/* =========================================================
   BILLIUM MINING AFRICA — Design system
   ========================================================= */

:root {
  --gold:        #F4B400;
  --gold-soft:   #FFD15C;
  --orange:      #F39C12;
  --black:       #0E0E0E;
  --black-2:     #1A1A1A;
  --brown:       #3D2F1F;
  --white:       #FFFFFF;
  --cream:       #F7F3EB;
  --grey-50:     #F5F5F5;
  --grey-100:    #ECECEC;
  --grey-300:    #BFBFBF;
  --grey-500:    #6B6B6B;
  --grey-700:    #2F2F2F;
  --shadow-md:   0 8px 24px rgba(0,0,0,.08);
  --shadow-lg:   0 24px 60px rgba(0,0,0,.18);
  --container:   1240px;
  --radius-sm:   6px;
  --radius-md:   12px;
  --radius-lg:   24px;
  --transition:  280ms cubic-bezier(.2,.7,.2,1);
}

/* ---------- Reset ---------- */
*,*::before,*::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--black);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--gold); }
button { font: inherit; cursor: pointer; border: 0; background: none; }
ul { list-style: none; padding: 0; margin: 0; }

h1,h2,h3,h4 {
  font-family: "Inter", sans-serif;
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 .6em;
  letter-spacing: -.01em;
}
h1 { font-size: clamp(2.4rem, 5vw, 4.4rem); font-weight: 800; letter-spacing: -.02em; }
h2 { font-size: clamp(1.8rem, 3.4vw, 2.8rem); }
h3 { font-size: 1.35rem; }
p  { margin: 0 0 1em; color: var(--grey-700); }

.container { width: min(100% - 2.5rem, var(--container)); margin-inline: auto; }
.text-center { text-align: center; }
.eyebrow {
  display: inline-block;
  font-size: .8rem;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 1rem;
}
.eyebrow::before { content: "—  "; color: var(--gold); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  padding: .95rem 1.7rem;
  font-weight: 600;
  font-size: .95rem;
  letter-spacing: .03em;
  border-radius: 999px;
  transition: all var(--transition);
  white-space: nowrap;
}
.btn-primary { background: var(--gold); color: var(--black); }
.btn-primary:hover { background: var(--black); color: var(--white); }
.btn-outline { border: 1.5px solid currentColor; color: var(--white); }
.btn-outline:hover { background: var(--white); color: var(--black); border-color: var(--white); }
.btn-dark { background: var(--black); color: var(--white); }
.btn-dark:hover { background: var(--gold); color: var(--black); }
.btn-arrow::after {
  content: "→";
  display: inline-block;
  transition: transform var(--transition);
}
.btn-arrow:hover::after { transform: translateX(4px); }

/* ---------- Header ---------- */
.site-header {
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 100;
  padding: .6rem 0;
  background: rgba(255,255,255,.96);
  backdrop-filter: saturate(140%) blur(10px);
  box-shadow: 0 1px 0 rgba(0,0,0,.06);
  transition: padding var(--transition), box-shadow var(--transition);
}
.site-header.scrolled {
  padding: .35rem 0;
  box-shadow: 0 6px 22px rgba(0,0,0,.08);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between; gap: 2rem;
}
.brand img { height: 78px; transition: height var(--transition); display:block; }
.site-header.scrolled .brand img { height: 60px; }
.main-nav ul {
  display: flex; gap: 2rem; align-items: center;
}
.main-nav a {
  position: relative;
  color: var(--black);
  font-weight: 500;
  font-size: .95rem;
  padding: .35rem 0;
}
.main-nav a::after {
  content:""; position:absolute; left:0; bottom:-4px;
  width:0; height:2px; background: var(--gold);
  transition: width var(--transition);
}
.main-nav a:hover::after, .main-nav a.active::after { width: 100%; }
.main-nav a.active { color: var(--gold); }
.lang-switch {
  display:flex; gap:.4rem;
  font-size:.8rem; font-weight:600; letter-spacing:.1em;
  color: var(--grey-500);
}
.lang-switch span { cursor: pointer; transition: color var(--transition); }
.lang-switch span.active { color: var(--gold); }
.lang-switch span:hover { color: var(--black); }
.header-cta { display:flex; align-items:center; gap:1.4rem; }
.menu-toggle { display:none; flex-direction: column; gap: 5px; padding: .4rem; }
.menu-toggle span { width: 26px; height: 2px; background: var(--black); transition: all var(--transition); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex; align-items: center;
  color: var(--white);
  overflow: hidden;
  padding: 11rem 0 5rem;
}
.hero-bg {
  position:absolute; inset: 0;
  background-size: cover; background-position: center;
  filter: brightness(.55);
  z-index: 0;
}
.hero::after {
  content:"";
  position:absolute; inset:0;
  background: linear-gradient(180deg, rgba(0,0,0,.35) 0%, rgba(0,0,0,.15) 35%, rgba(0,0,0,.85) 100%);
  z-index: 1;
}
.hero .container { position: relative; z-index: 2; }
.hero-content { max-width: 920px; }
.hero h1 { color: var(--white); margin-bottom: 1.2rem; }
.hero h1 .accent { color: var(--gold); }
.hero p {
  font-size: clamp(1.05rem, 1.4vw, 1.25rem);
  color: rgba(255,255,255,.85);
  max-width: 720px;
  margin-bottom: 2.4rem;
}
.hero-actions { display:flex; gap:1rem; flex-wrap: wrap; }
.hero-scroll {
  position: absolute; bottom: 2rem; left: 50%; transform: translateX(-50%);
  z-index: 2;
  color: var(--white); opacity:.7;
  font-size: .8rem; letter-spacing: .2em; text-transform: uppercase;
  text-align: center;
}
.hero-scroll::after {
  content:""; display:block; margin: .6rem auto 0;
  width: 1px; height: 40px;
  background: var(--white);
  animation: scrollLine 2s ease-in-out infinite;
}
@keyframes scrollLine {
  0%   { transform: scaleY(0); transform-origin: top; }
  50%  { transform: scaleY(1); transform-origin: top; }
  51%  { transform: scaleY(1); transform-origin: bottom; }
  100% { transform: scaleY(0); transform-origin: bottom; }
}

/* ---------- Sections ---------- */
section { padding: 6rem 0; }
section.dark { background: var(--black); color: var(--white); }
section.dark p { color: rgba(255,255,255,.75); }
section.cream { background: var(--cream); }
.section-head { max-width: 760px; margin: 0 auto 3.5rem; text-align:center; }
.section-head.left { text-align: left; margin-inline: 0; }

/* ---------- Services grid ---------- */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}
.service-card {
  position: relative;
  background: var(--white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition), box-shadow var(--transition);
  display: flex; flex-direction: column;
}
.service-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.service-card .img-wrap {
  height: 220px;
  background-size: cover; background-position: center;
  position: relative;
}
.service-card .img-wrap::after {
  content:""; position:absolute; inset:0;
  background: linear-gradient(180deg, transparent 60%, rgba(0,0,0,.5));
}
.service-card .body { padding: 1.8rem 1.6rem 2rem; flex: 1; display:flex; flex-direction:column; }
.service-card h3 { color: var(--black); margin-bottom: .6rem; }
.service-card p { color: var(--grey-700); font-size: .95rem; flex: 1; }
.service-card .more {
  margin-top: 1.2rem;
  font-size: .9rem; font-weight: 600; color: var(--black);
  display: inline-flex; align-items: center; gap: .4rem;
}
.service-card .more::after { content: "→"; transition: transform var(--transition); }
.service-card:hover .more::after { transform: translateX(4px); }
.service-card.dark { background: var(--brown); color: var(--white); }
.service-card.dark h3, .service-card.dark .more { color: var(--white); }
.service-card.dark p { color: rgba(255,255,255,.85); }

/* ---------- Stats band ---------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  text-align: center;
}
.stat .num {
  font-size: clamp(2.4rem, 4vw, 3.4rem);
  font-weight: 800;
  color: var(--gold);
  line-height: 1;
  margin-bottom: .4rem;
}
.stat .lbl { font-size: .9rem; letter-spacing: .1em; text-transform: uppercase; color: rgba(255,255,255,.7); }

/* ---------- Two-col / About ---------- */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}
.split .img { border-radius: var(--radius-md); overflow: hidden; box-shadow: var(--shadow-lg); }
.split img { width:100%; height: 100%; object-fit: cover; }

/* ---------- Feature list ---------- */
.feature-list {
  display: grid; grid-template-columns: repeat(2,1fr); gap: 1rem 2rem;
}
.feature-list li {
  display: flex; gap: .8rem; align-items: flex-start;
  padding: .6rem 0;
  border-bottom: 1px solid rgba(255,255,255,.08);
  font-size: .95rem;
}
.feature-list li::before {
  content:"›"; color: var(--gold); font-weight: 700; font-size: 1.1rem; line-height: 1;
}

/* ---------- Chip / Tag ---------- */
.chip {
  display:inline-flex; align-items:center; gap:.4rem;
  padding: .55rem 1rem;
  background: var(--brown);
  color: var(--white);
  border-radius: 999px;
  font-size: .85rem;
  font-weight: 500;
}
.chip::before { content:"›"; color: var(--gold); font-weight:700; }
.chip-list { display:flex; flex-wrap:wrap; gap:.6rem; }

/* ---------- CTA band ---------- */
.cta-band {
  background: linear-gradient(135deg, #1a1a1a 0%, #0e0e0e 100%);
  color: var(--white);
  text-align: center;
  padding: 5rem 0;
}
.cta-band h2 { color: var(--white); }
.cta-band .accent { color: var(--gold); }

/* ---------- Page hero (interior pages) ---------- */
.page-hero {
  position: relative;
  padding: 13rem 0 5rem;
  color: var(--white);
  background: var(--black);
  overflow: hidden;
}
.page-hero::before {
  content:""; position:absolute; inset:0;
  background-size: cover; background-position: center;
  filter: brightness(.45);
}
.page-hero[data-bg="hero"]::before     { background-image: url('../img/hero-mine.jpg'); }
.page-hero[data-bg="services"]::before { background-image: url('../img/processing.jpg'); }
.page-hero[data-bg="about"]::before    { background-image: url('../img/mine-truck.jpg'); }
.page-hero[data-bg="careers"]::before  { background-image: url('../img/machines.jpg'); }
.page-hero[data-bg="contact"]::before  { background-image: url('../img/hero-mine.jpg'); }
.page-hero .container { position: relative; }
.page-hero h1 { color: var(--white); }
.breadcrumbs { font-size: .85rem; color: rgba(255,255,255,.7); margin-bottom: 1rem; letter-spacing: .08em; text-transform: uppercase; }
.breadcrumbs a { color: var(--gold); }

/* ---------- Forms ---------- */
.form { display: grid; gap: 1rem; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.field label {
  display:block; font-size:.8rem; font-weight:600;
  letter-spacing: .12em; text-transform: uppercase;
  color: var(--grey-500); margin-bottom: .4rem;
}
.field input, .field select, .field textarea {
  width: 100%;
  padding: .85rem 1rem;
  border: 1px solid var(--grey-100);
  border-radius: var(--radius-sm);
  font: inherit;
  background: var(--white);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: 0;
  border-color: var(--gold);
  box-shadow: 0 0 0 3px rgba(244,180,0,.18);
}
.field textarea { min-height: 140px; resize: vertical; }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--black);
  color: rgba(255,255,255,.75);
  padding: 4.5rem 0 2rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 3rem;
  margin-bottom: 3rem;
}
.footer-grid h4 {
  font-size: .85rem; letter-spacing: .15em; text-transform: uppercase;
  color: var(--gold); margin-bottom: 1.2rem;
}
.footer-grid a { display:block; padding: .25rem 0; color: rgba(255,255,255,.75); font-size:.95rem; }
.footer-grid a:hover { color: var(--white); }
.footer-grid .brand img { height: 96px; margin-bottom: 1rem; background:#fff; padding:8px; border-radius:10px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.1);
  padding-top: 1.5rem;
  display:flex; justify-content:space-between; flex-wrap: wrap; gap: 1rem;
  font-size:.85rem; color: rgba(255,255,255,.55);
}

.contact-line {
  display:flex; align-items:center; gap:.6rem;
  padding: .35rem 0;
  font-size: .95rem;
}
.contact-line .ico { color: var(--gold); width: 18px; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .services-grid { grid-template-columns: 1fr 1fr; }
  .stats { grid-template-columns: 1fr 1fr; }
  .split { grid-template-columns: 1fr; gap: 2.5rem; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .feature-list { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  section { padding: 4rem 0; }
  .services-grid { grid-template-columns: 1fr; }
  .stats { grid-template-columns: 1fr 1fr; gap: 1.5rem; }
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
  .form-row { grid-template-columns: 1fr; }
  .menu-toggle { display: flex; }
  .main-nav {
    position: fixed; inset: 0;
    background: var(--black);
    flex-direction: column;
    padding: 7rem 2rem 2rem;
    transform: translateX(100%);
    transition: transform var(--transition);
  }
  .main-nav.open { transform: translateX(0); }
  .main-nav ul { flex-direction: column; align-items: flex-start; gap: 1.2rem; }
  .main-nav a { font-size: 1.4rem; }
  .lang-switch { display: none; }
  .header-cta .btn { display: none; }
  .page-hero { padding: 8rem 0 4rem; }
}