/* ============================================================
   Gravometric — design system
   Palette : ink slate base, electric cyan accent, soft signal violet
   Type    : Space Grotesk (display) · Inter (body) · JetBrains Mono (data)
   ============================================================ */

:root {
  --ink-900: #0A1019;
  --ink-850: #0E1622;
  --ink-800: #121C2B;
  --ink-700: #1A2638;
  --ink-600: #243349;
  --line:    #2A3A52;
  --fog-300: #8EA0B8;
  --fog-200: #B4C2D4;
  --fog-100: #E4EBF3;
  --paper:   #F5F8FC;

  --accent:  #29E0D6;   /* electric cyan */
  --accent-deep: #15B3AB;
  --violet:  #8B7CF6;   /* signal violet, used very sparingly */

  --ok:   #34D399;
  --rev:  #FBBF24;

  --display: "Space Grotesk", system-ui, sans-serif;
  --body: "Inter", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;

  --maxw: 1140px;
  --gutter: clamp(1.1rem, 4vw, 2.5rem);
  --radius: 14px;
  --radius-sm: 9px;

  --t-fast: 140ms cubic-bezier(.4,0,.2,1);
  --t-med:  280ms cubic-bezier(.4,0,.2,1);
}

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--fog-100);
  background: var(--ink-900);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; padding: 0; }
button { font: inherit; cursor: pointer; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; }
}

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: 1rem; top: -3rem; z-index: 200;
  background: var(--accent); color: var(--ink-900); font-weight: 600;
  padding: .6rem 1rem; border-radius: var(--radius-sm); transition: top var(--t-fast);
}
.skip-link:focus { top: 1rem; }

.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }

/* ---------- typography helpers ---------- */
.eyebrow {
  font-family: var(--mono);
  font-size: .8rem; letter-spacing: .14em; text-transform: uppercase;
  color: var(--accent); margin-bottom: 1rem;
}
.mono { font-family: var(--mono); }
.dim { color: var(--fog-300); }

.section__title {
  font-family: var(--display);
  font-weight: 600;
  font-size: clamp(1.7rem, 1rem + 2.6vw, 2.7rem);
  line-height: 1.1;
  letter-spacing: -.015em;
  color: var(--paper);
}
.section__intro, .section__head .section__title + p {
  color: var(--fog-200); max-width: 56ch; margin-top: 1rem; font-size: 1.05rem;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font-family: var(--display); font-weight: 500; font-size: .98rem;
  padding: .72rem 1.3rem; border-radius: var(--radius-sm);
  border: 1px solid transparent; transition: background var(--t-fast), color var(--t-fast),
    border-color var(--t-fast), transform var(--t-fast), box-shadow var(--t-fast);
  white-space: nowrap;
}
.btn--lg { padding: .9rem 1.6rem; font-size: 1.02rem; }
.btn--block { width: 100%; }
.btn--primary {
  background: var(--accent-deep); color: #fff; font-weight: 600;
  box-shadow: 0 0 0 0 rgba(41,224,214,.45);
}
.btn--primary:hover { background: var(--accent); color: #000; transform: translateY(-1px); box-shadow: 0 10px 28px -12px rgba(41,224,214,.6); }
.btn--primary:active { transform: translateY(0); background: #0E9A93; }
.btn--ghost { background: transparent; color: var(--fog-100); border-color: var(--line); }
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: color-mix(in srgb, var(--ink-900) 82%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--t-med), background var(--t-med);
}
.site-header.is-scrolled { border-bottom-color: var(--line); background: color-mix(in srgb, var(--ink-900) 94%, transparent); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }

.wordmark { display: inline-flex; align-items: center; gap: .55rem; }
.wordmark__text { font-family: var(--display); font-weight: 700; font-size: 1.2rem; letter-spacing: -.02em; color: var(--paper); }
.mk-node { fill: var(--accent); }
.mk-edge { stroke: var(--fog-300); stroke-width: 1.4; }

.nav { display: flex; align-items: center; }
.nav__menu { display: flex; align-items: center; gap: 1.6rem; }
.nav__menu a { font-size: .95rem; color: var(--fog-200); transition: color var(--t-fast); }
.nav__menu a:not(.btn):hover { color: var(--accent); }
.nav__menu a:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; border-radius: 3px; }
.nav__cta { margin-left: .4rem; }

.nav__toggle {
  display: none; width: 42px; height: 42px; border: 1px solid var(--line);
  border-radius: var(--radius-sm); background: transparent; position: relative;
}
.nav__toggle-bar, .nav__toggle-bar::before, .nav__toggle-bar::after {
  content: ""; position: absolute; left: 50%; top: 50%; width: 18px; height: 2px;
  background: var(--fog-100); transform: translate(-50%,-50%); transition: transform var(--t-fast), opacity var(--t-fast);
}
.nav__toggle-bar::before { transform: translate(-50%,-7px); }
.nav__toggle-bar::after { transform: translate(-50%,5px); }
.nav__toggle[aria-expanded="true"] .nav__toggle-bar { background: transparent; }
.nav__toggle[aria-expanded="true"] .nav__toggle-bar::before { transform: translate(-50%,-50%) rotate(45deg); }
.nav__toggle[aria-expanded="true"] .nav__toggle-bar::after { transform: translate(-50%,-50%) rotate(-45deg); }
.nav__toggle:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

/* ---------- hero ---------- */
.hero { position: relative; padding-top: clamp(2.5rem, 5vw, 4.5rem); padding-bottom: clamp(3rem, 6vw, 5.5rem); overflow: hidden; }
.hero__grid-bg {
  position: absolute; inset: 0; z-index: 0; pointer-events: none;
  background:
    radial-gradient(900px 480px at 78% 8%, rgba(41,224,214,.10), transparent 60%),
    radial-gradient(700px 500px at 10% 100%, rgba(139,124,246,.08), transparent 60%),
    linear-gradient(transparent 0 calc(100% - 1px), var(--line) 100%) 0 0 / 100% 56px,
    linear-gradient(90deg, transparent 0 calc(100% - 1px), var(--line) 100%) 0 0 / 56px 100%;
  -webkit-mask-image: radial-gradient(120% 90% at 70% 10%, #000 30%, transparent 78%);
          mask-image: radial-gradient(120% 90% at 70% 10%, #000 30%, transparent 78%);
  opacity: .5;
}
.hero__inner { position: relative; z-index: 1; display: grid; grid-template-columns: 1.15fr .85fr; gap: clamp(1.5rem, 4vw, 3.5rem); align-items: center; }
.hero__title {
  font-family: var(--display); font-weight: 700;
  font-size: clamp(2.3rem, 1rem + 5vw, 4.3rem); line-height: 1.04; letter-spacing: -.03em;
  color: var(--paper); margin-bottom: 1.3rem;
}
.hero__lead { font-size: clamp(1.05rem, 1rem + .4vw, 1.25rem); color: var(--fog-200); max-width: 46ch; margin-bottom: 1.4rem; }
.hero__capability { font-family: var(--mono); font-size: .85rem; color: var(--fog-300); letter-spacing: .02em; margin-bottom: 2rem; }
.hero__capability span { color: var(--accent); margin-inline: .15rem; }
.hero__actions { display: flex; flex-wrap: wrap; gap: .9rem; }

/* hero diagram */
.hero__diagram { display: flex; justify-content: center; }
.pipeline { width: 100%; max-width: 380px; }
.pipe-edges path { fill: none; stroke: var(--line); stroke-width: 1.5; }
.pipe-flow path { fill: none; stroke: url(#flow); stroke-width: 2.5; stroke-linecap: round;
  stroke-dasharray: 26 280; animation: dash 3.4s linear infinite; }
.pipe-flow path:nth-child(2) { animation-delay: -1.1s; }
.pipe-flow path:nth-child(3) { animation-delay: -2.2s; }
@keyframes dash { to { stroke-dashoffset: -306; } }
.pipe-nodes circle { fill: var(--ink-700); stroke: var(--fog-300); stroke-width: 1.5; }
.pipe-nodes circle.hub { fill: var(--ink-600); stroke: var(--accent); }
.pipe-nodes circle.model { fill: rgba(139,124,246,.18); stroke: var(--violet); }
.pipe-nodes text { fill: var(--fog-200); font-size: 11px; font-family: var(--mono); }

/* ---------- problem statement ---------- */
.problem { padding-block: clamp(2.5rem, 5vw, 4rem); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--ink-850); }
.problem__text { font-family: var(--display); font-weight: 400; font-size: clamp(1.25rem, 1rem + 1.5vw, 1.9rem); line-height: 1.4; color: var(--fog-100); max-width: 30ch; max-width: 64ch; letter-spacing: -.01em; }
.problem__text em { font-style: normal; color: var(--accent); }

/* ---------- generic section ---------- */
.section { padding-block: clamp(3.5rem, 7vw, 6rem); }
.section--muted { background: var(--ink-850); border-block: 1px solid var(--line); }
.section__head { margin-bottom: clamp(2rem, 4vw, 3rem); }

/* ---------- service cards ---------- */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 1.1rem; }
.card {
  position: relative; background: var(--ink-800); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.5rem 1.4rem 1.6rem;
  transition: border-color var(--t-med), transform var(--t-med), box-shadow var(--t-med);
  overflow: hidden;
}
.card::before { content: ""; position: absolute; inset: 0 0 auto 0; height: 2px; background: linear-gradient(90deg, var(--accent), transparent 70%); opacity: 0; transition: opacity var(--t-med); }
.card:hover { border-color: var(--ink-600); transform: translateY(-3px); box-shadow: 0 20px 40px -28px rgba(0,0,0,.8); }
.card:hover::before { opacity: 1; }
.card__index { font-family: var(--mono); font-size: .78rem; color: var(--accent); }
.card__title { font-family: var(--display); font-weight: 600; font-size: 1.22rem; color: var(--paper); margin: .5rem 0 .55rem; letter-spacing: -.01em; }
.card__summary { color: var(--fog-200); font-size: .96rem; margin-bottom: 1rem; }
.card__points { display: flex; flex-direction: column; gap: .4rem; }
.card__points li { position: relative; padding-left: 1.1rem; font-size: .9rem; color: var(--fog-300); }
.card__points li::before { content: ""; position: absolute; left: 0; top: .55em; width: 6px; height: 6px; border-radius: 2px; background: var(--accent); opacity: .7; }

/* ---------- featured solution ---------- */
.section--feature { background: var(--ink-850); border-block: 1px solid var(--line); }
.feature { display: grid; grid-template-columns: 1.1fr .9fr; gap: clamp(1.8rem, 4vw, 3.5rem); align-items: center; }
.feature__lead { color: var(--fog-200); margin: 1.1rem 0 1.4rem; font-size: 1.05rem; }
.feature__list { display: grid; grid-template-columns: 1fr 1fr; gap: .55rem 1.4rem; margin-bottom: 1.4rem; }
.feature__list li { position: relative; padding-left: 1.3rem; font-size: .92rem; color: var(--fog-200); }
.feature__list li::before { content: "→"; position: absolute; left: 0; color: var(--accent); font-family: var(--mono); }
.feature__note { font-size: .92rem; color: var(--fog-300); border-left: 2px solid var(--accent); padding-left: 1rem; margin-bottom: 1.6rem; max-width: 60ch; }

.feature__visual { display: flex; justify-content: center; }
.glossary-card {
  width: 100%; max-width: 380px; background: var(--ink-800); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.2rem; box-shadow: 0 30px 60px -40px rgba(0,0,0,.9);
}
.glossary-card__row { display: grid; grid-template-columns: 1.4fr 1fr .9fr; align-items: center; gap: .6rem; padding: .6rem .2rem; border-bottom: 1px solid var(--ink-700); font-size: .88rem; }
.glossary-card__row:last-of-type { border-bottom: 0; }
.glossary-card__row--head { color: var(--fog-300); font-size: .74rem; letter-spacing: .08em; text-transform: uppercase; }
.glossary-card__row span:first-child { color: var(--fog-100); font-weight: 500; }
.pill { font-family: var(--mono); font-size: .7rem; padding: .18rem .5rem; border-radius: 100px; text-align: center; }
.pill--ok { background: rgba(52,211,153,.14); color: var(--ok); }
.pill--rev { background: rgba(251,191,36,.14); color: var(--rev); }
.glossary-card__lineage { margin-top: .9rem; padding-top: .8rem; border-top: 1px dashed var(--ink-600); font-size: .72rem; color: var(--fog-300); }

/* ---------- databricks diagram ---------- */
.feature--reverse { direction: ltr; }
.feature--reverse .feature__body { order: 2; }
.feature--reverse .feature__visual { order: 1; }
.databricks-diagram { width: 100%; max-width: 380px; }
.db-flow path { stroke-dasharray: 16 180; animation: dbpulse 2.8s linear infinite; }
.db-flow path:nth-child(2) { animation-delay: -.9s; }
.db-flow path:nth-child(3) { animation-delay: -1.8s; }
@keyframes dbpulse { to { stroke-dashoffset: -196; } }

/* ---------- use cases ---------- */
.use-cases { display: grid; grid-template-columns: repeat(auto-fill, minmax(330px, 1fr)); gap: 1.1rem; counter-reset: uc; }
.use-case {
  background: var(--ink-800); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.5rem 1.4rem; transition: border-color var(--t-med), transform var(--t-med);
}
.use-case:hover { border-color: var(--ink-600); transform: translateY(-3px); }
.use-case__num { counter-increment: uc; font-family: var(--mono); font-size: .8rem; color: var(--accent); }
.use-case__num::before { content: counter(uc, decimal-leading-zero); }
.use-case__title { font-family: var(--display); font-weight: 600; font-size: 1.12rem; color: var(--paper); margin: .5rem 0 .6rem; line-height: 1.25; }
.use-case__body { color: var(--fog-300); font-size: .94rem; }

/* ---------- expertise ---------- */
.tech-list { display: flex; flex-wrap: wrap; gap: .6rem; margin-bottom: clamp(2.5rem, 5vw, 4rem); }
.tech-list li {
  font-family: var(--mono); font-size: .85rem; color: var(--fog-200);
  border: 1px solid var(--line); border-radius: 100px; padding: .42rem .9rem;
  background: var(--ink-800); transition: border-color var(--t-fast), color var(--t-fast);
}
.tech-list li:hover { border-color: var(--accent); color: var(--accent); }

.why__title { font-family: var(--display); font-weight: 600; font-size: 1.5rem; color: var(--paper); margin-bottom: 1.4rem; }
.why__grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 1.1rem; }
.why-item { border-top: 2px solid var(--ink-600); padding-top: 1rem; }
.why-item h4 { font-family: var(--display); font-weight: 600; font-size: 1.05rem; color: var(--fog-100); margin-bottom: .4rem; }
.why-item p { color: var(--fog-300); font-size: .92rem; }

/* ---------- how we work ---------- */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 1.4rem; }
.step { position: relative; padding-top: 1.4rem; border-top: 1px solid var(--line); }
.step__n { display: inline-flex; align-items: center; gap: .5rem; font-family: var(--mono); font-size: .8rem; color: var(--accent); margin-bottom: .7rem; }
.step__n b { width: 26px; height: 26px; display: grid; place-items: center; border: 1px solid var(--accent); border-radius: 7px; font-weight: 500; }
.step__title { font-family: var(--display); font-weight: 600; font-size: 1.15rem; color: var(--paper); margin-bottom: .5rem; }
.step__body { color: var(--fog-300); font-size: .92rem; }

/* ---------- contact ---------- */
.section--contact { background: var(--ink-850); border-top: 1px solid var(--line); }
.contact { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2rem, 5vw, 4rem); align-items: start; }
.contact__lead { color: var(--fog-200); margin: 1rem 0 1.8rem; font-size: 1.05rem; max-width: 46ch; }
.contact__details { display: grid; gap: 1.1rem; }
.contact__details dt { font-family: var(--mono); font-size: .74rem; letter-spacing: .1em; text-transform: uppercase; color: var(--fog-300); margin-bottom: .2rem; }
.contact__details dd { color: var(--fog-100); }
.contact__details a { color: var(--accent); border-bottom: 1px solid transparent; transition: border-color var(--t-fast); }
.contact__details a:hover { border-bottom-color: var(--accent); }

.contact__form { background: var(--ink-800); border: 1px solid var(--line); border-radius: var(--radius); padding: clamp(1.4rem, 3vw, 2rem); }
.field { margin-bottom: 1.1rem; }
.field label { display: block; font-size: .85rem; color: var(--fog-200); margin-bottom: .4rem; font-weight: 500; }
.field input, .field select, .field textarea {
  width: 100%; font: inherit; font-size: .95rem; color: var(--fog-100);
  background: var(--ink-850); border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: .7rem .85rem; transition: border-color var(--t-fast), box-shadow var(--t-fast);
}
.field textarea { resize: vertical; min-height: 100px; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(41,224,214,.16);
}
.field input::placeholder, .field textarea::placeholder { color: var(--fog-300); }
.field--invalid input, .field--invalid select, .field--invalid textarea { border-color: #F87171; }
.field__error { display: block; min-height: 1rem; margin-top: .35rem; font-size: .8rem; color: #FCA5A5; }
.field--hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }

.contact__privacy { font-size: .82rem; color: var(--fog-300); margin-top: 1rem; }
.contact__privacy a { color: var(--accent); }
.contact__status { margin-top: 1rem; font-size: .92rem; min-height: 1.2rem; }
.contact__status.is-ok { color: var(--ok); }
.contact__status.is-err { color: #FCA5A5; }

/* ---------- footer ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--ink-900); padding-top: clamp(2.5rem, 5vw, 3.5rem); }
.footer-inner { display: flex; justify-content: space-between; gap: 2rem; flex-wrap: wrap; padding-bottom: 2rem; }
.footer__tag { color: var(--fog-300); font-size: .9rem; margin-top: .7rem; max-width: 32ch; }
.footer__links { display: flex; flex-direction: column; gap: .7rem; align-items: flex-start; }
.footer__links a { color: var(--fog-200); font-size: .92rem; transition: color var(--t-fast); border-bottom: 1px solid transparent; }
.footer__links a:hover { color: var(--accent); }
.footer__base { border-top: 1px solid var(--line); padding-block: 1.3rem; }
.footer__base p { color: var(--fog-300); font-size: .85rem; }

/* ---------- reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity var(--t-med), transform var(--t-med); }
.reveal.is-in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; } }

/* ---------- responsive ---------- */
@media (max-width: 880px) {
  .hero__inner { grid-template-columns: 1fr; }
  .hero__diagram { order: -1; max-width: 320px; margin-inline: auto; }
  .feature { grid-template-columns: 1fr; }
  .contact { grid-template-columns: 1fr; }
  .feature__visual { order: -1; }
}

@media (max-width: 760px) {
  .nav__toggle { display: inline-flex; }
  .nav__menu {
    position: fixed; inset: 68px 0 auto 0; flex-direction: column; align-items: stretch;
    gap: 0; background: var(--ink-850); border-bottom: 1px solid var(--line);
    padding: .5rem var(--gutter) 1.2rem; transform: translateY(-12px); opacity: 0;
    pointer-events: none; transition: opacity var(--t-fast), transform var(--t-fast);
  }
  .nav__menu.is-open { transform: none; opacity: 1; pointer-events: auto; }
  .nav__menu li { border-bottom: 1px solid var(--ink-700); }
  .nav__menu li:last-child { border-bottom: 0; }
  .nav__menu a:not(.btn) { display: block; padding: .9rem .2rem; }
  .nav__cta { margin: .9rem 0 0; }
  .nav__cta .btn { width: 100%; }
  .feature__list { grid-template-columns: 1fr; }
}

@media (max-width: 420px) {
  .hero__actions .btn { width: 100%; }
}