/* ============================================================
   Kinetic — an interactive showcase
   One stylesheet. No frameworks, no build step.
   ============================================================ */

/* ---------- Tokens ---------- */
:root {
  color-scheme: dark;

  --ink-900: #05060a;
  --ink-850: #080a11;
  --ink-800: #0b0e17;
  --ink-700: #11151f;
  --ink-600: #171c28;
  --line:    #232a3a;
  --line-soft: #1a2030;

  --text:     #e7ebf5;
  --text-dim: #9aa4bd;
  --text-mute:#6b7590;

  --accent:   #7c8cff;
  --accent-2: #3ad6c4;
  --accent-3: #ffb35c;
  --accent-4: #ff6b9a;

  --glow: 0 0 0 1px rgba(124,140,255,.25), 0 18px 60px -22px rgba(124,140,255,.55);
  --card-bg: linear-gradient(180deg, rgba(255,255,255,.045), rgba(255,255,255,.015));
  --card-border: rgba(255,255,255,.09);

  --radius: 16px;
  --radius-lg: 24px;
  --maxw: 1180px;

  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --ease: cubic-bezier(.16, 1, .3, 1);

  --noise: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

[data-theme="light"] {
  color-scheme: light;

  --ink-900: #f6f7fb;
  --ink-850: #ffffff;
  --ink-800: #ffffff;
  --ink-700: #f4f6fc;
  --ink-600: #eceff8;
  --line:    #dfe4f0;
  --line-soft: #e8ecf6;

  --text:     #12172a;
  --text-dim: #4d566f;
  --text-mute:#7c86a0;

  --accent:   #4a5bd8;
  --accent-2: #0f9e8d;
  --accent-3: #b96c05;
  --accent-4: #d4386f;

  --glow: 0 0 0 1px rgba(74,91,216,.18), 0 18px 50px -24px rgba(74,91,216,.45);
  --card-bg: linear-gradient(180deg, rgba(255,255,255,.92), rgba(255,255,255,.66));
  --card-border: rgba(18,23,42,.10);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}
body {
  margin: 0;
  font-family: var(--font);
  background: var(--ink-900);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background .5s var(--ease), color .5s var(--ease);
}
img, canvas, svg { display: block; max-width: 100%; }
button, input, select { font: inherit; color: inherit; }
a { color: inherit; }

/* ---------- Ambient background ---------- */
.aurora {
  position: fixed; inset: -20vmax; z-index: -2; pointer-events: none;
  filter: blur(90px); opacity: .5;
  transition: opacity .6s var(--ease);
}
[data-theme="light"] .aurora { opacity: .28; }
.aurora span { position: absolute; border-radius: 50%; animation: drift 26s var(--ease) infinite alternate; }
.aurora span:nth-child(1) { width: 46vmax; height: 46vmax; left: 4%;  top: 2%;   background: radial-gradient(circle, var(--accent), transparent 62%); }
.aurora span:nth-child(2) { width: 40vmax; height: 40vmax; right: 2%; top: 18%;  background: radial-gradient(circle, var(--accent-2), transparent 62%); animation-delay: -8s; }
.aurora span:nth-child(3) { width: 38vmax; height: 38vmax; left: 28%; bottom: 0%; background: radial-gradient(circle, var(--accent-4), transparent 62%); animation-delay: -15s; }
@keyframes drift {
  from { transform: translate3d(-4%, -3%, 0) scale(1); }
  to   { transform: translate3d(6%, 5%, 0) scale(1.18); }
}
.grain {
  position: fixed; inset: 0; z-index: -1; pointer-events: none; opacity: .04;
  background-image: var(--noise);
}

/* ---------- Layout ---------- */
.wrap { width: min(100% - 2.5rem, var(--maxw)); margin-inline: auto; }
section { padding: clamp(4rem, 9vw, 7.5rem) 0; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(14px) saturate(1.4);
  -webkit-backdrop-filter: blur(14px) saturate(1.4);
  background: color-mix(in srgb, var(--ink-900) 72%, transparent);
  border-bottom: 1px solid transparent;
  transition: border-color .3s var(--ease), background .3s var(--ease);
}
.site-header.stuck { border-bottom-color: var(--line); }
.nav { display: flex; align-items: center; gap: 1.25rem; height: 66px; }
.brand { display: flex; align-items: center; gap: .6rem; font-weight: 650; letter-spacing: -.02em; text-decoration: none; }
.brand .mark { width: 26px; height: 26px; flex: none; }
.nav-links { display: flex; gap: .2rem; margin-left: auto; }
.nav-links a {
  text-decoration: none; font-size: .875rem; color: var(--text-dim);
  padding: .45rem .7rem; border-radius: 9px; transition: color .2s, background .2s;
}
.nav-links a:hover, .nav-links a.active { color: var(--text); background: color-mix(in srgb, var(--text) 8%, transparent); }
@media (max-width: 860px) { .nav-links { display: none; } .nav { gap: .6rem; } }
@media (max-width: 860px) { .brand + .icon-btn, .nav .icon-btn { margin-left: auto; } }
.nav .icon-btn + .icon-btn { margin-left: 0; }

.icon-btn {
  display: grid; place-items: center; width: 38px; height: 38px; flex: none;
  border-radius: 11px; border: 1px solid var(--card-border);
  background: var(--card-bg); cursor: pointer;
  transition: transform .2s var(--ease), border-color .2s, box-shadow .25s;
}
.icon-btn:hover { transform: translateY(-2px); box-shadow: var(--glow); }
.icon-btn svg { width: 17px; height: 17px; }
.theme-toggle .sun { display: none; }
[data-theme="light"] .theme-toggle .sun { display: block; }
[data-theme="light"] .theme-toggle .moon { display: none; }

/* ---------- Hero ---------- */
.hero { position: relative; padding: 0; min-height: min(92svh, 860px); display: grid; }
.hero-canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
.hero-inner { position: relative; z-index: 2; align-self: center; padding: clamp(3rem, 8vw, 6rem) 0; pointer-events: none; }
.hero-inner > * { pointer-events: auto; }
.eyebrow {
  display: inline-flex; align-items: center; gap: .55rem;
  font-family: var(--mono); font-size: .72rem; letter-spacing: .16em; text-transform: uppercase;
  color: var(--text-dim); padding: .4rem .8rem; border-radius: 999px;
  border: 1px solid var(--card-border); background: var(--card-bg);
}
.eyebrow .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent-2); box-shadow: 0 0 10px var(--accent-2); animation: pulse 2.4s infinite; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: .3; } }

h1 {
  margin: 1.4rem 0 0;
  font-size: clamp(2.9rem, 8.5vw, 6.2rem);
  line-height: .95; letter-spacing: -.045em; font-weight: 680;
  max-width: 15ch;
}
.grad {
  background: linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 42%, var(--accent-3) 78%, var(--accent-4) 100%);
  background-size: 260% 100%;
  -webkit-background-clip: text; background-clip: text; color: transparent;
  animation: slide 14s linear infinite;
}
@keyframes slide { to { background-position: 260% 0; } }

.lede { margin: 1.5rem 0 0; max-width: 54ch; font-size: clamp(1.02rem, 1.6vw, 1.2rem); color: var(--text-dim); }
.cta-row { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 2.2rem; }
.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  padding: .8rem 1.35rem; border-radius: 12px; text-decoration: none;
  font-size: .92rem; font-weight: 550; cursor: pointer;
  border: 1px solid var(--card-border); background: var(--card-bg);
  transition: transform .25s var(--ease), box-shadow .3s, border-color .25s;
}
.btn:hover { transform: translateY(-3px); box-shadow: var(--glow); }
.btn-primary { border-color: transparent; background: linear-gradient(120deg, var(--accent), var(--accent-2)); color: #06070d; font-weight: 620; }
[data-theme="light"] .btn-primary { color: #fff; }

.scroll-hint {
  position: absolute; bottom: 1.8rem; left: 50%; translate: -50% 0; z-index: 2;
  font-family: var(--mono); font-size: .68rem; letter-spacing: .18em; text-transform: uppercase;
  color: var(--text-mute); display: grid; justify-items: center; gap: .5rem;
}
.scroll-hint .line { width: 1px; height: 34px; background: linear-gradient(var(--text-mute), transparent); animation: drop 2.2s infinite; }
@keyframes drop {
  0%   { transform: scaleY(0); transform-origin: top; }
  60%  { transform: scaleY(1); transform-origin: top; }
  100% { transform: scaleY(0); transform-origin: bottom; }
}

/* ---------- Section headings ---------- */
.sec-head { max-width: 62ch; margin-bottom: 2.6rem; }
.sec-num { font-family: var(--mono); font-size: .72rem; letter-spacing: .18em; color: var(--accent-2); text-transform: uppercase; }
.sec-head h2 { margin: .6rem 0 0; font-size: clamp(1.9rem, 4.2vw, 3rem); letter-spacing: -.035em; line-height: 1.05; font-weight: 660; }
.sec-head p { margin: .9rem 0 0; color: var(--text-dim); }

/* ---------- Demo cards ---------- */
.grid { display: grid; gap: 1.5rem; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(360px, 1fr)); }
.span-2 { grid-column: 1 / -1; }

.card {
  position: relative; overflow: hidden;
  border: 1px solid var(--card-border); border-radius: var(--radius-lg);
  background: var(--card-bg);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  transition: box-shadow .4s var(--ease), border-color .3s;
}
.card:hover { border-color: color-mix(in srgb, var(--accent) 32%, var(--card-border)); box-shadow: 0 30px 70px -40px rgba(0,0,0,.85); }
.card-head { display: flex; align-items: baseline; gap: .75rem; padding: 1.15rem 1.35rem .55rem; flex-wrap: wrap; }
.card-head h3 { margin: 0; font-size: 1.02rem; font-weight: 620; letter-spacing: -.015em; }
.card-head .tag {
  font-family: var(--mono); font-size: .64rem; letter-spacing: .12em; text-transform: uppercase;
  color: var(--accent-2); border: 1px solid color-mix(in srgb, var(--accent-2) 35%, transparent);
  padding: .16rem .5rem; border-radius: 999px; white-space: nowrap;
}
.card-head p { margin: .15rem 0 0; width: 100%; font-size: .87rem; color: var(--text-mute); }

.stage { position: relative; margin-top: .9rem; background: var(--ink-850); border-top: 1px solid var(--line-soft); border-bottom: 1px solid var(--line-soft); }
.stage canvas, .stage svg { width: 100%; display: block; touch-action: none; }
.stage.tall canvas   { height: 360px; }
.stage.medium canvas { height: 300px; }
.stage.short canvas  { height: 250px; }

.controls { display: flex; flex-wrap: wrap; align-items: center; gap: .55rem; padding: .85rem 1.2rem 1.1rem; }
.ctl {
  display: inline-flex; align-items: center; gap: .5rem;
  font-family: var(--mono); font-size: .72rem; letter-spacing: .04em;
  color: var(--text-dim); background: color-mix(in srgb, var(--text) 6%, transparent);
  border: 1px solid var(--card-border); border-radius: 10px; padding: .38rem .6rem;
}
.ctl label { text-transform: uppercase; font-size: .64rem; letter-spacing: .12em; color: var(--text-mute); }
.ctl input[type="range"] { -webkit-appearance: none; appearance: none; width: 88px; height: 3px; border-radius: 3px; background: var(--line); outline: none; }
.ctl input[type="range"]::-webkit-slider-thumb { -webkit-appearance: none; width: 13px; height: 13px; border-radius: 50%; background: var(--accent); cursor: pointer; border: 2px solid var(--ink-850); }
.ctl input[type="range"]::-moz-range-thumb { width: 13px; height: 13px; border: 2px solid var(--ink-850); border-radius: 50%; background: var(--accent); cursor: pointer; }
.ctl select { background: transparent; border: none; outline: none; cursor: pointer; font-family: var(--mono); font-size: .72rem; }
.ctl select option { background: var(--ink-700); color: var(--text); }
.ctl .val { color: var(--accent-2); min-width: 3ch; text-align: right; font-variant-numeric: tabular-nums; }

button.pill {
  font-family: var(--mono); font-size: .72rem; letter-spacing: .05em;
  padding: .45rem .85rem; border-radius: 10px; cursor: pointer;
  border: 1px solid var(--card-border); background: color-mix(in srgb, var(--text) 6%, transparent);
  color: var(--text-dim);
  transition: color .2s, border-color .2s, transform .2s var(--ease), background .2s;
}
button.pill:hover { color: var(--text); border-color: color-mix(in srgb, var(--accent) 50%, transparent); transform: translateY(-1px); }
button.pill.on { color: #06070d; background: linear-gradient(120deg, var(--accent), var(--accent-2)); border-color: transparent; }
[data-theme="light"] button.pill.on { color: #fff; }

.hint { font-family: var(--mono); font-size: .68rem; color: var(--text-mute); margin-left: auto; letter-spacing: .04em; }
.readout { font-family: var(--mono); font-size: .68rem; color: var(--text-mute); letter-spacing: .04em; }
.readout b { color: var(--accent-2); font-weight: 500; font-variant-numeric: tabular-nums; }

/* ---------- Metrics ---------- */
.metrics { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 1px; background: var(--line-soft); border: 1px solid var(--card-border); border-radius: var(--radius); overflow: hidden; }
.metric { background: var(--ink-850); padding: 1.4rem 1.2rem; }
.metric .n { font-size: clamp(1.6rem, 3.4vw, 2.3rem); font-weight: 660; letter-spacing: -.03em; font-variant-numeric: tabular-nums; }
.metric .k { font-family: var(--mono); font-size: .66rem; text-transform: uppercase; letter-spacing: .14em; color: var(--text-mute); margin-top: .3rem; }

/* ---------- Code peek ---------- */
.code {
  font-family: var(--mono); font-size: .78rem; line-height: 1.75;
  background: var(--ink-850); border: 1px solid var(--card-border);
  border-radius: var(--radius); padding: 1.1rem 1.25rem; overflow-x: auto; color: var(--text-dim);
  margin: 0;
}
.c-key { color: var(--accent); }
.c-str { color: var(--accent-2); }
.c-com { color: var(--text-mute); font-style: italic; }
.c-num { color: var(--accent-3); }

/* ---------- Footer ---------- */
footer { border-top: 1px solid var(--line); padding: 3rem 0 4rem; }
.foot { display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; justify-content: space-between; color: var(--text-mute); font-size: .85rem; }
.foot a { color: var(--text-dim); text-decoration: none; border-bottom: 1px solid transparent; transition: .2s; }
.foot a:hover { color: var(--text); border-bottom-color: var(--accent); }

/* ---------- Reveal ---------- */
.js .reveal { opacity: 0; transform: translateY(26px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.js .reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .js .reveal { opacity: 1; transform: none; } }

/* ---------- Utility ---------- */
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }