/* Core dark theme styling for Poly To Xin Trading */
:root {
  --bg-primary: #0e1117;
  --bg-secondary: #161b22;
  --bg-accent: #1f2633;
  --text-primary: #f2f4f8;
  --text-secondary: #c3c8d4;
  --brand-green: #89c44d;
  --brand-blue: #3a8dcc;
  --brand-orange: #d2903b;
  --max-width: 1120px;
  --transition-fast: 150ms ease-in-out;
  font-family: "Inter", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  padding: 0;
  margin: 0;
  min-height: 100%;
  background: var(--bg-primary);
  color: var(--text-primary);
}

body {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

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

p {
  line-height: 1.6;
  color: var(--text-secondary);
}

main {
  width: 100%;
  max-width: var(--max-width);
  padding: 3rem 1.5rem 5rem;
}

.site-header {
  width: 100%;
  background: rgba(15, 18, 24, 0.95);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid #1f2530;
}

.site-header .inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  flex-wrap: nowrap;
}

.site-header .header-actions {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex: 1 1 auto;
  min-width: 0;
  margin-left: clamp(1.5rem, 3vw, 2.3rem);
  flex-wrap: nowrap;
}

.language-switch {
  display: flex;
  align-items: center;
  margin-left: auto;
  position: relative;
  font-size: 0.9rem;
}

.language-switch select {
  appearance: none;
  background: var(--bg-secondary);
  border: 1px solid #273144;
  border-radius: 8px;
  color: var(--text-primary);
  font: inherit;
  padding: 0.35rem 2.25rem 0.35rem 0.75rem;
  cursor: pointer;
  min-width: 6.25rem;
}

.language-switch select:focus {
  outline: 2px solid var(--brand-green);
  outline-offset: 2px;
}

.language-switch::after {
  content: "";
  position: absolute;
  right: 0.9rem;
  top: 50%;
  transform: translateY(-50%);
  border: 0.35rem solid transparent;
  border-top-color: var(--text-secondary);
  pointer-events: none;
}

.brand {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: 0.04em;
  white-space: nowrap;
}

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

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 1.15rem;
  margin: 0;
  padding: 0;
}

nav {
  flex: 0 1 auto;
}

nav li a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 0.45rem 0.6rem;
  border-radius: 8px;
  transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
  font-weight: 500;
  line-height: 1.3;
  white-space: normal;
  min-width: 5.2rem;
  max-width: 6.9rem;
}

nav li a:hover,
nav li a:focus {
  background: var(--bg-accent);
  color: var(--brand-green);
}

.hero {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  background: var(--bg-secondary);
  padding: 3.5rem 3rem;
  border-radius: 18px;
  border: 1px solid #202835;
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.35);
  margin-bottom: 3rem;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  line-height: 1.15;
  margin: 0;
}

.hero .cta {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  background: linear-gradient(120deg, var(--brand-green), var(--brand-blue));
  color: #080b11;
  padding: 0.85rem 1.5rem;
  border-radius: 999px;
  font-weight: 600;
  margin-top: 1.25rem;
  transition: transform var(--transition-fast);
}

.hero .cta:hover {
  transform: translateY(-3px);
}

.stats-grid,
.pillars-grid,
.products-grid,
.value-cards {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.card {
  background: var(--bg-secondary);
  border-radius: 14px;
  padding: 1.5rem;
  border: 1px solid #202835;
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.card:hover {
  transform: translateY(-4px);
  border-color: var(--brand-green);
}

.card h3 {
  margin-top: 0;
  color: var(--text-primary);
}

.section {
  margin-bottom: 3.5rem;
}

.section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 2rem;
  margin-bottom: 1rem;
}

.section-header h2 {
  margin: 0;
  font-size: 1.75rem;
}

.section-header p {
  margin: 0;
}

.footer {
  width: 100%;
  background: var(--bg-secondary);
  border-top: 1px solid #1f2530;
  padding: 2rem 1.5rem;
  margin-top: auto;
}

.footer .inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  gap: 1.5rem;
  color: var(--text-secondary);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.footer-contact {
  font-size: 0.95rem;
  line-height: 1.6;
}

.footer-contact a {
  color: var(--brand-green);
}

.footer-copy {
  font-size: 0.85rem;
  color: #7a8398;
}

.breadcrumb {
  margin: 1.5rem 0;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.breadcrumb a {
  color: var(--brand-green);
}

.product-header {
  background: var(--bg-secondary);
  padding: 2.5rem;
  border-radius: 18px;
  border: 1px solid #202835;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
  margin-bottom: 2.5rem;
}

.product-header h1 {
  margin-top: 0;
  font-size: 2.25rem;
}

.product-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1.5rem;
}

.tag {
  background: rgba(137, 196, 77, 0.12);
  color: var(--brand-green);
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.two-column {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2rem;
  margin-bottom: 2.5rem;
}

.highlight-box {
  background: var(--bg-accent);
  border-radius: 12px;
  padding: 1.5rem;
  border: 1px solid #273144;
}

.process-steps {
  counter-reset: step-counter;
  display: grid;
  gap: 1rem;
}

.process-step {
  background: var(--bg-accent);
  border-radius: 10px;
  padding: 1.25rem;
  border: 1px solid #273144;
  position: relative;
  padding-left: 3.5rem;
}

.process-step::before {
  counter-increment: step-counter;
  content: counter(step-counter);
  position: absolute;
  left: 1rem;
  top: 1.25rem;
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 50%;
  background: linear-gradient(120deg, var(--brand-green), var(--brand-blue));
  color: #05070b;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
}

.contact-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
}

.contact-card {
  background: var(--bg-secondary);
  border-radius: 14px;
  padding: 1.75rem;
  border: 1px solid #202835;
}

.contact-card h3 {
  margin-top: 0;
}

.button-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.25rem;
  border-radius: 8px;
  background: rgba(58, 141, 204, 0.15);
  color: var(--brand-blue);
  font-weight: 600;
  transition: background var(--transition-fast), color var(--transition-fast);
}

.button-secondary:hover {
  background: rgba(58, 141, 204, 0.25);
  color: #9cd5ff;
}

.table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
}

.table th,
.table td {
  border: 1px solid #273144;
  padding: 0.75rem;
  text-align: left;
}

.table th {
  background: rgba(58, 141, 204, 0.15);
  color: var(--text-primary);
}

.table td {
  color: var(--text-secondary);
}

.table caption {
  margin-bottom: 0.75rem;
  font-weight: 600;
  color: var(--text-primary);
}

.cta-strip {
  background: linear-gradient(120deg, rgba(137, 196, 77, 0.15), rgba(58, 141, 204, 0.15));
  border: 1px solid #273144;
  border-radius: 16px;
  padding: 2.5rem;
  display: grid;
  gap: 1rem;
  margin-top: 3rem;
}

.cta-strip strong {
  font-size: 1.35rem;
}

@media (max-width: 860px) {
  .nav-toggle {
    display: block;
  }

  .site-header .inner {
    flex-wrap: nowrap;
    align-items: center;
    gap: 0.6rem;
  }

  .site-header .header-actions {
    width: auto;
    flex-wrap: nowrap;
    align-items: center;
    justify-content: flex-end;
    gap: 0.5rem;
    margin-left: auto;
  }

  .language-switch {
    order: 0;
    width: auto;
    margin-left: 0;
  }

  .language-switch select {
    font-size: 1rem;
    min-width: 7.25rem;
    width: auto;
  }

  .nav-toggle {
    order: 1;
    margin-left: 0;
  }

  nav {
    position: fixed;
    inset: 0;
    padding: calc(4.5rem + env(safe-area-inset-top)) 1.75rem 2.5rem;
    background: rgba(14, 17, 23, 0.96);
    transform: translateY(-100%);
    transition: transform 220ms ease-in-out, opacity 220ms ease-in-out;
    display: flex;
    flex-direction: column;
    z-index: 250;
    pointer-events: none;
    opacity: 0;
    will-change: transform, opacity;
    overflow-y: auto;
    gap: 1.5rem;
    height: 100vh;
    max-height: 100vh;
  }

  nav.open {
    transform: translateY(0);
    pointer-events: auto;
    opacity: 1;
  }

  nav ul {
    flex-direction: column;
    gap: 1.25rem;
    font-size: 1.15rem;
    align-items: flex-start;
    width: 100%;
  }

  nav li a {
    max-width: none;
    min-width: 0;
    justify-content: flex-start;
    text-align: left;
    width: 100%;
  }

  .hero {
    padding: 2.5rem 2rem;
  }
}