/* EquivalentTo design system — premium AI-product aesthetic, zero runtime deps.
   Tokens, dark/light, glassmorphism, typography, layout. Ships ~9KB. */
:root {
  --bg: #f7f8fc; --bg-elev: #ffffff; --bg-soft: #eef1f8;
  --text: #0c1024; --text-dim: #4a5170; --text-faint: #7b82a0;
  --border: #e3e7f2; --border-strong: #cdd4e6;
  --brand: #4f46e5; --brand-2: #7c3aed; --brand-3: #0ea5e9;
  --accent: #06b6d4; --good: #12a150; --warn: #d97706; --bad: #dc2626;
  --ring: rgba(79,70,229,.35);
  --shadow-sm: 0 1px 2px rgba(16,20,40,.06), 0 1px 3px rgba(16,20,40,.05);
  --shadow-md: 0 4px 20px rgba(16,20,40,.08);
  --shadow-lg: 0 20px 60px rgba(16,20,40,.14);
  --glass: rgba(255,255,255,.66); --glass-brd: rgba(255,255,255,.5);
  --radius: 14px; --radius-lg: 22px;
  --maxw: 1140px;
  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  --grad: linear-gradient(120deg, var(--brand), var(--brand-2) 55%, var(--brand-3));
}
:root[data-theme="dark"] {
  --bg: #070a16; --bg-elev: #0e1326; --bg-soft: #131a33;
  --text: #eef1fb; --text-dim: #aab2d4; --text-faint: #7982a8;
  --border: #1f2745; --border-strong: #2c3660;
  --brand: #7c8bff; --brand-2: #a78bfa; --brand-3: #38bdf8;
  --ring: rgba(124,139,255,.4);
  --shadow-sm: 0 1px 2px rgba(0,0,0,.4);
  --shadow-md: 0 6px 24px rgba(0,0,0,.5);
  --shadow-lg: 0 24px 70px rgba(0,0,0,.6);
  --glass: rgba(14,19,38,.6); --glass-brd: rgba(124,139,255,.16);
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { animation-duration: .001ms !important; transition-duration: .001ms !important; } }
body {
  margin: 0; font-family: var(--font); color: var(--text); background: var(--bg);
  line-height: 1.65; font-size: 17px; -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
body::before {
  content: ""; position: fixed; inset: 0; z-index: -2; pointer-events: none;
  background:
    radial-gradient(60rem 40rem at 12% -8%, color-mix(in oklab, var(--brand) 22%, transparent), transparent 60%),
    radial-gradient(50rem 40rem at 95% 0%, color-mix(in oklab, var(--brand-3) 18%, transparent), transparent 55%);
}
body::after {
  content: ""; position: fixed; inset: 0; z-index: -2; pointer-events: none; opacity: .5;
  background-image: linear-gradient(var(--border) 1px, transparent 1px), linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 48px 48px; -webkit-mask-image: radial-gradient(70% 55% at 50% 0%, #000, transparent 75%);
          mask-image: radial-gradient(70% 55% at 50% 0%, #000, transparent 75%);
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
h1, h2, h3 { line-height: 1.15; letter-spacing: -.02em; font-weight: 700; }
h1 { font-size: clamp(2rem, 4.5vw, 3.3rem); margin: .2em 0 .3em; }
h2 { font-size: clamp(1.4rem, 2.6vw, 2rem); margin: 1.8em 0 .5em; }
h3 { font-size: 1.2rem; margin: 1.4em 0 .4em; }
p { color: var(--text-dim); }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
.narrow { max-width: 820px; }

/* nav */
.nav { position: sticky; top: 0; z-index: 50; backdrop-filter: saturate(160%) blur(14px);
  background: var(--glass); border-bottom: 1px solid var(--border); }
.nav-inner { display: flex; align-items: center; gap: 20px; height: 62px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: -.02em; color: var(--text); font-size: 1.15rem; }
.brand-mark { width: 30px; height: 30px; border-radius: 9px; background: var(--grad); box-shadow: var(--shadow-sm); display: grid; place-items: center; color: #fff; font-weight: 900; }
.nav-links { display: flex; gap: 6px; margin-left: 8px; }
.nav-links a { color: var(--text-dim); padding: 7px 12px; border-radius: 9px; font-size: .93rem; font-weight: 500; }
.nav-links a:hover { color: var(--text); background: var(--bg-soft); text-decoration: none; }
.nav-spacer { flex: 1; }
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 9px 16px; border-radius: 10px;
  font-weight: 600; font-size: .93rem; border: 1px solid var(--border-strong); background: var(--bg-elev); color: var(--text); cursor: pointer; transition: transform .12s, box-shadow .12s; }
.btn:hover { text-decoration: none; box-shadow: var(--shadow-md); transform: translateY(-1px); }
.btn-primary { background: var(--grad); color: #fff; border: none; }
.btn-ghost { background: transparent; }
.kbd { font-family: var(--mono); font-size: .78rem; padding: 2px 6px; border-radius: 6px; border: 1px solid var(--border-strong); background: var(--bg-soft); color: var(--text-faint); }

/* cards / glass */
.card { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow-sm); }
.glass { background: var(--glass); border: 1px solid var(--glass-brd); backdrop-filter: blur(12px); border-radius: var(--radius-lg); }
.pad { padding: 22px; } .pad-lg { padding: 30px; }

/* hero */
.hero { padding: 72px 0 40px; text-align: center; }
.badge { display: inline-flex; align-items: center; gap: 8px; padding: 6px 14px; border-radius: 999px;
  background: var(--bg-elev); border: 1px solid var(--border); font-size: .82rem; color: var(--text-dim); font-weight: 500; box-shadow: var(--shadow-sm); }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--good); box-shadow: 0 0 0 4px color-mix(in oklab, var(--good) 25%, transparent); }
.gradient-text { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lede { font-size: 1.2rem; color: var(--text-dim); max-width: 680px; margin: 0 auto 26px; }

/* grid */
.grid { display: grid; gap: 18px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 860px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } .nav-links { display: none; } }

/* stat */
.stat { text-align: center; }
.stat .num { font-size: 2.3rem; font-weight: 800; letter-spacing: -.03em; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.stat .lbl { color: var(--text-faint); font-size: .9rem; }

/* answer box (the money element for AI/voice search) */
.answer-box { border-left: 4px solid var(--brand); background: color-mix(in oklab, var(--brand) 8%, var(--bg-elev)); border-radius: 12px; padding: 20px 24px; margin: 24px 0; }
.answer-box .k { font-size: .8rem; text-transform: uppercase; letter-spacing: .08em; color: var(--brand); font-weight: 700; }
.answer-box .v { font-size: 1.35rem; font-weight: 700; margin-top: 4px; color: var(--text); }

/* tables */
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius); }
table.data { width: 100%; border-collapse: collapse; font-size: .95rem; }
table.data th, table.data td { padding: 12px 16px; text-align: left; border-bottom: 1px solid var(--border); }
table.data thead th { background: var(--bg-soft); font-size: .82rem; text-transform: uppercase; letter-spacing: .05em; color: var(--text-faint); }
table.data tbody tr:hover { background: var(--bg-soft); }
.delta-up { color: var(--bad); font-weight: 600; } .delta-down { color: var(--good); font-weight: 600; }

/* calculator */
.calc { display: grid; gap: 14px; }
.calc-row { display: grid; grid-template-columns: 1fr auto; gap: 12px; align-items: center; }
.field label { font-size: .82rem; color: var(--text-faint); font-weight: 600; display: block; margin-bottom: 5px; }
.field input, .field select { width: 100%; padding: 11px 13px; border-radius: 10px; border: 1px solid var(--border-strong); background: var(--bg); color: var(--text); font: inherit; font-size: 1rem; }
.field input:focus, .field select:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 4px var(--ring); }

/* faq */
.faq details { border: 1px solid var(--border); border-radius: 12px; padding: 4px 18px; margin: 10px 0; background: var(--bg-elev); }
.faq summary { cursor: pointer; font-weight: 600; padding: 12px 0; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--brand); font-size: 1.3rem; }
.faq details[open] summary::after { content: "−"; }
.faq details[open] summary { border-bottom: 1px solid var(--border); }
.faq p { padding: 12px 0; margin: 0; }

/* chips / pills */
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip { display: inline-flex; align-items: center; gap: 6px; padding: 6px 12px; border-radius: 999px; background: var(--bg-elev); border: 1px solid var(--border); font-size: .86rem; color: var(--text-dim); }
.chip:hover { border-color: var(--brand); color: var(--text); text-decoration: none; }

/* breadcrumb */
.crumbs { display: flex; flex-wrap: wrap; gap: 6px; font-size: .86rem; color: var(--text-faint); padding: 18px 0 4px; }
.crumbs a { color: var(--text-faint); }
.crumbs a:hover { color: var(--brand); }

/* author box */
.author { display: flex; gap: 14px; align-items: flex-start; }
.avatar { width: 46px; height: 46px; border-radius: 50%; background: var(--grad); display: grid; place-items: center; color: #fff; font-weight: 800; flex: none; }

/* section spacing */
.section { padding: 34px 0; }
.eyebrow { text-transform: uppercase; letter-spacing: .1em; font-size: .78rem; font-weight: 700; color: var(--brand); }
.prose p { margin: 1em 0; } .prose ul { color: var(--text-dim); }

/* footer */
.footer { margin-top: 60px; border-top: 1px solid var(--border); background: var(--bg-elev); padding: 46px 0 30px; }
.footer h4 { font-size: .82rem; text-transform: uppercase; letter-spacing: .08em; color: var(--text-faint); margin: 0 0 12px; }
.footer a { color: var(--text-dim); font-size: .92rem; display: block; padding: 3px 0; }
.footer a:hover { color: var(--brand); }

/* fade-in on scroll (progressive; no JS required for content) */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; } }

/* command palette */
.cmdk-overlay { position: fixed; inset: 0; background: rgba(6,9,20,.5); backdrop-filter: blur(4px); z-index: 100; display: none; align-items: flex-start; justify-content: center; padding-top: 12vh; }
.cmdk-overlay.open { display: flex; }
.cmdk { width: min(620px, 92vw); background: var(--bg-elev); border: 1px solid var(--border-strong); border-radius: 16px; box-shadow: var(--shadow-lg); overflow: hidden; }
.cmdk input { width: 100%; padding: 18px 20px; border: none; border-bottom: 1px solid var(--border); background: transparent; color: var(--text); font: inherit; font-size: 1.05rem; }
.cmdk input:focus { outline: none; }
.cmdk-results { max-height: 52vh; overflow-y: auto; }
.cmdk-item { display: block; padding: 12px 20px; border-bottom: 1px solid var(--border); color: var(--text); }
.cmdk-item:hover, .cmdk-item.active { background: var(--bg-soft); text-decoration: none; }
.cmdk-item .t { font-weight: 600; } .cmdk-item .s { font-size: .82rem; color: var(--text-faint); }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.skip { position: absolute; left: -999px; top: 8px; background: var(--brand); color: #fff; padding: 8px 14px; border-radius: 8px; z-index: 200; }
.skip:focus { left: 8px; }
:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; border-radius: 4px; }