/* Matrix Calc. — marketing site. One accent colour, dark surface, sparse chrome. */

:root {
  --bg: #0a0c10;
  --bg-elev: #12151d;
  --bg-alt: #0d1016;
  --border: #232936;
  --text: #e9ecf1;
  --muted: #949daf;
  --accent: #c4433c;
  --accent-hover: #d6554e;
  --accent-soft: rgba(196, 67, 60, 0.14);
  --radius: 14px;
  --wrap: 1120px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Inter, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

h1, h2, h3 { margin: 0; line-height: 1.15; letter-spacing: -0.02em; }

p { margin: 0; }

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

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  background: var(--accent-soft);
  color: #f0b4b0;
  padding: 1px 5px;
  border-radius: 5px;
}

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
}

.wrap--narrow { max-width: 760px; }

/* ---------- nav ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(10, 12, 16, 0.82);
  backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav__inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 650;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand img { border-radius: 7px; }

.nav__links {
  display: flex;
  gap: 26px;
  margin-left: auto;
  font-size: 15px;
  color: var(--muted);
}

.nav__links a:hover { color: var(--text); }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font: inherit;
  font-weight: 600;
  padding: 12px 22px;
  border-radius: 10px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background-color .16s ease, border-color .16s ease, color .16s ease;
  white-space: nowrap;
}

.btn--sm { padding: 9px 16px; font-size: 14px; }

.btn--primary { background: var(--accent); color: #fff; }
.btn--primary:hover { background: var(--accent-hover); }

.btn--ghost {
  background: transparent;
  border-color: #333c4d;
  color: var(--text);
}
.btn--ghost:hover { border-color: #46516a; background: rgba(255,255,255,0.03); }

.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.cta-row--center { justify-content: center; }

/* ---------- hero ---------- */

.hero { padding: 84px 0 72px; }

.hero__grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  align-items: center;
  gap: 56px;
}

.eyebrow {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--accent-hover);
  margin-bottom: 16px;
}

.hero h1 {
  font-size: clamp(2.1rem, 5.2vw, 3.4rem);
  font-weight: 700;
  margin-bottom: 20px;
}

.lede {
  font-size: clamp(1.02rem, 1.6vw, 1.16rem);
  color: var(--muted);
  max-width: 34em;
}

.note { margin-top: 18px; font-size: 14px; color: var(--muted); }

.hero__shot {
  position: relative;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg-elev);
  box-shadow: 0 26px 70px -30px rgba(196, 67, 60, 0.45), 0 10px 40px -20px rgba(0,0,0,0.9);
}

/* ---------- sections ---------- */

.section { padding: 76px 0; }

.section--alt { background: var(--bg-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }

.section__title {
  font-size: clamp(1.5rem, 3vw, 2.05rem);
  font-weight: 680;
  margin-bottom: 40px;
  max-width: 22em;
}

/* ---------- feature cards ---------- */

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(268px, 1fr));
  gap: 20px;
}

.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 24px;
}

.card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--accent-soft);
  color: var(--accent-hover);
  margin-bottom: 18px;
}

.card__icon svg { width: 21px; height: 21px; }

.card h3 { font-size: 1.06rem; font-weight: 640; margin-bottom: 9px; }

.card p { color: var(--muted); font-size: 0.95rem; }

/* ---------- screenshots ---------- */

.shots {
  display: grid;
  grid-template-columns: 1.55fr 1fr;
  gap: 28px;
  align-items: start;
}

.shot { margin: 0; }

.shot img {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-elev);
}

.shot figcaption {
  margin-top: 14px;
  font-size: 14px;
  color: var(--muted);
}

.shot--phone img { margin: 0 auto; max-width: 300px; }
.shot--phone figcaption { text-align: center; }

/* ---------- faq ---------- */

.faq { border-top: 1px solid var(--border); }

.faq details { border-bottom: 1px solid var(--border); }

.faq summary {
  cursor: pointer;
  list-style: none;
  padding: 20px 34px 20px 0;
  position: relative;
  font-weight: 600;
}

.faq summary::-webkit-details-marker { display: none; }

.faq summary::after {
  content: "+";
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 22px;
  font-weight: 400;
  color: var(--muted);
  transition: transform .18s ease;
}

.faq details[open] summary::after { content: "−"; }

.faq details p {
  color: var(--muted);
  padding: 0 40px 22px 0;
  font-size: 0.96rem;
}

/* ---------- closing band ---------- */

.band { padding: 84px 0; border-top: 1px solid var(--border); }

.band__inner { text-align: center; }

.band h2 { font-size: clamp(1.7rem, 3.6vw, 2.4rem); font-weight: 700; }

.band p { color: var(--muted); margin-top: 12px; }

/* ---------- footer ---------- */

.footer { border-top: 1px solid var(--border); padding: 40px 0 32px; background: var(--bg-alt); }

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.footer__brand {
  display: flex;
  align-items: center;
  gap: 9px;
  font-weight: 620;
}

.footer__brand img { border-radius: 6px; }

.footer__links { display: flex; gap: 24px; flex-wrap: wrap; font-size: 15px; color: var(--muted); }
.footer__links a:hover { color: var(--text); }

.footer__legal { margin-top: 28px; font-size: 13.5px; color: var(--muted); }

/* ---------- responsive ---------- */

@media (max-width: 900px) {
  .hero { padding: 56px 0 48px; }
  .hero__grid { grid-template-columns: 1fr; gap: 40px; }
  .lede { max-width: none; }
  .shots { grid-template-columns: 1fr; gap: 36px; }
  .hero__shot { max-width: 320px; margin: 0 auto; }
}

@media (max-width: 720px) {
  .nav__links { display: none; }
  .nav__inner { justify-content: space-between; }
  .nav__inner .btn--primary { margin-left: auto; }
  .section { padding: 60px 0; }
  .section__title { margin-bottom: 32px; }
}

@media (max-width: 420px) {
  .wrap { padding: 0 18px; }
  .btn { width: 100%; }
  .cta-row .btn { width: 100%; }
  .nav .btn--sm { width: auto; }
}