/* ============================================
   TuTu Earth — Global Styles
   AI-Powered Soil & Environmental Protection
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Outfit:wght@400;500;600;700;800&display=swap');

/* ---------- Design Tokens ---------- */
:root {
  --color-bg: #0a0f0d;
  --color-bg-alt: #111a16;
  --color-bg-card: rgba(16, 32, 24, 0.6);
  --color-surface: rgba(255, 255, 255, 0.04);
  --color-border: rgba(255, 255, 255, 0.08);

  --color-primary: #22c55e;
  --color-primary-light: #4ade80;
  --color-primary-dark: #16a34a;
  --color-primary-glow: rgba(34, 197, 94, 0.25);

  --color-accent: #06b6d4;
  --color-accent-glow: rgba(6, 182, 212, 0.2);

  --color-text: #f0fdf4;
  --color-text-secondary: #a3b8b0;
  --color-text-muted: #6b7f76;

  --font-display: 'Outfit', sans-serif;
  --font-body: 'Inter', sans-serif;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-glow: 0 0 40px var(--color-primary-glow);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);

  --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

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

body {
  font-family: var(--font-body);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a {
  color: var(--color-primary-light);
  text-decoration: none;
  transition: color var(--transition-base);
}
a:hover { color: var(--color-primary); }

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

ul, ol { list-style: none; }

/* ---------- Layout ---------- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
  position: relative;
}

.section-label {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: 12px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.section-label::before {
  content: '';
  width: 24px;
  height: 2px;
  background: var(--color-primary);
  border-radius: 2px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  color: var(--color-text);
}

.section-desc {
  font-size: 1.1rem;
  color: var(--color-text-secondary);
  max-width: 640px;
  line-height: 1.8;
}

/* ---------- Navigation ---------- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: all var(--transition-base);
  background: transparent;
}

.navbar.scrolled {
  background: rgba(10, 15, 13, 0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  padding: 10px 0;
}

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

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.35rem;
  color: var(--color-text);
}
.nav-logo img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav-links a {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition-base);
  position: relative;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition-base);
  border-radius: 2px;
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--color-text);
}
.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-cta {
  background: var(--color-primary) !important;
  color: var(--color-bg) !important;
  padding: 10px 22px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.85rem;
  transition: all var(--transition-base) !important;
}
.nav-cta::after { display: none !important; }
.nav-cta:hover {
  background: var(--color-primary-light) !important;
  transform: translateY(-1px);
  box-shadow: var(--shadow-glow);
}

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}
.nav-hamburger span {
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition-base);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all var(--transition-base);
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-bg);
}
.btn-primary:hover {
  background: var(--color-primary-light);
  color: var(--color-bg);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.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);
  transform: translateY(-2px);
}

/* ---------- Cards ---------- */
.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 36px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all var(--transition-base);
}
.card:hover {
  border-color: rgba(34, 197, 94, 0.2);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-primary-glow), transparent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.card h3 {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.card p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ---------- Grid ---------- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

/* ---------- Stats ---------- */
.stat-number {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 800;
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.1;
}
.stat-label {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-top: 6px;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--color-bg-alt);
  border-top: 1px solid var(--color-border);
  padding: 60px 0 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand p {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  margin-top: 16px;
  max-width: 300px;
  line-height: 1.7;
}

.footer-col h4 {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--color-text);
}
.footer-col a {
  display: block;
  color: var(--color-text-muted);
  font-size: 0.88rem;
  padding: 5px 0;
  transition: color var(--transition-base);
}
.footer-col a:hover {
  color: var(--color-primary-light);
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--color-text-muted);
}

/* ---------- Hero ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 100px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.35;
}
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(10, 15, 13, 0.3) 0%,
    rgba(10, 15, 13, 0.7) 50%,
    var(--color-bg) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 700px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 100px;
  padding: 8px 18px;
  font-size: 0.82rem;
  color: var(--color-primary-light);
  font-weight: 500;
  margin-bottom: 28px;
  animation: fadeInUp 0.8s ease both;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 6vw, 4.5rem);
  font-weight: 900;
  line-height: 1.08;
  margin-bottom: 24px;
  animation: fadeInUp 0.8s ease 0.1s both;
}
.hero h1 .highlight {
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 36px;
  animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-actions {
  display: flex;
  gap: 16px;
  animation: fadeInUp 0.8s ease 0.3s both;
}

/* ---------- Page Header ---------- */
.page-header {
  padding: 160px 0 80px;
  text-align: center;
  position: relative;
  background: linear-gradient(180deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
}
.page-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 400px;
  background: radial-gradient(circle, var(--color-primary-glow), transparent 70%);
  pointer-events: none;
  opacity: 0.4;
}

.page-header h1 {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 5vw, 3.8rem);
  font-weight: 900;
  margin-bottom: 16px;
  position: relative;
}
.page-header .subtitle {
  font-size: 1.15rem;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
  position: relative;
}

/* ---------- Image Container ---------- */
.img-container {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border);
}
.img-container img {
  width: 100%;
  transition: transform var(--transition-base);
}
.img-container:hover img {
  transform: scale(1.03);
}

/* ---------- Contact Form ---------- */
.form-group {
  margin-bottom: 20px;
}
.form-group label {
  display: block;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}
.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 14px 18px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 0.95rem;
  transition: all var(--transition-base);
  outline: none;
}
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-glow);
}
.form-group textarea {
  min-height: 140px;
  resize: vertical;
}

/* ---------- Animations ---------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.6s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Glow orbs background ---------- */
.glow-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  pointer-events: none;
  opacity: 0.15;
}
.glow-orb-green {
  background: var(--color-primary);
}
.glow-orb-cyan {
  background: var(--color-accent);
}

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .section { padding: 64px 0; }

  .nav-links { display: none; }
  .nav-hamburger { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(10, 15, 13, 0.98);
    backdrop-filter: blur(20px);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--color-border);
  }

  .hero { min-height: auto; padding: 140px 0 80px; }
  .hero h1 { font-size: 2.4rem; }
  .hero-actions { flex-direction: column; }

  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; gap: 12px; text-align: center; }

  .page-header { padding: 120px 0 60px; }
}