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

:root {
  --color-surface-primary:   #ffffff;
  --color-surface-secondary: #f9fafb;
  --color-surface-tertiary:  #f3f4f6;
  --color-surface-container: #f3f4fb; /* faint blue-violet tint */

  --color-text-primary:   #111827;
  --color-text-secondary: #6b7280;
  --color-text-muted:     #9ca3af;

  --color-border-default: #e5e7eb;
  --color-border-subtle:  #f3f4f6;

  --color-accent:        #2563eb;
  --color-accent-hover:  #1d4ed8;
  --color-accent-subtle: #eff6ff;

  --color-success-bg: #f0fdf4; --color-success-text: #15803d; --color-success-border: #bbf7d0;
  --color-neutral-bg: #f9fafb; --color-neutral-text: #374151; --color-neutral-border: #d1d5db;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-pill: 9999px;

  --elevation-1: 0 1px 2px 0 rgb(0 0 0 / 0.08), 0 1px 3px 1px rgb(0 0 0 / 0.06);
  --elevation-2: 0 1px 2px 0 rgb(0 0 0 / 0.08), 0 2px 6px 2px rgb(0 0 0 / 0.08);
  --elevation-3: 0 4px 8px 3px rgb(0 0 0 / 0.08), 0 1px 3px rgb(0 0 0 / 0.10);

  --ease-standard: cubic-bezier(0.2, 0, 0, 1);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Noto Sans SC', Roboto, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text-primary);
  background: var(--color-surface-secondary);
}

a { color: var(--color-accent); text-decoration: none; }
a:hover { text-decoration: underline; }
button { cursor: pointer; font-family: inherit; }
img, svg { display: block; }

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Top navigation ===== */
.nav {
  height: 64px;
  display: flex;
  align-items: center;
  background: var(--color-surface-primary);
  border-bottom: 1px solid var(--color-border-subtle);
  position: sticky;
  top: 0;
  z-index: 10;
}

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

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text-primary);
}

.nav-logo:hover { text-decoration: none; }

.nav-logo .mark {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-md);
  background: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 14px;
  font-weight: 600;
  font-family: Roboto, sans-serif;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links a {
  font-size: 14px;
  color: var(--color-text-secondary);
  font-weight: 500;
}

.nav-links a:hover { color: var(--color-text-primary); text-decoration: none; }

.nav-links a.cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  background: var(--color-text-primary);
  color: white;
}
.nav-links a.cta:hover { background: #1f2937; text-decoration: none; }

.script-toggle-btn {
  display: inline-flex;
  align-items: center;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--color-border-default);
  background: var(--color-surface-primary);
  color: var(--color-text-secondary);
  font-size: 14px;
  font-weight: 500;
  transition: border-color 200ms var(--ease-standard), color 200ms var(--ease-standard);
}
.script-toggle-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ===== Hero ===== */
.hero {
  background: linear-gradient(180deg, var(--color-surface-container) 0%, var(--color-surface-secondary) 100%);
  padding: 88px 0 72px;
  text-align: center;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 14px;
  border-radius: var(--radius-pill);
  background: var(--color-surface-primary);
  box-shadow: var(--elevation-1);
  color: var(--color-text-secondary);
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 24px;
}

.hero-eyebrow .dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: #16a34a;
}

.hero h1 {
  font-size: 44px;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--color-text-primary);
  max-width: 760px;
  margin: 0 auto 20px;
}

.hero h1 .accent { color: var(--color-accent); }

.hero p.lead {
  font-size: 17px;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto 36px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 44px;
  padding: 0 24px;
  border-radius: var(--radius-pill);
  font-size: 15px;
  font-weight: 500;
  border: none;
  transition: box-shadow 200ms var(--ease-standard), background 200ms var(--ease-standard), transform 200ms var(--ease-standard);
}

.btn-primary {
  background: var(--color-accent);
  color: white;
  box-shadow: var(--elevation-1);
}
.btn-primary:hover {
  background: var(--color-accent-hover);
  box-shadow: var(--elevation-2);
  text-decoration: none;
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--color-surface-primary);
  color: var(--color-text-primary);
  box-shadow: var(--elevation-1);
}
.btn-secondary:hover {
  box-shadow: var(--elevation-2);
  text-decoration: none;
  transform: translateY(-1px);
}

/* ===== Sections ===== */
.section {
  padding: 72px 0;
}

.section-head {
  text-align: center;
  max-width: 620px;
  margin: 0 auto 48px;
}

.section-head .kicker {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 10px;
}

.section-head h2 {
  font-size: 30px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 12px;
}

.section-head p {
  font-size: 15px;
  color: var(--color-text-secondary);
}

/* ===== Tool cards ===== */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

@media (min-width: 720px) {
  .tool-grid { grid-template-columns: repeat(2, 1fr); }
}

.tool-card {
  display: flex;
  flex-direction: column;
  background: var(--color-surface-primary);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--elevation-1);
  transition: box-shadow 220ms var(--ease-standard), transform 220ms var(--ease-standard);
  color: inherit;
  text-decoration: none;
  cursor: pointer;
}

.tool-card:hover { text-decoration: none; }

.tool-card:hover {
  box-shadow: var(--elevation-2);
  transform: translateY(-2px);
}

.tool-card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 18px;
}

.tool-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--color-surface-container);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  font-size: 12px;
  font-weight: 500;
  background: var(--color-success-bg);
  color: var(--color-success-text);
  border: 1px solid var(--color-success-border);
  white-space: nowrap;
}

.tool-card h3 {
  font-size: 18px;
  font-weight: 500;
  color: var(--color-text-primary);
  margin-bottom: 4px;
}

.tool-card .tool-name-en {
  font-size: 13px;
  color: var(--color-text-muted);
  font-family: Roboto, sans-serif;
  margin-bottom: 12px;
}

.tool-card p.headline {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text-primary);
  line-height: 1.5;
  margin-bottom: 8px;
}

.tool-card p.desc {
  font-size: 13px;
  color: var(--color-text-muted);
  flex: 1;
  margin-bottom: 20px;
}

.tool-card .tool-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-accent);
}

.tool-card .tool-link svg {
  transition: transform 200ms var(--ease-standard);
}

.tool-card:hover .tool-link svg {
  transform: translateX(3px);
}

.tool-card.placeholder {
  background: transparent;
  box-shadow: none;
  border: 1.5px dashed var(--color-border-default);
  align-items: center;
  text-align: center;
  cursor: default;
  justify-content: center;
  color: var(--color-text-muted);
}

.tool-card.placeholder .tool-icon {
  background: transparent;
  color: var(--color-text-muted);
  margin: 0 auto 14px;
}

.tool-card.placeholder p {
  font-size: 14px;
}

/* ===== Principles ===== */
.principles {
  background: var(--color-surface-primary);
  border-top: 1px solid var(--color-border-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
}

@media (max-width: 720px) {
  .tool-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 32px; }
  .giant-card { grid-template-columns: 1fr; }
  .giant-arrow { transform: rotate(90deg); margin: 4px auto; }
}

.giant-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 40px;
}

.giant-card {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 28px;
  background: var(--color-surface-primary);
  border-radius: var(--radius-lg);
  box-shadow: var(--elevation-1);
  padding: 36px;
}

.giant-col h3 {
  font-size: 18px;
  font-weight: 500;
  margin: 12px 0 8px;
}

.giant-col p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.giant-arrow {
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
}

.badge-neutral {
  background: var(--color-neutral-bg);
  color: var(--color-neutral-text);
  border: 1px solid var(--color-neutral-border);
}

.badge-accent {
  background: var(--color-accent-subtle);
  color: var(--color-accent);
  border: 1px solid #bfdbfe;
}

.principle-strip {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  background: var(--color-surface-container);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
}

.principle-strip-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--color-surface-primary);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--elevation-1);
}

.principle-strip h3 {
  font-size: 17px;
  font-weight: 500;
  margin-bottom: 6px;
}

.principle-strip p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

@media (max-width: 640px) {
  .principle-strip { flex-direction: column; }
}

/* ===== About / CTA band ===== */
.cta-band {
  background: var(--color-text-primary);
  border-radius: var(--radius-lg);
  padding: 56px 40px;
  text-align: center;
  color: white;
  margin: 0 24px;
  max-width: 1032px;
  margin: 0 auto;
}

.cta-band h2 {
  font-size: 26px;
  font-weight: 600;
  margin-bottom: 12px;
}

.cta-band p {
  font-size: 15px;
  color: #d1d5db;
  max-width: 520px;
  margin: 0 auto 28px;
}

.cta-band .btn-primary {
  background: white;
  color: var(--color-text-primary);
}
.cta-band .btn-primary:hover {
  background: #f3f4f6;
}

/* ===== Footer ===== */
.footer {
  padding: 56px 0 40px;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 32px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--color-border-subtle);
  margin-bottom: 24px;
}

.footer-brand .nav-logo { margin-bottom: 12px; }

.footer-brand p {
  font-size: 13px;
  color: var(--color-text-muted);
  max-width: 280px;
}

.footer-links {
  display: flex;
  gap: 56px;
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text-primary);
  margin-bottom: 14px;
}

.footer-col a {
  display: block;
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 10px;
}

.footer-col a:hover { color: var(--color-text-primary); text-decoration: none; }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: var(--color-text-muted);
}

.footer-bottom .license {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}