/* LAFCO — Lao Cai Fused Phosphate Fertilizer JSC
 * Landing page v1 stylesheet
 * Plain CSS, no build. Mobile-first. Targets modern browsers.
 */

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, p, figure, blockquote, ul, ol { margin: 0; padding: 0; }
ul, ol { list-style: none; }
img, picture, svg, video { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: 0; background: transparent; }

/* ---- Brand tokens ---- */
:root {
  --color-forest: #1e5c1e;
  --color-forest-dark: #0f3a0f;
  --color-leaf: #7bc043;
  --color-leaf-soft: #a8d87a;
  --color-gold: #c9a227;
  --color-ink: #1a2e1a;
  --color-muted: #4a6a4a;
  --color-paper: #ffffff;
  --color-cream: #f7faf2;
  --color-mist: #e8f2dc;
  --color-border: #dbe7c9;

  --font-display: 'Montserrat', 'Be Vietnam Pro', system-ui, -apple-system, sans-serif;
  --font-body: 'Be Vietnam Pro', system-ui, -apple-system, 'Segoe UI', sans-serif;

  --step-0: 1rem;            /* 16px */
  --step-1: 1.125rem;        /* 18px body */
  --step-2: 1.375rem;        /* 22px */
  --step-3: 1.75rem;         /* 28px */
  --step-4: 2.25rem;         /* 36px */
  --step-5: 2.875rem;        /* 46px */
  --step-6: 3.75rem;         /* 60px */

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --space-9: 6rem;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;

  --shadow-sm: 0 1px 2px rgba(15, 58, 15, 0.06), 0 2px 8px rgba(15, 58, 15, 0.05);
  --shadow-md: 0 4px 14px rgba(15, 58, 15, 0.10);

  --container: 1200px;
}

/* ---- Base typography ---- */
body {
  font-family: var(--font-body);
  font-size: var(--step-1);
  line-height: 1.6;
  color: var(--color-ink);
  background: var(--color-paper);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.15;
  color: var(--color-forest-dark);
  letter-spacing: -0.01em;
}

h1 { font-size: var(--step-5); }
h2 { font-size: var(--step-4); }
h3 { font-size: var(--step-3); }
h4 { font-size: var(--step-2); font-weight: 700; }

@media (min-width: 768px) {
  h1 { font-size: var(--step-6); }
}

p { max-width: 62ch; }
p.lead { font-size: var(--step-2); color: var(--color-muted); }

/* ---- Layout utilities ---- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--space-5);
}
@media (min-width: 768px) {
  .container { padding-inline: var(--space-7); }
}

.section { padding-block: var(--space-8); }
@media (min-width: 768px) {
  .section { padding-block: var(--space-9); }
}

.section--alt { background: var(--color-cream); }
.section--forest { background: var(--color-forest-dark); color: #f2f7ef; }
.section--forest h2, .section--forest h3 { color: var(--color-paper); }
.section--forest p.lead { color: #c7d9bf; }

.stack > * + * { margin-top: var(--space-4); }
.stack-lg > * + * { margin-top: var(--space-6); }

.row { display: flex; flex-wrap: wrap; gap: var(--space-4); align-items: center; }

.grid { display: grid; gap: var(--space-5); grid-template-columns: 1fr; }
@media (min-width: 640px) { .grid-2 { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 900px) {
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-5 { grid-template-columns: repeat(5, 1fr); }
}

/* ---- Components ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  font-size: var(--step-0);
  border-radius: var(--radius-sm);
  transition: background 0.18s ease, transform 0.18s ease, box-shadow 0.18s ease;
  white-space: nowrap;
}
.btn-primary {
  background: var(--color-forest);
  color: var(--color-paper);
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { background: var(--color-forest-dark); box-shadow: var(--shadow-md); }
.btn-ghost {
  background: transparent;
  color: var(--color-forest-dark);
  border: 1.5px solid var(--color-forest);
}
.btn-ghost:hover { background: var(--color-mist); }
.btn-ghost--light {
  color: #f2f7ef;
  border-color: var(--color-leaf-soft);
}
.btn-ghost--light:hover { background: rgba(255,255,255,0.1); }

.badge {
  display: inline-block;
  padding: 0.25rem 0.6rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-forest-dark);
  background: var(--color-mist);
  border-radius: 999px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.card {
  background: var(--color-paper);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.card--feature {
  background: linear-gradient(180deg, var(--color-mist), var(--color-paper));
}
.card h3 { font-size: var(--step-2); }
.card__meta { font-size: 0.9rem; color: var(--color-muted); }
.card__img {
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: var(--radius-sm);
  width: 100%;
  background: var(--color-mist);
}

/* ---- Site header ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255,255,255,0.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--color-border);
}
.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-block: var(--space-3);
}
.brand { display: flex; align-items: center; gap: var(--space-3); }
.brand img { width: 44px; height: 44px; }
.brand__name { font-family: var(--font-display); font-weight: 800; font-size: var(--step-2); color: var(--color-forest-dark); letter-spacing: 0.04em; }
.brand__sub { font-size: 0.8rem; color: var(--color-muted); display: none; }
@media (min-width: 768px) { .brand__sub { display: block; } }

.nav { display: none; gap: var(--space-6); }
@media (min-width: 900px) { .nav { display: flex; } }
.nav a { font-weight: 500; color: var(--color-ink); }
.nav a:hover { color: var(--color-forest); }

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 0.9rem;
  font-weight: 600;
}
.lang-switch a { padding: 0.3rem 0.55rem; border-radius: var(--radius-sm); color: var(--color-muted); }
.lang-switch a[aria-current="page"] { background: var(--color-forest); color: var(--color-paper); }

/* ---- Hero ---- */
.hero {
  padding-block: var(--space-8) var(--space-7);
  background:
    radial-gradient(circle at 10% 0%, var(--color-mist) 0%, transparent 40%),
    linear-gradient(180deg, var(--color-paper) 0%, var(--color-cream) 100%);
}
.hero__inner {
  display: grid;
  gap: var(--space-7);
  align-items: center;
}
@media (min-width: 900px) {
  .hero__inner { grid-template-columns: 1.1fr 0.9fr; }
}
.hero__eyebrow { color: var(--color-forest); font-weight: 700; font-size: 0.9rem; text-transform: uppercase; letter-spacing: 0.08em; }
.hero__title { margin-top: var(--space-3); }
.hero__title em { font-style: normal; color: var(--color-leaf); }
.hero__lead { margin-top: var(--space-5); color: var(--color-muted); }
.hero__ctas { margin-top: var(--space-6); display: flex; gap: var(--space-3); flex-wrap: wrap; }
.hero__media {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  aspect-ratio: 3 / 4;
  max-height: 560px;
}
.hero__media img { width: 100%; height: 100%; object-fit: cover; }

/* ---- Stats band ---- */
.stats {
  background: var(--color-forest-dark);
  color: #e9f2dc;
}
.stats .grid { padding-block: var(--space-6); }
.stat__num {
  font-family: var(--font-display);
  font-size: var(--step-5);
  font-weight: 800;
  color: var(--color-leaf-soft);
  line-height: 1;
}
.stat__label { font-size: 0.95rem; color: #c7d9bf; margin-top: var(--space-2); }

/* ---- Products section ---- */
.product-card {
  overflow: hidden;
  padding: 0;
}
.product-card__body { padding: var(--space-5); flex: 1; display: flex; flex-direction: column; gap: var(--space-3); }
.product-card__specs {
  font-size: 0.9rem;
  color: var(--color-muted);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}
.product-card__specs li::before { content: "• "; color: var(--color-leaf); }

/* ---- About / contact ---- */
.about__media {
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 4 / 3;
}
.about__media img { width: 100%; height: 100%; object-fit: cover; }
.contact-card { background: var(--color-paper); padding: var(--space-6); border-radius: var(--radius-md); border: 1px solid var(--color-border); }
.contact-card dt { font-weight: 700; color: var(--color-muted); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.05em; margin-top: var(--space-3); }
.contact-card dt:first-child { margin-top: 0; }
.contact-card dd { margin: 0; font-size: var(--step-1); }
.contact-card a { color: var(--color-forest); }
.contact-card a:hover { text-decoration: underline; }

/* ---- Footer ---- */
.site-footer {
  background: var(--color-forest-dark);
  color: #c7d9bf;
  padding-block: var(--space-7);
  font-size: 0.95rem;
}
.site-footer a { color: #e9f2dc; }
.site-footer a:hover { color: var(--color-paper); }
.site-footer .brand__name { color: var(--color-paper); }
.site-footer__cols { display: grid; gap: var(--space-6); grid-template-columns: 1fr; }
@media (min-width: 768px) { .site-footer__cols { grid-template-columns: 1.4fr 1fr 1fr; } }
.site-footer__bottom {
  margin-top: var(--space-7);
  padding-top: var(--space-5);
  border-top: 1px solid rgba(231, 242, 220, 0.15);
  font-size: 0.85rem;
  color: #a8c19e;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: var(--space-3);
}

/* ---- Accessibility ---- */
:focus-visible { outline: 3px solid var(--color-leaf); outline-offset: 2px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); border: 0; }

/* ---- Motion ---- */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}