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

:root {
  --bg: #fafaf9;
  --bg-alt: #f5f5f4;
  --surface: #ffffff;
  --border: #e7e5e4;
  --text: #1c1917;
  --text-secondary: #44403c;
  --text-muted: #78716c;
  --accent: #0f766e;
  --accent-hover: #0d9488;
  --accent-light: #f0fdfa;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
}

/* === Nav === */
.nav {
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
}

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

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.01em;
}

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

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  padding: 8px 20px;
  border: 1px solid var(--accent);
  border-radius: 6px;
  transition: background 0.2s, color 0.2s;
}

.nav-link:hover {
  background: var(--accent);
  color: #ffffff;
}

/* === Hero === */
.hero {
  padding: 120px 0 100px;
}

.hero-label {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-light);
  padding: 6px 14px;
  border-radius: 20px;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(2rem, 4.5vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.025em;
  color: var(--text);
  margin-bottom: 20px;
  max-width: 640px;
}

.hero-sub {
  font-size: 1.15rem;
  color: var(--text-secondary);
  max-width: 520px;
  line-height: 1.7;
  margin-bottom: 36px;
}

.btn-primary {
  display: inline-block;
  font-size: 0.95rem;
  font-weight: 500;
  color: #ffffff;
  background: var(--accent);
  padding: 12px 28px;
  border-radius: 6px;
  text-decoration: none;
  transition: background 0.2s;
}

.btn-primary:hover {
  background: var(--accent-hover);
}

/* === Sections === */
.section {
  padding: 80px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-header {
  margin-bottom: 48px;
}

.section-header h2 {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  margin-bottom: 12px;
}

.section-header p {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 540px;
}

/* === Cards === */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 24px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 32px 28px;
}

.card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
}

.card p {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* === Process Steps === */
.process-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 24px;
}

.step {
  text-align: center;
  padding: 28px 20px;
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--accent-light);
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 14px;
}

.step-label {
  display: block;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.step-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* === Target List === */
.target-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.target-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px 0;
}

.target-icon {
  flex-shrink: 0;
  width: 8px;
  height: 8px;
  margin-top: 8px;
  border-radius: 50%;
  background: var(--accent);
}

.target-item p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* === About === */
.about-text {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  line-height: 1.75;
}

/* === Contact === */
.section-contact {
  text-align: center;
  padding: 100px 0;
}

.section-contact h2 {
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.section-contact p {
  font-size: 1.05rem;
  color: var(--text-muted);
  margin-bottom: 28px;
}

/* === Footer === */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* === Fade-in Animation === */
.fade-in {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* === Responsive === */
@media (max-width: 600px) {
  .hero {
    padding: 80px 0 60px;
  }

  .section {
    padding: 60px 0;
  }

  .process-steps {
    grid-template-columns: 1fr 1fr;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .target-grid {
    grid-template-columns: 1fr;
  }
}