/* ===== Variables ===== */
:root {
  --color-bg: #080c12;
  --color-bg-elevated: #0d1219;
  --color-bg-card: #121a24;
  --color-surface: #151f2b;
  --color-primary: #2b8fc7;
  --color-primary-light: #5eb3e8;
  --color-primary-dark: #1a6a96;
  --color-accent: #b8e4f5;
  --color-text: #e8f2f8;
  --color-text-muted: #8aa3b5;
  --color-text-dim: #5a7285;
  --color-border: rgba(255, 255, 255, 0.08);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --header-height: 72px;
  --container-max: 1200px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

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

ul {
  list-style: none;
}

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

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-height);
  transition: background var(--transition), backdrop-filter var(--transition);
}

.header.scrolled {
  background: rgba(8, 12, 18, 0.92);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.logo-icon {
  width: 28px;
  height: 28px;
  color: var(--color-primary-light);
  flex-shrink: 0;
}

.logo-footer .logo-icon {
  color: var(--color-primary-light);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition);
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.lang-switch {
  display: flex;
  align-items: center;
  padding: 3px;
  border-radius: 100px;
  border: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.03);
}

.lang-btn {
  padding: 6px 12px;
  font-size: 0.75rem;
  font-weight: 500;
  font-family: var(--font-sans);
  color: var(--color-text-dim);
  background: none;
  border: none;
  border-radius: 100px;
  cursor: pointer;
  transition: all var(--transition);
}

.lang-btn:hover {
  color: var(--color-text-muted);
}

.lang-btn.active {
  background: var(--color-primary);
  color: #fff;
}

.nav-cta {
  font-size: 0.875rem;
  font-weight: 500;
  padding: 10px 20px;
  border: 1px solid var(--color-border);
  border-radius: 100px;
  transition: all var(--transition);
}

.nav-cta:hover {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: var(--transition);
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: 100px;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
}

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

.btn-primary:hover {
  background: var(--color-primary-light);
  transform: translateY(-1px);
}

.btn-outline {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-outline:hover {
  border-color: var(--color-primary);
  color: var(--color-primary-light);
}

.btn-outline-light {
  background: transparent;
  color: var(--color-text);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-outline-light:hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--color-primary-light);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1rem;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: var(--header-height);
}

.hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.hero-gradient {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(43, 143, 199, 0.18) 0%, transparent 60%),
    radial-gradient(ellipse 60% 40% at 80% 80%, rgba(26, 106, 150, 0.12) 0%, transparent 50%),
    linear-gradient(180deg, var(--color-bg) 0%, #0a1018 50%, var(--color-bg) 100%);
}

.hero-waves {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 200px;
  overflow: hidden;
  opacity: 0.4;
}

.wave {
  position: absolute;
  bottom: 0;
  left: -50%;
  width: 200%;
  height: 100px;
  background: linear-gradient(90deg, transparent, rgba(43, 143, 199, 0.08), transparent);
  border-radius: 40%;
  animation: waveDrift 8s ease-in-out infinite;
}

.wave-2 {
  bottom: -20px;
  opacity: 0.6;
  animation-delay: -4s;
  animation-duration: 10s;
}

@keyframes waveDrift {
  0%, 100% { transform: translateX(0) rotate(0deg); }
  50% { transform: translateX(5%) rotate(1deg); }
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 70% 70% at 50% 50%, black 20%, transparent 70%);
}

.hero-content {
  position: relative;
  text-align: center;
  padding: 80px 24px;
}

.hero-eyebrow {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-primary-light);
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 40px;
}

.hero-title-accent {
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--color-text-dim);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
}

.scroll-indicator {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, var(--color-primary), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
  50% { opacity: 1; transform: scaleY(1); }
}

/* ===== Sections ===== */
.section {
  padding: 120px 0;
}

.section-label {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-primary-light);
  margin-bottom: 20px;
}

.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.75rem);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
  max-width: 900px;
}

.section-title-sm {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  max-width: 720px;
  margin-top: 24px;
  line-height: 1.7;
}

/* About Us */
.section-what {
  background: var(--color-bg-elevated);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

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

.about-body p {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-body p:last-child {
  margin-bottom: 0;
}

.about-values {
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

.about-values p {
  font-size: 1rem;
  color: var(--color-text);
  line-height: 1.8;
  margin-bottom: 8px;
}

.about-values p:last-child {
  margin-bottom: 0;
}

.about-visual {
  aspect-ratio: 4/3;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  background: var(--color-bg-card);
}

.about-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* Periodic Table */
.section-periodic {
  padding-bottom: 100px;
  overflow: hidden;
  background:
    radial-gradient(ellipse 80% 50% at 50% 0%, rgba(43, 143, 199, 0.08) 0%, transparent 60%),
    var(--color-bg);
}

.periodic-header {
  margin-bottom: 48px;
}

.periodic-wrapper {
  position: relative;
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 16px;
}

.periodic-table {
  display: grid;
  grid-template-columns: repeat(18, 1fr);
  grid-template-rows: repeat(9, 1fr);
  gap: 3px;
  aspect-ratio: 18 / 9.8;
  max-height: 520px;
}

.element-cell {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-width: 0;
  min-height: 0;
  padding: 2px;
  border: 1px solid rgba(255, 255, 255, 0.04);
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.02);
  color: var(--color-text-dim);
  cursor: default;
  transition: border-color 0.25s, background 0.25s, transform 0.25s, box-shadow 0.25s;
  animation: elementFadeIn 0.6s ease backwards;
  animation-delay: var(--delay, 0ms);
}

@keyframes elementFadeIn {
  from { opacity: 0; transform: scale(0.85); }
  to { opacity: 1; transform: scale(1); }
}

.element-z {
  font-size: clamp(0.35rem, 0.9vw, 0.55rem);
  line-height: 1;
  opacity: 0.5;
  align-self: flex-start;
  margin-left: 2px;
}

.element-sym {
  font-size: clamp(0.55rem, 1.4vw, 0.85rem);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.element-key {
  background: linear-gradient(145deg, rgba(43, 143, 199, 0.35), rgba(94, 179, 232, 0.2));
  border-color: rgba(94, 179, 232, 0.45);
  color: var(--color-accent);
  box-shadow: 0 0 16px rgba(43, 143, 199, 0.2);
  animation: elementFadeIn 0.6s ease backwards, keyGlow 3s ease-in-out infinite;
  animation-delay: var(--delay, 0ms), calc(var(--delay, 0ms) + 0.6s);
}

@keyframes keyGlow {
  0%, 100% { box-shadow: 0 0 12px rgba(43, 143, 199, 0.15); }
  50% { box-shadow: 0 0 22px rgba(94, 179, 232, 0.35); }
}

.element-cell:hover,
.element-cell:focus-visible {
  z-index: 2;
  transform: scale(1.15);
  outline: none;
}

.element-key:hover,
.element-key:focus-visible {
  background: linear-gradient(145deg, rgba(43, 143, 199, 0.55), rgba(94, 179, 232, 0.35));
  border-color: var(--color-primary-light);
}

.element-cell:not(.element-key):hover,
.element-cell:not(.element-key):focus-visible {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.12);
  color: var(--color-text-muted);
}

.periodic-tooltip {
  position: absolute;
  z-index: 10;
  pointer-events: none;
  padding: 10px 14px;
  border-radius: 8px;
  background: rgba(12, 18, 26, 0.95);
  border: 1px solid rgba(94, 179, 232, 0.3);
  backdrop-filter: blur(12px);
  text-align: center;
  white-space: nowrap;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.tooltip-symbol {
  display: block;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary-light);
}

.tooltip-name {
  display: block;
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-top: 2px;
}

.tooltip-desc {
  display: block;
  font-size: 0.75rem;
  color: var(--color-accent);
  margin-top: 6px;
  white-space: normal;
  max-width: 180px;
}

.periodic-legend {
  display: flex;
  gap: 32px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 32px;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--color-text-dim);
}

.legend-dot {
  width: 12px;
  height: 12px;
  border-radius: 3px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.legend-dot.legend-key {
  background: linear-gradient(145deg, rgba(43, 143, 199, 0.5), rgba(94, 179, 232, 0.3));
  border-color: rgba(94, 179, 232, 0.45);
  box-shadow: 0 0 8px rgba(43, 143, 199, 0.3);
}

/* Feature Sections */
.feature-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.feature-title {
  font-size: clamp(1.5rem, 2.5vw, 2.25rem);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}

.feature-desc {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: 32px;
}

.feature-subtitle {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 16px;
}

.feature-list {
  margin-bottom: 32px;
  padding-left: 1.25em;
  color: var(--color-text-muted);
}

.feature-list li {
  font-size: 1.05rem;
  line-height: 1.7;
  margin-bottom: 12px;
}

.feature-list li:last-child {
  margin-bottom: 0;
}

.feature-image {
  aspect-ratio: 4/3;
  border-radius: 16px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}

.feature-photo {
  padding: 0;
  background: var(--color-bg-card);
}

.feature-photo-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.reg-mark {
  font-size: 0.55em;
  vertical-align: super;
  line-height: 0;
  font-weight: 500;
}

/* Ion membrane visual */
.membrane-visual {
  background: linear-gradient(145deg, #0a1420 0%, #142535 100%);
}

.membrane-stack {
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 1;
}

.membrane-layer {
  width: 140px;
  height: 28px;
  border-radius: 4px;
  border: 1px solid rgba(94, 179, 232, 0.3);
  background: linear-gradient(90deg, rgba(43, 143, 199, 0.15), rgba(94, 179, 232, 0.25), rgba(43, 143, 199, 0.15));
}

.membrane-layer:nth-child(2) {
  width: 160px;
  background: linear-gradient(90deg, rgba(43, 143, 199, 0.25), rgba(94, 179, 232, 0.35), rgba(43, 143, 199, 0.25));
}

.ion-flow {
  position: absolute;
  display: flex;
  gap: 40px;
  z-index: 2;
}

.ion {
  font-size: 1.2rem;
  font-weight: 700;
  animation: ionMove 2.5s ease-in-out infinite;
}

.ion-pos { color: #5eb3e8; }
.ion-neg { color: #f0a050; animation-delay: 0.8s; }
.ion-flow .ion:nth-child(3) { animation-delay: 1.6s; }

@keyframes ionMove {
  0%, 100% { transform: translateY(0); opacity: 0.6; }
  50% { transform: translateY(-12px); opacity: 1; }
}

.membrane-pulse {
  position: absolute;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  border: 1px solid rgba(43, 143, 199, 0.25);
  animation: membraneRing 3s ease-out infinite;
}

.membrane-pulse::before {
  content: '';
  position: absolute;
  inset: 20px;
  border-radius: 50%;
  border: 1px solid rgba(43, 143, 199, 0.15);
  animation: membraneRing 3s ease-out infinite 0.5s;
}

@keyframes membraneRing {
  0% { transform: scale(0.8); opacity: 1; }
  100% { transform: scale(1.5); opacity: 0; }
}

/* Nano composite visual */
.nano-visual {
  background: linear-gradient(145deg, #0c1218 0%, #1a2535 100%);
}

.nano-network {
  position: relative;
  width: 200px;
  height: 200px;
}

.nano-node {
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--color-primary-light);
  box-shadow: 0 0 12px rgba(94, 179, 232, 0.5);
  animation: nodePulse 3s ease-in-out infinite;
}

.node-1 { top: 20px; left: 50%; transform: translateX(-50%); }
.node-2 { top: 70px; left: 30px; animation-delay: 0.5s; }
.node-3 { top: 70px; right: 30px; animation-delay: 1s; }
.node-4 { bottom: 40px; left: 50px; animation-delay: 1.5s; }
.node-5 { bottom: 40px; right: 50px; animation-delay: 2s; }

.nano-bond {
  position: absolute;
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(94, 179, 232, 0.4), transparent);
  transform-origin: left center;
}

.bond-1 { top: 55px; left: 70px; width: 60px; transform: rotate(-20deg); }
.bond-2 { top: 55px; right: 70px; width: 60px; transform: rotate(20deg); }
.bond-3 { top: 100px; left: 60px; width: 80px; transform: rotate(30deg); }
.bond-4 { top: 100px; right: 60px; width: 80px; transform: rotate(-30deg); }

@keyframes nodePulse {
  0%, 100% { transform: scale(1); opacity: 0.7; }
  50% { transform: scale(1.3); opacity: 1; }
}

.node-1 { animation-name: nodePulseCenter; }
@keyframes nodePulseCenter {
  0%, 100% { transform: translateX(-50%) scale(1); opacity: 0.7; }
  50% { transform: translateX(-50%) scale(1.3); opacity: 1; }
}

/* Solutions grid */
.section-solutions {
  background: var(--color-bg-elevated);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.solutions-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 48px;
}

.solution-card {
  padding: 32px;
  border-radius: 12px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  transition: border-color var(--transition), transform var(--transition);
}

.solution-card:hover {
  border-color: rgba(43, 143, 199, 0.3);
  transform: translateY(-2px);
}

.solution-icon {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-primary-light);
  margin-bottom: 16px;
}

.solution-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.solution-card p {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

.section-feature-reverse .feature-grid {
  direction: rtl;
}

.section-feature-reverse .feature-grid > * {
  direction: ltr;
}

/* Stats */
.section-stats {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  padding: 80px 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  text-align: center;
}

.stat-number {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-primary-light);
}

.stat-unit {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--color-text-muted);
  margin-left: 4px;
}

.stat-label {
  font-size: 0.9rem;
  color: var(--color-text-dim);
  margin-top: 8px;
}

/* Partners */
.section-partners {
  padding-bottom: 80px;
}

.link-arrow {
  display: inline-block;
  margin-top: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-primary-light);
  transition: transform var(--transition);
}

.link-arrow:hover {
  transform: translateX(4px);
}

.partners-marquee {
  margin-top: 60px;
  overflow: hidden;
  mask-image: linear-gradient(90deg, transparent, black 10%, black 90%, transparent);
}

.partners-track {
  display: flex;
  gap: 48px;
  animation: marquee 30s linear infinite;
  width: max-content;
}

.partner-logo {
  flex-shrink: 0;
  padding: 20px 40px;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-text-dim);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  background: var(--color-bg-card);
  white-space: nowrap;
  transition: all var(--transition);
}

.partner-logo:hover {
  color: var(--color-text-muted);
  border-color: rgba(43, 143, 199, 0.3);
}

@keyframes marquee {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

/* CTA */
.section-cta {
  position: relative;
  text-align: center;
  padding: 140px 0;
  overflow: hidden;
}

.cta-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 80% at 50% 100%, rgba(43, 143, 199, 0.2) 0%, transparent 60%),
    var(--color-bg-elevated);
}

.section-cta .container {
  position: relative;
}

.cta-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.cta-desc {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  margin-bottom: 36px;
}

/* Footer */
.footer {
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
  padding: 80px 0 40px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 2fr;
  gap: 60px;
  margin-bottom: 60px;
}

.footer-tagline {
  margin-top: 16px;
  font-size: 0.9rem;
  color: var(--color-text-dim);
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.footer-col h4 {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: 16px;
}

.footer-col a {
  font-size: 0.9rem;
  color: var(--color-text-dim);
  transition: color var(--transition);
}

.footer-col a:hover {
  color: var(--color-primary-light);
}

.footer-col li + li {
  margin-top: 10px;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 40px;
  border-top: 1px solid var(--color-border);
}

.footer-address {
  font-size: 0.8rem;
  color: var(--color-text-dim);
}

.footer-social {
  display: flex;
  gap: 24px;
}

.footer-social a {
  font-size: 0.8rem;
  color: var(--color-text-dim);
  transition: color var(--transition);
}

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

.footer-copy {
  font-size: 0.8rem;
  color: var(--color-text-dim);
}

/* ===== Animations on scroll ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .about-visual {
    order: -1;
  }

  .feature-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .section-feature-reverse .feature-grid {
    direction: ltr;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .nav-actions .nav-cta {
    display: none;
  }

  .menu-toggle {
    display: flex;
  }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: rgba(8, 12, 18, 0.98);
    backdrop-filter: blur(20px);
    padding: 32px 24px;
    gap: 24px;
    border-bottom: 1px solid var(--color-border);
  }

  .section {
    padding: 80px 0;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .footer-links {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .hero-scroll {
    display: none;
  }

  .periodic-table {
    gap: 2px;
    max-height: none;
  }

  .periodic-wrapper {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 8px;
  }

  .periodic-table {
    min-width: 540px;
  }
}