linear-gradient(90deg, rgba(60,185,245,.08) 1px, transparent 1px);
    background-size: 30px 30px, 30px 30px, 30px 30px;
    opacity: .6;
}
.r-img-grid {
    position: absolute; inset: 0;
    background-image:
        linear-gradient(rgba(60,185,245,.15) 1px, transparent 1px),
        linear-gradient(90deg, rgba(60,185,245,.15) 1px, transparent 1px);
    background-size: 24px 24px;
    transform: perspective(120px) rotateX(20deg);
    opacity: .7;
}

.r-card-body { padding: 1.6rem; }
.r-card-body h3 { font-size: 1.15rem; font-weight: 700; color: var(--white); margin-bottom: .7rem; }
.r-card-body p  { font-size: .9rem; color: var(--muted); line-height: 1.65; margin-bottom: 1.2rem; }

.r-tags { display: flex; gap: .4rem; flex-wrap: wrap; }
.r-tags span {
    font-size: .7rem; font-weight: 600; text-transform: uppercase; letter-spacing: .07em;
    color: var(--blue-light);
    background: rgba(60,185,245,.08);
    border: 1px solid rgba(60,185,245,.15);
    padding: .2rem .55rem; border-radius: 99px;
}

/* ── Differentials ───────────────────────────────────────────── */
.diff-section { padding: 8rem 0; }

.diff-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.diff-card {
    background: var(--glass);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2.5rem;
    transition: transform .3s, border-color .3s, box-shadow .3s;
}
.diff-card:hover {
    transform: translateY(-4px);
    border-color: rgba(60,185,245,.3);
    box-shadow: var(--glow-sm);
}
.diff-icon-wrap {
    width: 52px; height: 52px;
    border-radius: 14px;
    background: var(--grad);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.3rem; color: #fff;
    box-shadow: 0 6px 20px rgba(58,90,220,.4);
    margin-bottom: 1.3rem;
}
.diff-card h3 { font-size: 1.2rem; font-weight: 700; color: var(--white); margin-bottom: .8rem; }
.diff-card p  { font-size: .92rem; color: var(--muted); line-height: 1.7; }

/* ── CTA Section ─────────────────────────────────────────────── */
.cta-section { padding: 8rem 0; }

.cta-box {
    position: relative;
    background: var(--glass);
    border: 1px solid rgba(60,185,245,.2);
    border-radius: 28px;
    padding: 5rem 3rem;
    text-align: center;
    overflow: hidden;
    backdrop-filter: blur(8px);
}
.cta-gfx {
    position: absolute; inset: 0;
    background:
        radial-gradient(ellipse 70% 60% at 50% 50%, rgba(58,90,220,.15) 0%, transparent 70%),
        radial-gradient(ellipse 40% 40% at 20% 20%, rgba(60,185,245,.08) 0%, transparent 60%),
        radial-gradient(ellipse 40% 40% at 80% 80%, rgba(60,185,245,.08) 0%, transparent 60%);
    pointer-events: none;
}
.cta-box .section-label { position: relative; z-index: 1; }
.cta-box h2 {
    position: relative; z-index: 1;
    font-size: clamp(2rem, 4vw, 3rem); font-weight: 900; margin-bottom: 1rem;
}
.cta-box p {
    position: relative; z-index: 1;
    font-size: 1.05rem; color: var(--muted); max-width: 540px; margin: 0 auto 2.5rem;
}
.cta-btns {
    position: relative; z-index: 1;
    display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap;
}

/* ── Footer ──────────────────────────────────────────────────── */
.footer {
    padding: 5rem 0 2rem;
    border-top: 1px solid var(--border);
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}
.footer-brand .logo { margin-bottom: 1rem; }
.footer-brand p { font-size: .88rem; color: var(--muted); line-height: 1.7; margin-bottom: 1.5rem; }

.socials { display: flex; gap: .6rem; }
.soc-btn {
    width: 38px; height: 38px;
    border-radius: 10px;
    border: 1px solid var(--border);
    display: flex; align-items: center; justify-content: center;
    font-size: .9rem; color: var(--muted);
    transition: color .2s, border-color .2s, background .2s;
}
.soc-btn:hover { color: var(--blue-light); border-color: var(--blue-light); background: rgba(60,185,245,.08); }

.footer h4 { font-size: .85rem; font-weight: 700; text-transform: uppercase; letter-spacing: .1em; color: var(--white); margin-bottom: 1.2rem; }
.footer-links { list-style: none; display: flex; flex-direction: column; gap: .6rem; }
.footer-links a { font-size: .88rem; color: var(--muted); transition: color .2s; }
.footer-links a:hover { color: var(--blue-light); }

.footer-bottom {
    display: flex; align-items: center; gap: 1.5rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
}
.footer-bottom p { font-size: .82rem; color: var(--muted); }
.footer-line { flex: 1; height: 1px; background: var(--border); }

/* ═══════════════════════════════════════════════════════════════
   RESPONSIVE — Tablet (≤ 1024px)
═══════════════════════════════════════════════════════════════ */
@media (max-width: 1024px) {
    .hero-grid   { grid-template-columns: 1fr; text-align: center; gap: 3rem; }
    .hero-sub    { max-width: 100%; margin-left: auto; margin-right: auto; }
    .hero-actions{ justify-content: center; }
    .hero-metrics{ justify-content: center; }
    .hero-visual { order: -1; }
    .qviz        { width: 320px; height: 320px; }

    .about-grid  { grid-template-columns: 1fr; gap: 3rem; }
    .holo-card   { max-width: 480px; margin: 0 auto; }

    .r-grid      { grid-template-columns: 1fr 1fr; }
    .r-card:nth-child(3) { grid-column: 1 / -1; max-width: 480px; margin: 0 auto; }

    .footer-grid { grid-template-columns: 1fr 1fr; }
    .footer-brand{ grid-column: 1 / -1; }
}

/* ═══════════════════════════════════════════════════════════════
   RESPONSIVE — Mobile (≤ 768px)
═══════════════════════════════════════════════════════════════ */
@media (max-width: 768px) {
    /* Nav */
    .nav-menu {
        position: fixed;
        top: var(--nav-h); left: 0; right: 0;
        background: rgba(6,6,15,.97);
        backdrop-filter: blur(14px);
        flex-direction: column;
        padding: 1.5rem;
        gap: .25rem;
        z-index: 999;
        transform: translateY(-110%);
        transition: transform .35s cubic-bezier(.4,0,.2,1);
        border-bottom: 1px solid var(--border);
    }
    .nav-menu.active { transform: translateY(0); }
    .nav-link { padding: .85rem 1rem; font-size: 1rem; border-radius: var(--radius-sm); }
    .nav-right .btn-primary { display: none; }
    .hamburger { display: flex; }

    /* Hero */
    .hero { padding-top: calc(var(--nav-h) + 3rem); padding-bottom: 3rem; }
    .hero-content h1 { font-size: 2.6rem; }
    .qviz { width: 260px; height: 260px; }

    /* Cards */
    .r-grid      { grid-template-columns: 1fr; }
    .r-card:nth-child(3) { max-width: 100%; }
    .diff-grid   { grid-template-columns: 1fr; }

    /* About */
    .about-grid  { grid-template-columns: 1fr; }

    /* CTA */
    .cta-box { padding: 3rem 1.5rem; }

    /* Footer */
    .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
    .footer-brand{ grid-column: auto; }
    .footer-bottom { flex-direction: column; align-items: flex-start; gap: .75rem; }
    .footer-line { display: none; }

    /* Disable heavy animations */
    #neural-network { display: none; }
    body::before { animation: none; }
}

/* ═══════════════════════════════════════════════════════════════
   RESPONSIVE — Small Mobile (≤ 420px)
═══════════════════════════════════════════════════════════════ */
@media (max-width: 420px) {
    .hero-content h1 { font-size: 2rem; }
    .hero-actions    { flex-direction: column; }
    .btn-primary, .btn-ghost { width: 100%; justify-content: center; }
    .hero-metrics    { flex-direction: column; align-items: flex-start; gap: .75rem; }
    .metric-sep      { display: none; }
    .qviz            { width: 220px; height: 220px; }
    .cta-btns        { flex-direction: column; align-items: center; }
}