/* ─────────────────────────────────────────────────────────────
   Rial Electronics — single-page site styles
   Aesthetic: dark technical, precision instrument, minimal
   ───────────────────────────────────────────────────────────── */

:root {
  --bg:           #0b0d0f;
  --bg-alt:       #111418;
  --surface:      #15191e;
  --border:       #1f252c;
  --border-strong:#2a323b;
  --text:         #e7ebef;
  --text-dim:     #9aa4ae;
  --text-faint:   #6b757f;
  --accent:       #d8dde2;
  --accent-line:  #ffffff;

  --font-sans:    'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono:    'JetBrains Mono', 'SF Mono', Menlo, Consolas, monospace;

  --max:          1200px;
  --gutter:       2rem;
  --radius:       0;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--text);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 120ms ease, color 120ms ease;
}
a:hover { border-bottom-color: var(--accent-line); }

h1, h2, h3 {
  margin: 0;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
}

p { margin: 0; color: var(--text-dim); }

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* ── Header ────────────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 13, 15, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  border: none;
}
.brand-mark {
  color: var(--accent-line);
  font-size: 0.95rem;
}
.brand-name {
  color: var(--text);
  font-weight: 500;
}
.nav {
  display: flex;
  gap: 2rem;
}
.nav a {
  font-size: 0.85rem;
  color: var(--text-dim);
  font-weight: 400;
  letter-spacing: 0.02em;
}
.nav a:hover { color: var(--text); border-bottom-color: var(--accent-line); }

/* ── Hero ──────────────────────────────────────────────────── */
.hero {
  padding: 7rem 0 6rem;
  border-bottom: 1px solid var(--border);
  background:
    linear-gradient(to bottom, var(--bg) 0%, var(--bg) 70%, var(--bg-alt) 100%);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 80px 80px;
  background-position: -1px -1px;
  opacity: 0.25;
  pointer-events: none;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
}
.hero > .container { position: relative; z-index: 1; }

.hero-meta {
  display: flex;
  gap: 0.8rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-faint);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 2rem;
}
.kicker-divider { color: var(--border-strong); }

.hero-title {
  font-size: clamp(2.5rem, 5.5vw, 4.5rem);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -0.025em;
  margin-bottom: 1.8rem;
  max-width: 18ch;
}
.hero-sub {
  font-size: 1.1rem;
  line-height: 1.6;
  max-width: 58ch;
  color: var(--text-dim);
  margin-bottom: 2.5rem;
}
.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  padding: 0.85rem 1.6rem;
  font-size: 0.88rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  border: 1px solid var(--border-strong);
  transition: background-color 120ms ease, border-color 120ms ease, color 120ms ease;
}
.btn-primary {
  background: var(--text);
  color: var(--bg);
  border-color: var(--text);
}
.btn-primary:hover {
  background: var(--accent);
  border-color: var(--accent);
}
.btn-ghost {
  background: transparent;
  color: var(--text);
}
.btn-ghost:hover {
  border-color: var(--accent-line);
  background: var(--surface);
}
.btn:hover { border-bottom-color: transparent; }

/* ── Sections ──────────────────────────────────────────────── */
.section {
  padding: 6rem 0;
  border-bottom: 1px solid var(--border);
}
.section-alt {
  background: var(--bg-alt);
}
.section-head {
  display: flex;
  align-items: baseline;
  gap: 1.5rem;
  margin-bottom: 3.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}
.section-num {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-faint);
  letter-spacing: 0.15em;
}
.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}

/* ── Grid utilities ────────────────────────────────────────── */
.grid {
  display: grid;
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
}
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card,
.focus {
  background: var(--bg);
  padding: 2rem;
}
.section-alt .card,
.section-alt .focus {
  background: var(--bg-alt);
}
.card h3,
.focus h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.7rem;
  letter-spacing: -0.005em;
}
.card p,
.focus p {
  font-size: 0.93rem;
  line-height: 1.6;
}

/* ── Products ──────────────────────────────────────────────── */
.product {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border);
}
.product:first-of-type { border-top: none; padding-top: 0; }
.product:last-of-type { padding-bottom: 0; }

.product-tag {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.2rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.tag {
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--border-strong);
  color: var(--text-dim);
}
.status {
  color: var(--text-faint);
}
.product-title {
  font-family: var(--font-mono);
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 500;
  letter-spacing: -0.01em;
  margin-bottom: 1rem;
  color: var(--text);
}
.product-desc {
  font-size: 1.02rem;
  max-width: 70ch;
  margin-bottom: 2rem;
  color: var(--text-dim);
}
.specs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  margin: 0;
  border-top: 1px solid var(--border);
  border-left: 1px solid var(--border);
}
.specs > div {
  padding: 1rem 1.2rem;
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}
.specs dt {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-faint);
  margin: 0 0 0.4rem;
}
.specs dd {
  margin: 0;
  font-size: 0.95rem;
  color: var(--text);
  font-weight: 500;
}

/* ── Contact ───────────────────────────────────────────────── */
.contact-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 4rem;
  align-items: start;
}
.contact-lead {
  font-size: 1.05rem;
  margin-bottom: 2rem;
  max-width: 50ch;
}
.contact-list {
  list-style: none;
  padding: 0;
  margin: 0;
  border-top: 1px solid var(--border);
}
.contact-list li {
  display: flex;
  align-items: baseline;
  gap: 2rem;
  padding: 1.1rem 0;
  border-bottom: 1px solid var(--border);
}
.contact-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
  min-width: 9rem;
}
.contact-list a {
  font-size: 1rem;
  color: var(--text);
}

.contact-meta {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  padding: 1.5rem;
  border: 1px solid var(--border);
  background: var(--surface);
}
.meta-block {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}
.meta-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
}
.meta-value {
  font-size: 0.95rem;
  color: var(--text);
}

/* ── Footer ────────────────────────────────────────────────── */
.site-footer {
  padding: 2.5rem 0;
  background: var(--bg);
  border-top: 1px solid var(--border);
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-faint);
  letter-spacing: 0.05em;
}
.footer-left {
  display: flex;
  align-items: center;
  gap: 0.7rem;
}
.footer-right {
  display: flex;
  gap: 0.8rem;
  align-items: center;
}
.footer-divider { color: var(--border-strong); }

/* ── Responsive ────────────────────────────────────────────── */
@media (max-width: 900px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .specs  { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; gap: 2.5rem; }
  .nav { gap: 1.2rem; }
}

@media (max-width: 640px) {
  :root { --gutter: 1.25rem; }
  .hero { padding: 4.5rem 0 4rem; }
  .section { padding: 4rem 0; }
  .grid-3, .grid-2 { grid-template-columns: 1fr; }
  .specs  { grid-template-columns: 1fr; }
  .header-inner { height: 56px; }
  .nav { display: none; }
  .hero-title { font-size: 2.2rem; }
  .contact-list li { flex-direction: column; gap: 0.3rem; }
  .contact-label { min-width: 0; }
  .footer-inner { flex-direction: column; align-items: flex-start; gap: 0.8rem; }
}

/* ── Selection ─────────────────────────────────────────────── */
::selection {
  background: var(--text);
  color: var(--bg);
}