/* ============================================================
   ZS RECYCLING — Global Styles
   ============================================================ */

/* ---- CSS Variables ---- */
:root {
  --color-bg:          #0a1628;
  --color-bg-mid:      #0d1e38;
  --color-bg-card:     #111f36;
  --color-surface:     #1c2f4a;
  --color-border:      rgba(255, 255, 255, 0.08);
  --color-blue:        #1d6fa4;
  --color-blue-light:  #2a8fd1;
  --color-blue-glow:   rgba(29, 111, 164, 0.35);
  --color-silver:      #9aa5b4;
  --color-silver-light:#c8d0da;
  --color-white:       #ffffff;
  --color-text:        #d4dce8;
  --color-text-muted:  #7a8fa6;
  --color-accent:      #4fc3f7;

  --font-sans:   'Inter', 'Segoe UI', Arial, sans-serif;
  --font-mono:   'JetBrains Mono', 'Courier New', monospace;

  --nav-height:  72px;
  --radius-sm:   6px;
  --radius-md:   12px;
  --radius-lg:   20px;

  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 40px rgba(29, 111, 164, 0.2);

  --transition:  all 0.3s ease;
}

/* ---- 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-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

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

ul {
  list-style: none;
}

/* ---- Typography ---- */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-white);
  font-weight: 700;
  line-height: 1.2;
}

h1 { font-size: clamp(2rem, 4vw, 3.25rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.25rem); }
h3 { font-size: clamp(1.125rem, 2vw, 1.5rem); }
h4 { font-size: 1.125rem; }

p {
  color: var(--color-text);
  font-size: 1rem;
  line-height: 1.75;
}

.eyebrow {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.section-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: 0.5rem;
}

/* ---- Layout ---- */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 2rem;
}

section {
  padding: 6rem 0;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.8rem 1.75rem;
  border-radius: 50px;
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-blue);
  color: var(--color-white);
  box-shadow: 0 4px 16px var(--color-blue-glow);
}

.btn-primary:hover {
  background: var(--color-blue-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(29, 111, 164, 0.5);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.06);
  color: var(--color-white);
  border: 1px solid rgba(255, 255, 255, 0.18);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: var(--color-blue-light);
  border: 1.5px solid var(--color-blue);
}

.btn-outline:hover {
  background: var(--color-blue);
  color: var(--color-white);
  transform: translateY(-2px);
}

/* ---- Cards ---- */
.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  box-shadow: var(--shadow-card);
  transition: var(--transition);
}

.card:hover {
  border-color: rgba(29, 111, 164, 0.4);
  transform: translateY(-4px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

/* ---- Section Headers ---- */
.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 4rem;
}

.section-header h2 {
  margin-bottom: 1rem;
}

.section-header p {
  color: var(--color-text-muted);
  font-size: 1.05rem;
}

.divider {
  width: 48px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-blue), var(--color-accent));
  border-radius: 2px;
  margin: 1rem auto 1.5rem;
}

/* ============================================================
   NAVIGATION
   ============================================================ */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--nav-height);
  background: rgba(10, 22, 40, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.site-nav.scrolled {
  background: rgba(10, 22, 40, 0.98);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
}

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

/* Logo */
.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--color-white);
}

.nav-logo .logo-zs {
  color: var(--color-accent);
}

.nav-logo svg {
  width: 32px;
  height: 32px;
}

/* Nav links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-silver-light);
  transition: color 0.2s ease;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-blue-light);
  transition: width 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-white);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

/* Nav actions */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-actions .btn {
  padding: 0.55rem 1.25rem;
  font-size: 0.8rem;
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-white);
  border-radius: 2px;
  transition: all 0.3s ease;
  transform-origin: center;
}

.hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile nav overlay */
.mobile-nav {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(10, 22, 40, 0.98);
  backdrop-filter: blur(12px);
  z-index: 999;
  flex-direction: column;
  padding: 2.5rem 2rem;
  gap: 1.5rem;
  overflow-y: auto;
}

.mobile-nav.open {
  display: flex;
}

.mobile-nav a {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-silver-light);
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--color-border);
  transition: color 0.2s ease;
}

.mobile-nav a:hover {
  color: var(--color-white);
}

.mobile-nav .btn {
  margin-top: 1rem;
  text-align: center;
  justify-content: center;
  width: 100%;
}

/* ============================================================
   CERTIFICATION BADGES
   ============================================================ */
.cert-strip {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.cert-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.9rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 50px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--color-silver-light);
  white-space: nowrap;
}

.cert-badge::before {
  content: '✓';
  color: var(--color-accent);
  font-size: 0.75rem;
}

/* ============================================================
   PAGE HERO (inner pages)
   ============================================================ */
.page-hero {
  padding: calc(var(--nav-height) + 4rem) 0 4rem;
  background: linear-gradient(135deg, var(--color-bg) 0%, var(--color-bg-mid) 100%);
  border-bottom: 1px solid var(--color-border);
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 60% at 80% 50%, rgba(29, 111, 164, 0.12) 0%, transparent 70%);
  pointer-events: none;
}

.page-hero-content {
  position: relative;
  z-index: 1;
}

.page-hero h1 {
  margin: 0.5rem 0 1rem;
}

.page-hero p {
  max-width: 600px;
  color: var(--color-text-muted);
  font-size: 1.1rem;
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  background: #060f1e;
  border-top: 1px solid var(--color-border);
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 3rem;
  padding-bottom: 3rem;
  border-bottom: 1px solid var(--color-border);
}

.footer-brand .nav-logo {
  margin-bottom: 1rem;
}

.footer-brand p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  max-width: 280px;
  margin-bottom: 1.5rem;
}

.footer-col h4 {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-silver);
  margin-bottom: 1.25rem;
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.footer-col ul li a {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

.footer-col ul li a:hover {
  color: var(--color-white);
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  margin-bottom: 0.85rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.footer-contact-item a {
  color: var(--color-text-muted);
  transition: color 0.2s;
}

.footer-contact-item a:hover {
  color: var(--color-accent);
}

.footer-contact-item .icon {
  color: var(--color-blue-light);
  flex-shrink: 0;
  margin-top: 2px;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  gap: 1rem;
  flex-wrap: wrap;
}

.footer-bottom p {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.footer-bottom-links {
  display: flex;
  gap: 1.5rem;
}

.footer-bottom-links a {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

.footer-bottom-links a:hover {
  color: var(--color-white);
}

/* ============================================================
   UTILITIES
   ============================================================ */
.text-center { text-align: center; }
.text-accent  { color: var(--color-accent); }
.text-muted   { color: var(--color-text-muted); }
.mt-1  { margin-top: 0.5rem; }
.mt-2  { margin-top: 1rem; }
.mt-3  { margin-top: 1.5rem; }
.mt-4  { margin-top: 2rem; }
.mb-1  { margin-bottom: 0.5rem; }
.mb-2  { margin-bottom: 1rem; }
.mb-3  { margin-bottom: 1.5rem; }
.mb-4  { margin-bottom: 2rem; }

/* Icon sizes */
.icon-sm { width: 16px; height: 16px; }
.icon-md { width: 24px; height: 24px; }
.icon-lg { width: 36px; height: 36px; }
.icon-xl { width: 56px; height: 56px; }