:root {
  --bg-page: #ffffff;
  --bg-surface: #f5f5f7;
  --bg-card: #ffffff;
  --bg-hover: #ebebee;

  --text-primary: #1d1d1f;
  --text-secondary: #333333;
  --text-muted: #86868b;

  --accent-blue: #007aff;
  --accent-blue-hover: #0066d6;
  --accent-green: #34c759;

  --border-light: #e5e5ea;
  --border-medium: #d2d2d7;
  --border-focus: #007aff;

  --shadow-subtle: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.05);
  --shadow-card-hover: 0 8px 30px rgba(0, 0, 0, 0.08);
  --shadow-button: 0 2px 8px rgba(0, 122, 255, 0.2);

  --font-sans:
    'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto,
    sans-serif;
  --font-mono: 'JetBrains Mono', SFMono-Regular, Menlo, monospace;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  --ease-smooth: 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.6;
  scroll-behavior: smooth;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-page);
}

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 2rem;
}

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color var(--ease-smooth);
}

a:hover {
  color: var(--accent-blue-hover);
}

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background-color: var(--bg-surface);
  color: var(--text-primary);
  padding: 0.2rem 0.45rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: 3px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  padding: 1rem 0;
}

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

.brand-logo {
  display: inline-flex;
  align-items: center;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-light);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--accent-green);
}

.header-link {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--ease-smooth);
}

.header-link:hover {
  color: var(--text-primary);
}

.hero-section {
  padding: 7rem 0 5.5rem;
  text-align: center;
}

.hero-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  max-width: 820px;
}

.hero-tag {
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent-blue);
  margin-bottom: 1.25rem;
}

.hero-title {
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  font-weight: 700;
  line-height: 1.12;
  letter-spacing: -0.035em;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
}

.hero-description {
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
  color: var(--text-secondary);
  font-weight: 400;
  line-height: 1.65;
  max-width: 640px;
  margin-bottom: 2.75rem;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  border-radius: var(--radius-full);
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--ease-smooth);
  letter-spacing: -0.01em;
}

.btn-primary {
  background-color: var(--accent-blue);
  color: #ffffff;
  box-shadow: var(--shadow-button);
}

.btn-primary:hover {
  background-color: var(--accent-blue-hover);
  color: #ffffff;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(0, 122, 255, 0.3);
}

.btn-secondary {
  background-color: var(--bg-page);
  color: var(--text-primary);
  border: 1px solid var(--border-medium);
}

.btn-secondary:hover {
  background-color: var(--bg-surface);
  border-color: var(--text-primary);
  color: var(--text-primary);
  transform: translateY(-1px);
}

.github-icon {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
}

.section-tag {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent-blue);
  margin-bottom: 0.6rem;
}

.section-title {
  font-size: clamp(1.75rem, 3.2vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 1.05rem;
  font-weight: 400;
  max-width: 580px;
  margin: 0 auto;
}

.section-environment {
  background-color: var(--bg-surface);
  padding: 6rem 0;
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
}

.cards-layout {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 1.5rem;
  align-items: stretch;
}

.card {
  background-color: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-subtle);
  border: 1px solid rgba(0, 0, 0, 0.04);
  display: flex;
  flex-direction: column;
  transition:
    transform var(--ease-smooth),
    box-shadow var(--ease-smooth);
}

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

.card-featured {
  padding: 2.75rem 2.5rem;
  justify-content: space-between;
}

.card-featured .card-title {
  font-size: 1.65rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.card-featured .card-text {
  color: var(--text-secondary);
  font-size: 1.05rem;
  line-height: 1.7;
  margin-bottom: 2.25rem;
}

.cards-secondary-stack {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.card-compact {
  padding: 1.4rem 1.6rem;
}

.card-compact .card-title {
  font-size: 1.08rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--text-primary);
  margin-bottom: 0.35rem;
}

.card-compact .card-text {
  color: var(--text-secondary);
  font-size: 0.88rem;
  line-height: 1.55;
  margin-bottom: 0.9rem;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.tag {
  font-size: 0.75rem;
  font-weight: 500;
  padding: 0.25rem 0.6rem;
  border-radius: var(--radius-full);
  background-color: var(--bg-surface);
  color: var(--text-secondary);
  border: 1px solid var(--border-light);
}

@media (max-width: 860px) {
  .cards-layout {
    grid-template-columns: 1fr;
  }
}

.section-interactive {
  padding: 6.5rem 0;
  background-color: var(--bg-page);
}

.demo-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 840px) {
  .demo-layout {
    grid-template-columns: 1fr;
  }
}

.demo-card {
  background-color: var(--bg-surface);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  border: 1px solid var(--border-light);
  display: flex;
  flex-direction: column;
}

.demo-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}

.demo-widget-title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--text-primary);
}

.badge-pill {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  background-color: var(--bg-card);
  color: var(--text-secondary);
  border: 1px solid var(--border-light);
}

.counter-display-wrapper {
  text-align: center;
  padding: 1.5rem 0 2.25rem;
}

.counter-value {
  font-size: 5rem;
  font-weight: 700;
  font-family: var(--font-sans);
  color: var(--text-primary);
  line-height: 1;
  letter-spacing: -0.04em;
  transition: transform 0.15s ease-out;
}

.counter-value.pulse {
  transform: scale(1.06);
}

.counter-caption {
  margin-top: 0.6rem;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.counter-controls {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  margin-top: auto;
}

.ctrl-btn {
  padding: 0.75rem 1.35rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--border-medium);
  background-color: var(--bg-card);
  color: var(--text-primary);
  box-shadow: var(--shadow-subtle);
  transition: all var(--ease-smooth);
}

.ctrl-btn:hover {
  transform: translateY(-1px);
  background-color: #ffffff;
  border-color: var(--text-primary);
}

.btn-increment {
  background-color: var(--accent-blue);
  color: #ffffff;
  border-color: var(--accent-blue);
  box-shadow: var(--shadow-button);
}

.btn-increment:hover {
  background-color: var(--accent-blue-hover);
  border-color: var(--accent-blue-hover);
  color: #ffffff;
}

.inspector-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2rem;
}

.inspector-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-light);
  font-size: 0.9rem;
}

.item-label {
  color: var(--text-secondary);
}

.item-value {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--text-primary);
  font-size: 0.88rem;
}

.item-value.highlight-link {
  color: var(--accent-blue);
}

.inspector-action-box {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.btn-outline {
  background-color: var(--bg-card);
  border: 1px solid var(--border-medium);
  color: var(--text-primary);
  padding: 0.6rem 1rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.85rem;
  transition: all var(--ease-smooth);
  box-shadow: var(--shadow-subtle);
}

.btn-outline:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  background-color: #ffffff;
}

.inspector-note {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--border-light);
  background-color: var(--bg-surface);
  padding: 1.75rem 0;
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.footer-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
}

.footer-left {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 0.88rem;
  line-height: 1.2;
}

.footer-project {
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.015em;
}

.footer-sep {
  color: var(--border-medium);
  font-weight: 400;
  user-select: none;
}

.footer-lab {
  color: var(--text-secondary);
  font-weight: 400;
}

.footer-right {
  display: inline-flex;
  align-items: center;
  gap: 0.85rem;
  font-size: 0.85rem;
  line-height: 1.2;
}

.footer-link {
  color: var(--text-secondary);
  font-weight: 500;
  text-decoration: none;
  transition: color var(--ease-smooth);
}

.footer-link:hover {
  color: var(--accent-blue);
}

.footer-dot {
  display: inline-block;
  width: 3.5px;
  height: 3.5px;
  border-radius: 50%;
  background-color: var(--text-muted);
  opacity: 0.6;
  user-select: none;
}

.footer-gemini {
  display: inline-flex;
  align-items: center;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent-blue);
  background-color: rgba(0, 122, 255, 0.08);
  border: 1px solid rgba(0, 122, 255, 0.2);
  padding: 0.3rem 0.85rem;
  border-radius: var(--radius-full);
  letter-spacing: -0.01em;
  line-height: 1.2;
  box-shadow: 0 1px 3px rgba(0, 122, 255, 0.08);
}

@media (max-width: 640px) {
  .hero-section {
    padding: 4.5rem 0 3.5rem;
  }

  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }

  .btn {
    width: 100%;
  }

  .footer-container {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 0.85rem;
  }

  .footer-left,
  .footer-right {
    justify-content: center;
    flex-wrap: wrap;
  }
}