/* Voltbench — editorial design system
   Fashion-editorial treatment (per reference): high-contrast serif display,
   generous whitespace, floating info card, soft pastel category columns.
   Committed light theme by design. No JS dependency. */

@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:ital,wght@0,400;0,600;0,700;0,900;1,400;1,600;1,900&display=swap');

:root{
  --bg:#f5f3ef;         /* warm gallery white */
  --surface:#ffffff;
  --ink:#161616;        /* near-black */
  --fg:#161616;
  --muted:#6d6a64;
  --line:#e4e0d9;
  --line-strong:#cfcabf;
  /* soft, sophisticated pastels (category columns) */
  --c-teal:#cfe0dc;
  --c-sand:#eae1cf;
  --c-sage:#d4dcb6;
  --c-rose:#f1d7d9;
  /* semantic */
  --good:#2f6b46;
  --good-soft:#e2efe6;
  --bad:#9e2a22;
  --bad-soft:#f6e2df;

  --serif:"Playfair Display",Georgia,"Times New Roman",serif;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --radius:6px;
  --wrap:1160px;
  --shadow:0 2px 8px rgba(22,22,22,.06);
  --shadow-lg:0 18px 50px rgba(22,22,22,.16);
}

*{box-sizing:border-box}
html{scroll-behavior:smooth;color-scheme:light}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important;animation:none!important}}
body{margin:0;background:var(--bg);color:var(--ink);
  font:16px/1.65 var(--sans);-webkit-font-smoothing:antialiased;letter-spacing:.005em}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 32px}
@media (max-width:640px){.wrap{padding:0 22px}}
a{color:var(--ink)}
h1,h2,h3{margin:0;line-height:1.08;text-wrap:balance}

/* hide the deprecated theme toggle from the old design */
#theme-toggle{display:none!important}

/* small uppercase label */
.kicker{font-family:var(--sans);font-size:.7rem;font-weight:700;letter-spacing:.24em;
  text-transform:uppercase;color:var(--muted)}

/* ---------- Header ---------- */
.site-header{background:var(--bg);border-bottom:1px solid var(--line)}
.site-header .nav{display:flex;align-items:center;justify-content:space-between;height:74px}
.brand{display:flex;align-items:center;gap:10px;font-family:var(--sans);font-weight:800;
  font-size:1.15rem;letter-spacing:.16em;text-transform:uppercase;color:var(--ink)}
.brand:hover{text-decoration:none;color:var(--ink)}
.brand .bolt{display:grid;place-items:center;width:24px;height:24px;border-radius:50%;
  background:var(--ink);color:var(--bg);font-family:var(--serif);font-weight:700;font-size:.85rem;letter-spacing:0}
.site-header nav{display:flex;gap:34px;align-items:center}
.site-header nav a{font-family:var(--sans);color:var(--ink);font-size:.82rem;font-weight:600;
  letter-spacing:.06em;text-transform:uppercase}
.site-header nav a:hover{text-decoration:none;color:var(--muted)}
@media (max-width:640px){.site-header nav{gap:18px}.site-header nav a{font-size:.72rem}}

/* ---------- Hero ---------- */
.hero{border-bottom:1px solid var(--line);background:linear-gradient(180deg,#faf9f6,var(--bg))}
.hero .wrap{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center;
  min-height:520px;padding:56px 32px 64px}
.hero-copy .eyebrow{margin-bottom:22px}
.display{font-family:var(--serif);font-weight:900;color:var(--ink);
  font-size:clamp(3rem,7vw,5.4rem);line-height:.98;letter-spacing:-.01em}
.display .ital{display:block;font-weight:400;font-style:italic;font-size:.82em;
  margin-top:.02em;letter-spacing:0}
.hero-tag{font-family:var(--serif);font-style:italic;font-size:1.32rem;color:var(--muted);
  margin:26px 0 0;max-width:34ch}
.hero-tag b{font-weight:700;font-style:italic;color:var(--ink)}

/* hero visual panel + floating card */
.hero-visual{position:relative;min-height:420px;border-radius:10px;overflow:hidden;
  background:radial-gradient(120% 120% at 20% 10%,#e9e6df,#d9d5cc 70%,#cbc7bd);
  box-shadow:var(--shadow)}
.hero-visual svg{position:absolute;inset:0;width:100%;height:100%}
.hero-card{position:absolute;right:22px;bottom:22px;width:min(300px,72%);background:var(--surface);
  padding:26px 26px 24px;border-radius:8px;box-shadow:var(--shadow-lg)}
.hero-card h2{font-family:var(--serif);font-weight:700;font-size:1.15rem;margin:10px 0 10px;line-height:1.2}
.hero-card p{font-size:.86rem;color:var(--muted);margin:0 0 18px;line-height:1.55}
.arrow{display:inline-grid;place-items:center;width:44px;height:44px;border-radius:50%;
  background:var(--ink);color:var(--bg);font-size:1.1rem;transition:transform .18s ease}
.arrow:hover{text-decoration:none;color:var(--bg);transform:translateX(4px)}
@media (max-width:860px){
  .hero .wrap{grid-template-columns:1fr;gap:32px;min-height:0;padding:44px 22px 52px}
  .hero-visual{min-height:300px}
}

/* ---------- Category columns (pastel) ---------- */
.cats{display:grid;grid-template-columns:repeat(4,1fr)}
.cat{position:relative;padding:44px 30px 40px;display:flex;flex-direction:column;
  min-height:340px;color:var(--ink)}
.cat + .cat{border-left:1px solid rgba(22,22,22,.06)}
.cat.teal{background:var(--c-teal)} .cat.sand{background:var(--c-sand)}
.cat.sage{background:var(--c-sage)} .cat.rose{background:var(--c-rose)}
.cat h3{font-family:var(--serif);font-weight:700;font-size:1.5rem;letter-spacing:.01em;margin:0 0 4px}
.cat .num{font-family:var(--sans);font-size:.7rem;font-weight:700;letter-spacing:.2em;
  text-transform:uppercase;color:rgba(22,22,22,.5);margin-bottom:16px}
.cat p{font-size:.9rem;line-height:1.6;color:rgba(22,22,22,.78);margin:0 0 24px}
.cat .btn-dark{margin-top:auto}
.btn-dark{align-self:flex-start;display:inline-block;background:var(--ink);color:#fff;
  font-family:var(--sans);font-size:.72rem;font-weight:700;letter-spacing:.1em;text-transform:uppercase;
  padding:11px 20px;border-radius:3px;transition:background .16s}
.btn-dark:hover{text-decoration:none;color:#fff;background:#000}
.btn-dark[aria-disabled="true"]{background:transparent;color:rgba(22,22,22,.55);
  border:1px solid rgba(22,22,22,.35);cursor:default;pointer-events:none}
@media (max-width:860px){.cats{grid-template-columns:1fr 1fr}
  .cat:nth-child(odd){border-left:0}.cat{border-top:1px solid rgba(22,22,22,.06)}}
@media (max-width:520px){.cats{grid-template-columns:1fr}.cat{min-height:0;border-left:0}}

/* ---------- Generic section ---------- */
.section{padding:70px 0}
.section-head{max-width:66ch;margin:0 auto 40px;text-align:center}
.section-head h2{font-family:var(--serif);font-weight:700;font-size:2rem;margin:12px 0 12px}
.section-head p{color:var(--muted);margin:0}

/* ---------- Tool page ---------- */
.breadcrumb{font-family:var(--sans);font-size:.74rem;letter-spacing:.08em;text-transform:uppercase;
  color:var(--muted);padding:28px 0 0}
.breadcrumb a{color:var(--muted)}
.tool-head{padding:16px 0 2px;max-width:64ch}
.tool-head .kicker{margin-bottom:14px;display:block}
.tool-head h1{font-family:var(--serif);font-weight:900;font-size:clamp(2.1rem,4.2vw,3rem);
  line-height:1.02;margin:6px 0 16px}
.tool-head .sub{font-family:var(--serif);font-style:italic;color:var(--muted);font-size:1.2rem;margin:0;max-width:60ch}

.calc{background:var(--surface);border:1px solid var(--line);border-radius:8px;
  padding:30px;box-shadow:var(--shadow);margin:30px 0 10px}
.grid{display:grid;grid-template-columns:1fr 1fr;gap:20px}
@media (max-width:540px){.grid{grid-template-columns:1fr}}
label{display:block;font-family:var(--sans);font-size:.68rem;font-weight:700;letter-spacing:.12em;
  text-transform:uppercase;color:var(--muted);margin-bottom:8px}
input,select{width:100%;padding:12px 13px;border:1px solid var(--line-strong);border-radius:4px;
  background:#fff;color:var(--ink);font-size:1rem;font-family:var(--sans);
  transition:border-color .15s,box-shadow .15s}
input:focus,select:focus{outline:none;border-color:var(--ink);box-shadow:0 0 0 3px rgba(22,22,22,.08)}

/* result panel — editorial: big serif number */
.result{margin-top:26px;background:#fbfaf7;border:1px solid var(--line);border-top:3px solid var(--ink);
  border-radius:8px;padding:26px 28px}
.result .rk{font-family:var(--sans);font-size:.68rem;letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.result .big{font-family:var(--serif);font-weight:900;font-size:2.7rem;color:var(--ink);
  line-height:1.05;letter-spacing:-.01em;margin:8px 0 14px}
.result .row{display:flex;justify-content:space-between;gap:12px;font-family:var(--sans);font-size:.9rem;
  padding:9px 0;border-top:1px solid var(--line);color:var(--muted)}
.result .row span:last-child{color:var(--ink);font-variant-numeric:tabular-nums;font-weight:600}
.result .note{color:var(--muted);font-size:.86rem;font-family:var(--sans)}
.pill{display:inline-block;padding:3px 11px;border-radius:3px;font-family:var(--sans);font-size:.64rem;
  font-weight:700;letter-spacing:.1em;text-transform:uppercase;vertical-align:middle}
.pill.good{background:var(--good-soft);color:var(--good)}
.pill.bad{background:var(--bad-soft);color:var(--bad)}

/* prose / education */
.prose{max-width:70ch}
.prose h2{font-family:var(--serif);font-weight:700;font-size:1.5rem;margin:46px 0 14px}
.prose .formula{font-family:var(--serif);font-style:italic;text-align:center;font-size:1.15rem;
  background:#fbfaf7;border:1px solid var(--line);border-radius:6px;padding:16px;margin:16px 0;color:var(--ink)}
table{border-collapse:collapse;width:100%;font-family:var(--sans);font-size:.86rem;margin:14px 0;
  border:1px solid var(--line);border-radius:6px;overflow:hidden}
th,td{border-bottom:1px solid var(--line);padding:10px 12px;text-align:right;font-variant-numeric:tabular-nums}
th{background:#f0ede7;font-weight:700}
th:first-child,td:first-child{text-align:left}
.tbl-scroll{overflow-x:auto}
.note{font-size:.87rem;color:var(--muted)}
details{border:1px solid var(--line);border-radius:6px;padding:14px 18px;margin:10px 0;background:var(--surface)}
summary{cursor:pointer;font-weight:600}
summary::marker{color:var(--ink)}
.disclaimer{margin:40px 0;padding:18px 20px;border-left:3px solid var(--ink);background:#fbfaf7;
  border-radius:0 6px 6px 0;font-size:.9rem;color:var(--ink)}

/* ---------- Footer ---------- */
.site-footer{border-top:1px solid var(--line);margin-top:0;padding:44px 0;color:var(--muted);
  font-size:.86rem;background:var(--bg)}
.site-footer .cols{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap;align-items:center}
.site-footer a{color:var(--muted)}
.site-footer .brand-sm{font-family:var(--sans);color:var(--ink);font-weight:800;
  letter-spacing:.14em;text-transform:uppercase}