/* === RESET & BASE === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --blue:    #0070f3;
  --dark:    #0a0e1a;
  --dark2:   #111827;
  --mid:     #1e2d47;
  --text:    #e2e8f0;
  --muted:   #94a3b8;
  --accent:  #38bdf8;
  --border:  rgba(255,255,255,0.08);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: #ffffff;
  color: #1a1a2e;
  line-height: 1.7;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* === HEADER === */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 14, 26, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.logo {
  font-size: 1.2rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: -0.5px;
}
.logo span { color: var(--accent); }

nav { display: flex; gap: 0.5rem; }

.nav-group {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: default;
  padding: 0.4rem 0.8rem;
  border-radius: 6px;
  transition: color 0.2s, background 0.2s;
  user-select: none;
}
.dropdown:hover .nav-group { color: #fff; background: rgba(255,255,255,0.07); }

.dropdown { position: relative; }

.dropdown-menu {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  background: #0f1829;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.5rem;
  min-width: 180px;
  z-index: 200;
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}
.dropdown:hover .dropdown-menu { display: flex; flex-direction: column; }

.dropdown-menu a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  padding: 0.5rem 0.8rem;
  border-radius: 6px;
  transition: color 0.15s, background 0.15s;
}
.dropdown-menu a:hover { color: #fff; background: rgba(255,255,255,0.07); }

/* === HERO === */
.hero {
  background: var(--dark);
  background-image: radial-gradient(ellipse at 60% 40%, rgba(0,112,243,0.15) 0%, transparent 60%),
                    radial-gradient(ellipse at 20% 80%, rgba(56,189,248,0.08) 0%, transparent 50%);
  padding: 7rem 0 6rem;
  text-align: center;
  color: #fff;
}

.hero-tag {
  display: inline-block;
  background: rgba(56,189,248,0.15);
  color: var(--accent);
  border: 1px solid rgba(56,189,248,0.3);
  padding: 0.3rem 1rem;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
}

.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -1px;
  margin-bottom: 1.5rem;
}

.hero-sub {
  font-size: 1.15rem;
  color: var(--muted);
  max-width: 580px;
  margin: 0 auto 2.5rem;
}

.btn {
  display: inline-block;
  background: var(--blue);
  color: #fff;
  padding: 0.8rem 2rem;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  transition: background 0.2s, transform 0.1s;
}
.btn:hover { background: #0060d0; transform: translateY(-1px); }

/* === SECTIONS === */
.section {
  padding: 5rem 0;
  background: #ffffff;
}

.section-dark {
  background: var(--dark2);
  color: var(--text);
}
.section-dark .section-label { color: var(--accent); }
.section-dark h2 { color: #fff; }
.section-dark h3 { color: #fff; }
.section-dark p { color: var(--muted); }

.section-label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 0.6rem;
}

h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 1.2rem;
  line-height: 1.2;
}

.section-intro {
  font-size: 1.1rem;
  color: #4a5568;
  max-width: 680px;
  margin-bottom: 3rem;
}
.section-dark .section-intro { color: var(--muted); }

/* === CARDS === */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.card {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 2rem;
}

.card-icon { font-size: 2rem; margin-bottom: 1rem; }
.card-icon:empty { display: none; }
.card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 0.6rem; }
.card p { color: #4a5568; font-size: 0.95rem; }

/* === DARK CARDS (used in Research section) === */
.research-cards { margin-top: 2rem; }

.dark-card {
  background: var(--mid);
  border: 1px solid var(--border);
}
.dark-card h3 { color: #fff; }
.dark-card p { color: var(--muted); }

/* === STEPS === */
.steps { display: flex; flex-direction: column; gap: 0; margin-top: 2rem; }

.step {
  display: flex;
  gap: 2rem;
  padding: 2rem 0;
  border-bottom: 1px solid var(--border);
}
.step:last-child { border-bottom: none; }

.step-num {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent);
  opacity: 0.4;
  min-width: 60px;
  line-height: 1;
}

.step-content h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.step-content p { font-size: 0.95rem; }
.step-content em { color: var(--accent); font-style: normal; font-weight: 600; }

/* === SPLIT === */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
  margin-top: 2rem;
}

.split-text h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 1.5rem 0 0.5rem;
  color: #1a1a2e;
}
.split-text h3:first-child { margin-top: 0; }
.split-text p { color: #4a5568; font-size: 0.95rem; margin-bottom: 1rem; }

.split-visual { display: flex; flex-direction: column; gap: 1rem; }

.stat-box {
  background: var(--mid);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem 2rem;
}

.stat {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 0.4rem;
}

.stat-label { font-size: 0.85rem; color: var(--muted); }

/* === ADVANTAGES GRID === */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.advantage {
  background: var(--mid);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.8rem;
}

.advantage h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  color: #fff;
}
.advantage p { font-size: 0.9rem; color: var(--muted); }

/* === APP LIST === */
.app-list { display: flex; flex-direction: column; gap: 0; margin-top: 2rem; }

.app-item {
  display: flex;
  gap: 2rem;
  padding: 2rem 0;
  border-bottom: 1px solid #e2e8f0;
}
.app-item:last-child { border-bottom: none; }

.app-num {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--blue);
  min-width: 30px;
  padding-top: 0.3rem;
}

.app-content h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.4rem;
}
.app-content p { font-size: 0.9rem; color: #4a5568; }

/* === FOOTER === */
footer {
  background: var(--dark);
  color: var(--muted);
  padding: 3rem 0;
  text-align: center;
}

.footer-inner .logo { margin-bottom: 0.8rem; }
.footer-inner p { font-size: 0.9rem; max-width: 400px; margin: 0 auto 0.5rem; }
.copyright { font-size: 0.8rem; opacity: 0.5; margin-top: 1.5rem !important; }

/* === WELDING MODES === */
.mode-list { display: flex; flex-direction: column; gap: 1.5rem; margin-top: 2rem; }

.mode-item {
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  overflow: hidden;
}

.mode-header {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  padding: 1.2rem 1.8rem;
  background: #f8fafc;
  border-bottom: 1px solid #e2e8f0;
}

.mode-indicator {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  flex-shrink: 0;
}
.mode-indicator.conduction  { background: #38bdf8; box-shadow: 0 0 8px rgba(56,189,248,0.6); }
.mode-indicator.transition  { background: #fb923c; box-shadow: 0 0 8px rgba(251,146,60,0.6); }
.mode-indicator.keyhole     { background: #f43f5e; box-shadow: 0 0 8px rgba(244,63,94,0.6); }

.mode-tag {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #94a3b8;
  margin-bottom: 0.2rem;
}

.mode-header h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin: 0;
}

.mode-density {
  margin-left: auto;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--blue);
  background: rgba(0,112,243,0.08);
  border: 1px solid rgba(0,112,243,0.2);
  padding: 0.3rem 0.8rem;
  border-radius: 999px;
  white-space: nowrap;
}

.mode-body {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 0;
  padding: 0;
}

.mode-text {
  padding: 1.5rem 1.8rem;
  border-right: 1px solid #e2e8f0;
}
.mode-text p { font-size: 0.9rem; color: #4a5568; margin-bottom: 0.8rem; }
.mode-text p:last-child { margin-bottom: 0; }
.mode-text em { font-style: normal; font-weight: 600; color: #1a1a2e; }

.mode-specs {
  padding: 1.5rem;
  background: #fafbfc;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.spec { display: flex; flex-direction: column; gap: 0.1rem; }
.spec-label { font-size: 0.7rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.07em; color: #94a3b8; }
.spec-val { font-size: 0.85rem; color: #1a1a2e; font-weight: 500; }

/* === ON-THE-FLY === */
.otf-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

/* === LIGHT ADVANTAGE CARDS (Sensors section) === */
.light-card {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
}
.light-card h3 { color: #1a1a2e; }
.light-card p { color: #4a5568; }

/* === OCT BOX === */
.oct-box {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 2.5rem;
  color: var(--text);
}
.oct-box h3 {
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
  margin: 0.6rem 0 1.5rem;
}
.oct-body {
  display: grid;
  grid-template-columns: 1fr 240px;
  gap: 3rem;
  align-items: start;
}
.oct-text p { color: var(--muted); font-size: 0.92rem; margin-bottom: 1rem; }
.oct-text h4 { color: #fff; font-size: 0.9rem; font-weight: 700; margin: 1.2rem 0 0.6rem; }
.oct-text ul { padding-left: 1.2rem; }
.oct-text li { color: var(--muted); font-size: 0.88rem; margin-bottom: 0.5rem; }
.oct-text strong { color: var(--accent); font-weight: 600; }
.oct-stats { display: flex; flex-direction: column; gap: 0.8rem; }

/* === BRIGHTLINE BOX === */
.brightline-box {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 2.5rem;
  color: var(--text);
}

.brightline-header {
  margin-bottom: 1.5rem;
}
.brightline-badge {
  display: inline-block;
  background: rgba(56,189,248,0.15);
  color: var(--accent);
  border: 1px solid rgba(56,189,248,0.3);
  padding: 0.25rem 0.8rem;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.6rem;
}
.brightline-header h3 {
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
}

.brightline-body {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 3rem;
  align-items: start;
}

.brightline-text p { color: var(--muted); font-size: 0.95rem; margin-bottom: 1rem; }
.brightline-text h4 { color: #fff; font-size: 0.95rem; font-weight: 700; margin: 1.2rem 0 0.6rem; }
.brightline-text ul { padding-left: 1.2rem; }
.brightline-text li { color: var(--muted); font-size: 0.9rem; margin-bottom: 0.4rem; }

.brightline-visual { display: flex; flex-direction: column; align-items: center; gap: 1.5rem; }

.beam-diagram { text-align: center; }
.beam-ring {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: radial-gradient(circle, transparent 30%, rgba(56,189,248,0.5) 30%, rgba(56,189,248,0.5) 60%, transparent 60%);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 0.8rem;
  border: 2px solid rgba(56,189,248,0.3);
}
.beam-core {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: radial-gradient(circle, #fff 0%, var(--accent) 60%, transparent 100%);
  box-shadow: 0 0 20px rgba(56,189,248,0.8);
}
.diagram-label { font-size: 0.78rem; color: var(--muted); }

.brightline-stats { width: 100%; }
.bl-stat {
  background: var(--mid);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.2rem;
  margin-bottom: 0.8rem;
  text-align: center;
}
.bl-num { font-size: 1.8rem; font-weight: 800; color: var(--accent); }
.bl-label { font-size: 0.78rem; color: var(--muted); }

/* === PFO BOX === */
.pfo-box {
  background: var(--mid);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 2.5rem;
  margin-top: 1rem;
}
.pfo-box h3 {
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 1.5rem;
}
.pfo-text p { color: var(--muted); font-size: 0.95rem; margin-bottom: 1rem; }
.pfo-features { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin-top: 1.5rem; }
.pfo-feature {
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.2rem;
}
.pfo-feature strong { display: block; color: var(--accent); font-size: 0.9rem; margin-bottom: 0.3rem; }
.pfo-feature span { color: var(--muted); font-size: 0.85rem; }

/* === SUPPLIERS === */
.supplier-category {
  font-size: 1rem;
  font-weight: 700;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 2.5rem 0 1.2rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid #e2e8f0;
}

.supplier-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.2rem;
}

.supplier-card {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 1.5rem;
}
.supplier-name {
  font-size: 1.05rem;
  font-weight: 800;
  color: #1a1a2e;
  margin-bottom: 0.15rem;
}
.supplier-country {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.7rem;
}
.supplier-card p { font-size: 0.88rem; color: #4a5568; }

/* === SCROLL REVEAL === */
.reveal {
  opacity: 0;
  transform: translateY(36px) scale(0.98);
  transition: opacity 0.55s ease, transform 0.55s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0) scale(1);
}

/* === RESPONSIVE === */
@media (max-width: 768px) {
  nav { display: none; }

  .split {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .step { flex-direction: column; gap: 0.5rem; }
  .step-num { font-size: 1.5rem; }

  .app-item { flex-direction: column; gap: 0.5rem; }

  .dropdown-menu { position: static; box-shadow: none; border: none; padding: 0 0 0 1rem; }
  .dropdown { border-bottom: 1px solid var(--border); padding: 0.5rem 0; }
  nav { flex-direction: column; padding: 0.5rem 0; }

  .oct-body { grid-template-columns: 1fr; }
  .mode-body { grid-template-columns: 1fr; }
  .mode-text { border-right: none; border-bottom: 1px solid #e2e8f0; }
  .mode-density { display: none; }
  .brightline-body { grid-template-columns: 1fr; }
  .brightline-visual { flex-direction: row; flex-wrap: wrap; justify-content: center; }
  .pfo-features { grid-template-columns: 1fr; }
}