/* =========================================================
   OnSystem Landing Page
   Simple responsive CSS - no framework required
   ========================================================= */

:root {
  --bg: #07111f;
  --panel: #0d1a2b;
  --panel-2: #10233a;
  --text: #edf4fb;
  --muted: #9fb0c3;
  --line: rgba(255,255,255,0.10);
  --accent: #5bb8ff;
  --accent-2: #8be0c0;
  --white: #ffffff;
  --light-bg: #f4f7fa;
  --dark-text: #16202d;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

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

.container {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

/* HEADER */
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(7, 17, 31, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}

.nav {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 1.6px;
}

.brand span {
  color: var(--accent);
}

nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

nav a {
  color: var(--muted);
  font-size: 14px;
}

nav a:hover {
  color: var(--white);
}

.nav-button {
  border: 1px solid var(--line);
  padding: 9px 15px;
  border-radius: 10px;
}

/* HERO */
.hero {
  min-height: 690px;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  background: rgba(91, 184, 255, 0.10);
  filter: blur(10px);
  right: -180px;
  top: 20px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 70px;
  align-items: center;
  position: relative;
}

.eyebrow {
  color: var(--accent-2);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 2px;
  margin-bottom: 14px;
}

h1 {
  margin: 0;
  font-size: clamp(48px, 7vw, 82px);
  line-height: 0.98;
  letter-spacing: -3px;
}

.lead {
  max-width: 680px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.lead.sq {
  margin-top: 10px;
  font-size: 16px;
}

.hero-actions {
  margin-top: 34px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 20px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 14px;
}

.primary {
  background: var(--accent);
  color: #06111d;
}

.secondary {
  border: 1px solid var(--line);
  color: var(--white);
}

.hero-panel {
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 26px;
  box-shadow: 0 24px 70px rgba(0,0,0,0.25);
}

.panel-label {
  color: var(--muted);
  font-size: 11px;
  letter-spacing: 1.5px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--line);
}

.metric {
  display: flex;
  gap: 18px;
  align-items: center;
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.metric span {
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
}

.metric strong {
  font-size: 18px;
}

.panel-note {
  margin-top: 22px;
  color: var(--accent-2);
  font-size: 13px;
}

/* COMMON SECTION */
.section {
  padding: 100px 0;
}

.section-heading {
  max-width: 720px;
  margin-bottom: 44px;
}

h2 {
  margin: 0;
  font-size: clamp(34px, 4vw, 54px);
  line-height: 1.08;
  letter-spacing: -1.8px;
}

.section-heading p,
.about-text p,
.contact p {
  color: var(--muted);
  font-size: 17px;
}

/* CARDS */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 28px;
  position: relative;
  min-height: 520px;
  display: flex;
  flex-direction: column;
}

.card.featured {
  background: linear-gradient(180deg, #10243a, #0d1a2b);
}

.card-number {
  color: var(--accent);
  font-size: 12px;
  font-weight: 800;
  margin-bottom: 18px;
}

.badge {
  align-self: flex-start;
  color: #06111d;
  background: var(--accent-2);
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 800;
  margin-bottom: 24px;
}

.badge.muted {
  color: var(--text);
  background: rgba(255,255,255,0.08);
}

.card h3 {
  font-size: 25px;
  margin: 0 0 14px;
}

.card p {
  color: var(--muted);
}

.card ul {
  padding-left: 18px;
  color: #c7d4e0;
}

.card li {
  margin: 8px 0;
}

.card-footer {
  margin-top: auto;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 12px;
}

/* LIGHT SECTION */
.alt {
  background: var(--light-bg);
  color: var(--dark-text);
}

.alt .eyebrow {
  color: #237e68;
}

.alt .about-text p {
  color: #5d6875;
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: start;
}

/* CONTACT */
.contact-box {
  display: grid;
  grid-template-columns: 1fr 0.8fr;
  gap: 70px;
  align-items: center;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 46px;
}

.contact-details {
  border-left: 1px solid var(--line);
  padding-left: 36px;
}

.contact-row {
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.contact-row span {
  display: block;
  color: var(--muted);
  font-size: 12px;
  margin-bottom: 4px;
}

.contact-row strong {
  font-size: 17px;
}

/* FOOTER */
footer {
  border-top: 1px solid var(--line);
}

.footer-row {
  min-height: 88px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--muted);
  font-size: 13px;
}

.brand.small {
  font-size: 16px;
}

/* MOBILE */
@media (max-width: 900px) {
  .hero {
    min-height: auto;
    padding: 90px 0 70px;
  }

  .hero-grid,
  .about-grid,
  .contact-box {
    grid-template-columns: 1fr;
  }

  .cards {
    grid-template-columns: 1fr;
  }

  .contact-details {
    border-left: 0;
    border-top: 1px solid var(--line);
    padding-left: 0;
    padding-top: 20px;
  }

  .card {
    min-height: auto;
  }
}

@media (max-width: 650px) {
  .container {
    width: min(100% - 26px, 1120px);
  }

  nav a:not(.nav-button) {
    display: none;
  }

  h1 {
    letter-spacing: -2px;
  }

  .section {
    padding: 72px 0;
  }

  .contact-box {
    padding: 28px;
  }

  .footer-row {
    gap: 16px;
    flex-direction: column;
    justify-content: center;
  }
}