/* =========================================================================
   FieldMesh Data — design system
   Dark carbon surfaces, cyan/teal accent. Frontier AI infrastructure tone.
   ========================================================================= */

:root {
  /* Type scale (fluid) */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --text-sm: clamp(0.8125rem, 0.78rem + 0.2vw, 0.875rem);
  --text-base: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --text-lg: clamp(1.125rem, 1rem + 0.5vw, 1.375rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.3rem + 2.4vw, 3.4rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 4.75rem);

  /* Spacing (4px base) */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  --transition-interactive: 200ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Content widths */
  --content-narrow: 680px;
  --content-default: 1000px;
  --content-wide: 1240px;

  /* Fonts (Fontshare) */
  --font-display: 'Clash Grotesk', 'Satoshi', system-ui, sans-serif;
  --font-body: 'Satoshi', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Space Mono', ui-monospace, monospace;
}

/* ---------- DARK (primary) ---------- */
:root,
[data-theme='dark'] {
  --color-bg: #0a0c0e;
  --color-bg-2: #0d1013;
  --color-surface: #111519;
  --color-surface-2: #161b20;
  --color-surface-3: #1b2228;
  --color-border: #232b32;
  --color-border-strong: #2f3942;
  --color-grid: rgba(120, 200, 210, 0.045);

  --color-text: #e6edf1;
  --color-text-muted: #93a1ab;
  --color-text-faint: #5e6c75;
  --color-text-inverse: #06090b;

  --color-primary: #2fd4cf;        /* cyan/teal accent */
  --color-primary-bright: #5af2ec;
  --color-primary-hover: #58e3de;
  --color-primary-dim: rgba(47, 212, 207, 0.14);
  --color-primary-line: rgba(47, 212, 207, 0.34);

  --color-success: #5fcf7e;
  --color-warning: #e0a44a;
  --color-amber: #e0a44a;

  --glow: 0 0 0 1px var(--color-primary-line), 0 0 28px rgba(47, 212, 207, 0.18);
  --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 24px 60px rgba(0, 0, 0, 0.6);
}

/* ---------- LIGHT ---------- */
[data-theme='light'] {
  --color-bg: #f4f6f7;
  --color-bg-2: #eef1f3;
  --color-surface: #ffffff;
  --color-surface-2: #f6f8f9;
  --color-surface-3: #eef2f4;
  --color-border: #dde3e7;
  --color-border-strong: #c6cfd5;
  --color-grid: rgba(20, 90, 95, 0.05);

  --color-text: #0e1417;
  --color-text-muted: #4a575f;
  --color-text-faint: #8794a0;
  --color-text-inverse: #ffffff;

  --color-primary: #0a8f8a;
  --color-primary-bright: #0a8f8a;
  --color-primary-hover: #097a76;
  --color-primary-dim: rgba(10, 143, 138, 0.1);
  --color-primary-line: rgba(10, 143, 138, 0.28);

  --color-success: #2e8b4f;
  --color-warning: #b8791f;
  --color-amber: #b8791f;

  --glow: 0 0 0 1px var(--color-primary-line), 0 6px 24px rgba(10, 143, 138, 0.12);
  --shadow-md: 0 8px 24px rgba(20, 40, 45, 0.1);
  --shadow-lg: 0 24px 50px rgba(20, 40, 45, 0.14);
}

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

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: 6rem;
}

body {
  min-height: 100dvh;
  line-height: 1.62;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  overflow-x: hidden;
}

img, picture, video, canvas, svg { display: block; max-width: 100%; height: auto; }
ul[role='list'] { list-style: none; }
input, button, textarea, select { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: none; }

h1, h2, h3, h4 { text-wrap: balance; line-height: 1.08; font-family: var(--font-display); font-weight: 600; letter-spacing: -0.02em; }
p { text-wrap: pretty; }

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

::selection { background: var(--color-primary-dim); color: var(--color-text); }

:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 3px; border-radius: var(--radius-sm); }

a, button, [role='button'], input, textarea, select {
  transition: color var(--transition-interactive), background var(--transition-interactive),
    border-color var(--transition-interactive), box-shadow var(--transition-interactive),
    transform var(--transition-interactive), opacity var(--transition-interactive);
}

.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border-width: 0; }

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

/* ===================== layout primitives ===================== */
.wrap { width: 100%; max-width: var(--content-wide); margin-inline: auto; padding-inline: clamp(1.25rem, 4vw, 3rem); }
.wrap-narrow { max-width: var(--content-default); }

section { position: relative; }
.section-pad { padding-block: clamp(var(--space-10), 6vw, var(--space-20)); }
.section-pad-sm { padding-block: clamp(var(--space-8), 4vw, var(--space-12)); }

.eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--color-primary); font-weight: 500;
}
.eyebrow::before { content: ''; width: 22px; height: 1px; background: var(--color-primary-line); }

.muted { color: var(--color-text-muted); }
.faint { color: var(--color-text-faint); }
.lead { font-size: var(--text-lg); color: var(--color-text-muted); line-height: 1.55; max-width: 60ch; }

.grid-bg {
  background-image:
    linear-gradient(var(--color-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-grid) 1px, transparent 1px);
  background-size: 46px 46px;
}

/* ===================== buttons ===================== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  font-size: var(--text-sm); font-weight: 600; letter-spacing: -0.01em;
  padding: 0.7rem 1.3rem; border-radius: var(--radius-md);
  border: 1px solid transparent; white-space: nowrap;
}
.btn svg { width: 16px; height: 16px; }
.btn-primary { background: var(--color-primary); color: var(--color-text-inverse); }
.btn-primary:hover { background: var(--color-primary-hover); transform: translateY(-1px); box-shadow: 0 6px 22px rgba(47,212,207,0.28); }
.btn-ghost { border-color: var(--color-border-strong); color: var(--color-text); background: color-mix(in oklab, var(--color-surface) 60%, transparent); }
.btn-ghost:hover { border-color: var(--color-primary-line); color: var(--color-primary); }
.btn-lg { padding: 0.85rem 1.6rem; font-size: var(--text-base); }

/* ===================== chips / tags ===================== */
.chip {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.04em;
  padding: 0.3rem 0.65rem; border-radius: var(--radius-full);
  border: 1px solid var(--color-border); color: var(--color-text-muted);
  background: var(--color-surface);
}
.chip .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--color-primary); box-shadow: 0 0 8px var(--color-primary); }
.chip-status .dot { background: var(--color-success); box-shadow: 0 0 8px var(--color-success); }
.chip-scoping .dot { background: var(--color-amber); box-shadow: 0 0 8px var(--color-amber); }

/* ===================== cards / panels ===================== */
.panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  position: relative;
}
.panel-glow:hover { border-color: var(--color-primary-line); }

/* data panel with corner ticks */
.data-panel {
  background: linear-gradient(180deg, var(--color-surface) 0%, var(--color-bg-2) 100%);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  position: relative;
  overflow: hidden;
  transition: border-color var(--transition-interactive), transform var(--transition-interactive);
}
.data-panel::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(120% 80% at 0% 0%, var(--color-primary-dim), transparent 55%);
  opacity: 0; transition: opacity var(--transition-interactive); pointer-events: none;
}
.data-panel:hover { border-color: var(--color-primary-line); transform: translateY(-3px); }
.data-panel:hover::before { opacity: 1; }

.panel-num { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-primary); letter-spacing: 0.1em; }

/* ===================== header ===================== */
.site-header {
  position: sticky; top: 0; z-index: 60;
  background: color-mix(in oklab, var(--color-bg) 78%, transparent);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 68px; gap: var(--space-6); }
.brand { display: flex; align-items: center; gap: var(--space-3); font-family: var(--font-display); font-weight: 600; letter-spacing: -0.02em; font-size: 1.0625rem; }
.brand .logo { width: 30px; height: 30px; color: var(--color-primary); flex-shrink: 0; }
.brand small { font-family: var(--font-mono); font-weight: 400; font-size: 0.6rem; letter-spacing: 0.22em; color: var(--color-text-faint); text-transform: uppercase; }
.nav-links { display: flex; align-items: center; gap: var(--space-1); }
.nav-links a {
  font-size: var(--text-sm); color: var(--color-text-muted); font-weight: 500;
  padding: 0.5rem 0.8rem; border-radius: var(--radius-sm);
}
.nav-links a:hover { color: var(--color-text); }
.nav-links a.active { color: var(--color-text); }
.nav-actions { display: flex; align-items: center; gap: var(--space-3); }
.theme-toggle { width: 38px; height: 38px; display: grid; place-items: center; border-radius: var(--radius-sm); border: 1px solid var(--color-border); color: var(--color-text-muted); }
.theme-toggle:hover { color: var(--color-primary); border-color: var(--color-primary-line); }
.menu-btn { display: none; width: 38px; height: 38px; place-items: center; border-radius: var(--radius-sm); border: 1px solid var(--color-border); color: var(--color-text); }

/* ===================== hero ===================== */
.hero { position: relative; padding-block: clamp(var(--space-14, 3.5rem), 8vw, var(--space-24)); overflow: hidden; }
.hero::after {
  content: ''; position: absolute; inset: 0; pointer-events: none; z-index: 0;
  background:
    radial-gradient(60% 50% at 70% 0%, rgba(47,212,207,0.1), transparent 60%),
    radial-gradient(40% 40% at 10% 90%, rgba(47,212,207,0.06), transparent 60%);
}
.hero .wrap { position: relative; z-index: 1; }
.hero h1 { font-size: var(--text-3xl); font-weight: 600; line-height: 1.02; }
.hero h1 .accent { color: var(--color-primary); }

/* ===================== utilities ===================== */
.flex { display: flex; }
.btn-row { display: flex; flex-wrap: wrap; gap: var(--space-3); }
.center { text-align: center; }
.divider { height: 1px; background: var(--color-border); border: 0; }

.grid { display: grid; gap: var(--space-6); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.section-head { max-width: 64ch; margin-bottom: var(--space-8); }
.section-head h2 { font-size: var(--text-2xl); margin-top: var(--space-4); }
.section-head p { margin-top: var(--space-4); }

/* split positioning cards */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-6); }
.split-card {
  border: 1px solid var(--color-border); border-radius: var(--radius-xl);
  padding: clamp(var(--space-6), 4vw, var(--space-10));
  background: linear-gradient(180deg, var(--color-surface) 0%, var(--color-bg-2) 100%);
  position: relative; overflow: hidden;
  transition: border-color var(--transition-interactive);
}
.split-card:hover { border-color: var(--color-primary-line); }
.split-card .kicker { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-primary); }
.split-card h3 { font-size: var(--text-xl); margin: var(--space-4) 0 var(--space-3); }
.split-card ul { list-style: none; margin: var(--space-5) 0; display: grid; gap: var(--space-3); }
.split-card li { display: flex; gap: var(--space-3); font-size: var(--text-sm); color: var(--color-text-muted); align-items: flex-start; }
.split-card li svg { width: 16px; height: 16px; color: var(--color-primary); flex-shrink: 0; margin-top: 3px; }

/* stat strip */
.stat-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-6); border-top: 1px solid var(--color-border); border-bottom: 1px solid var(--color-border); padding-block: var(--space-6); }
.stat .num { font-family: var(--font-display); font-size: var(--text-xl); font-weight: 600; color: var(--color-text); letter-spacing: -0.02em; }
.stat .num .unit { color: var(--color-primary); }
.stat .label { font-size: var(--text-sm); color: var(--color-text-muted); margin-top: var(--space-2); }

/* process timeline */
.timeline { display: grid; gap: 0; }
.tl-step { display: grid; grid-template-columns: auto 1fr; gap: var(--space-6); padding-bottom: var(--space-6); position: relative; }
.tl-step:last-child { padding-bottom: 0; }
.tl-marker { display: flex; flex-direction: column; align-items: center; }
.tl-dot { width: 36px; height: 36px; border-radius: var(--radius-md); border: 1px solid var(--color-primary-line); background: var(--color-surface); display: grid; place-items: center; font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-primary); flex-shrink: 0; }
.tl-line { width: 1px; flex: 1; background: var(--color-border); margin-top: var(--space-2); }
.tl-step:last-child .tl-line { display: none; }
.tl-body h3 { font-size: var(--text-lg); margin-bottom: var(--space-2); }
.tl-body p { font-size: var(--text-sm); color: var(--color-text-muted); max-width: 60ch; }

/* environment cards */
.env-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-5); }
.env-card {
  border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  background: var(--color-surface); padding: var(--space-6); position: relative; overflow: hidden;
  transition: border-color var(--transition-interactive), transform var(--transition-interactive);
}
.env-card:hover { border-color: var(--color-primary-line); transform: translateY(-3px); }
.env-card .env-icon { width: 40px; height: 40px; color: var(--color-primary); margin-bottom: var(--space-4); }
.env-card h3 { font-size: var(--text-lg); margin-bottom: var(--space-2); }
.env-card p { font-size: var(--text-sm); color: var(--color-text-muted); margin-bottom: var(--space-4); }
.env-meta { display: flex; flex-wrap: wrap; gap: var(--space-2); border-top: 1px solid var(--color-border); padding-top: var(--space-4); }
.env-tag { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-text-faint); }
.env-tag b { color: var(--color-text-muted); font-weight: 500; }

/* feature list rows */
.feat { display: grid; gap: var(--space-5); }
.feat-row { display: grid; grid-template-columns: 44px 1fr; gap: var(--space-4); padding: var(--space-5) 0; border-top: 1px solid var(--color-border); }
.feat-row .ico { width: 44px; height: 44px; border-radius: var(--radius-md); border: 1px solid var(--color-border); display: grid; place-items: center; color: var(--color-primary); }
.feat-row .ico svg { width: 20px; height: 20px; }
.feat-row h3 { font-size: var(--text-base); font-weight: 600; margin-bottom: var(--space-1); }
.feat-row p { font-size: var(--text-sm); color: var(--color-text-muted); max-width: 64ch; }

/* CTA band */
.cta-band { border: 1px solid var(--color-border); border-radius: var(--radius-xl); padding: clamp(var(--space-8), 4vw, var(--space-12)); text-align: center; background: linear-gradient(180deg, var(--color-surface) 0%, var(--color-bg-2) 100%); position: relative; overflow: hidden; }
.cta-band::after { content: ''; position: absolute; inset: 0; background: radial-gradient(60% 100% at 50% 0%, rgba(47,212,207,0.1), transparent 60%); pointer-events: none; }
.cta-band h2 { font-size: var(--text-2xl); position: relative; }
.cta-band p { margin: var(--space-4) auto var(--space-6); position: relative; }
.cta-band .btn-row { justify-content: center; position: relative; }

/* footer */
.site-footer { border-top: 1px solid var(--color-border); padding-block: var(--space-10) var(--space-6); background: var(--color-bg-2); }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: var(--space-8); }
.footer-grid h4 { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-text-faint); font-weight: 500; margin-bottom: var(--space-4); }
.footer-grid a { display: block; font-size: var(--text-sm); color: var(--color-text-muted); padding: var(--space-1) 0; }
.footer-grid a:hover { color: var(--color-primary); }
.footer-bottom { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: var(--space-4); margin-top: var(--space-8); padding-top: var(--space-5); border-top: 1px solid var(--color-border); font-size: var(--text-xs); color: var(--color-text-faint); font-family: var(--font-mono); }

/* forms */
.form-card { border: 1px solid var(--color-border); border-radius: var(--radius-xl); padding: clamp(var(--space-6), 4vw, var(--space-10)); background: var(--color-surface); }
.form-card .form-tag { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-primary); }
.form-card h3 { font-size: var(--text-xl); margin: var(--space-3) 0 var(--space-2); }
.form-card > p { font-size: var(--text-sm); color: var(--color-text-muted); margin-bottom: var(--space-6); }
.field { margin-bottom: var(--space-4); }
.field label { display: block; font-size: var(--text-xs); font-family: var(--font-mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--color-text-muted); margin-bottom: var(--space-2); }
.field input, .field textarea, .field select {
  width: 100%; background: var(--color-bg-2); border: 1px solid var(--color-border);
  border-radius: var(--radius-md); padding: 0.7rem 0.85rem; font-size: var(--text-sm); color: var(--color-text);
}
.field input::placeholder, .field textarea::placeholder { color: var(--color-text-faint); }
.field input:focus, .field textarea:focus, .field select:focus { border-color: var(--color-primary-line); outline: none; box-shadow: 0 0 0 3px var(--color-primary-dim); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
.form-note { font-size: var(--text-xs); color: var(--color-text-faint); margin-top: var(--space-4); line-height: 1.5; }

/* node motif (decorative svg container) */
.node-art { width: 100%; height: 100%; }

/* compliance / note callout */
.note-box { border: 1px solid var(--color-border); border-left: 2px solid var(--color-primary); border-radius: var(--radius-md); padding: var(--space-5) var(--space-6); background: var(--color-surface); }
.note-box p { font-size: var(--text-sm); color: var(--color-text-muted); }

/* reveal animation */
[data-reveal] { opacity: 0; transform: translateY(16px); transition: opacity 0.7s cubic-bezier(0.16,1,0.3,1), transform 0.7s cubic-bezier(0.16,1,0.3,1); }
[data-reveal].in { opacity: 1; transform: none; }

/* page hero (interior) */
.page-hero { padding-block: clamp(var(--space-10), 6vw, var(--space-16)) var(--space-8); position: relative; overflow: hidden; }
.page-hero::after { content: ''; position: absolute; inset: 0; background: radial-gradient(50% 60% at 80% 0%, rgba(47,212,207,0.08), transparent 60%); pointer-events: none; }
.page-hero .wrap { position: relative; z-index: 1; }
.page-hero h1 { font-size: var(--text-2xl); margin: var(--space-4) 0 var(--space-5); }
.page-hero .lead { font-size: var(--text-lg); }

/* two-col content */
.cols-2 { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(var(--space-8), 5vw, var(--space-16)); align-items: start; }

/* spec list */
.spec-list { list-style: none; display: grid; gap: 0; }
.spec-list li { display: grid; grid-template-columns: 1fr auto; gap: var(--space-4); padding: var(--space-3) 0; border-bottom: 1px solid var(--color-border); font-size: var(--text-sm); }
.spec-list li span:first-child { color: var(--color-text-muted); }
.spec-list li span:last-child { font-family: var(--font-mono); color: var(--color-text); font-size: var(--text-xs); text-align: right; }

/* ===================== responsive ===================== */
@media (max-width: 900px) {
  .grid-3, .grid-4, .env-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-8); }
  .split, .cols-2 { grid-template-columns: 1fr; }
  .stat-strip { grid-template-columns: repeat(2, 1fr); gap: var(--space-8); }
}
@media (max-width: 720px) {
  .nav-links { display: none; }
  .menu-btn { display: grid; }
  .nav-links.open {
    display: flex; flex-direction: column; align-items: stretch;
    position: absolute; top: 68px; left: 0; right: 0;
    background: var(--color-bg); border-bottom: 1px solid var(--color-border);
    padding: var(--space-4); gap: var(--space-1);
  }
  .nav-links.open a { padding: var(--space-3); }
}
@media (max-width: 560px) {
  .grid-2, .grid-3, .grid-4, .env-grid, .field-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .brand small { display: none; }
}