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

:root {
  --bg-page: #E8E9EB;
  --text-primary: #1A1A1A;
  --text-secondary: #666666;
  --text-tertiary: #999999;
  --text-on-card: #FFFFFF;
  --divider: #E0E0E0;
  --bg-polar: #3D5A80;

  --font-mono: 'Geist Mono', 'SF Mono', 'Fira Code', monospace;
  --font-sans: 'Inter', 'Geist', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

/* ===== Header ===== */
.site-header {
  width: 100%;
}

.header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 80px;
  max-width: 1440px;
  margin: 0 auto;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  width: 24px;
  height: 24px;
  border-radius: 6px;
}

.logo-text {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 200;
  letter-spacing: 2px;
  color: var(--text-primary);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 1px;
  color: var(--text-primary);
  transition: opacity 0.2s;
}

.nav-link:hover {
  opacity: 0.6;
}

.header-rule {
  height: 1px;
  background: var(--divider);
  width: 100%;
}

/* ===== Product Hero ===== */
.product-hero {
  max-width: 1440px;
  margin: 0 auto;
  padding: 64px 80px 80px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.micro-label {
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 3px;
  color: var(--text-tertiary);
  text-transform: uppercase;
}

.product-hero-title {
  font-family: var(--font-mono);
  font-size: 72px;
  font-weight: 200;
  line-height: 0.95;
  color: var(--text-primary);
}

.product-hero-tagline {
  font-size: 18px;
  font-weight: 400;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 700px;
}

.hero-cta {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--text-primary);
  display: inline-block;
  transition: opacity 0.2s;
}

.hero-cta:hover {
  opacity: 0.6;
}

/* ===== App Screenshots ===== */
.app-screenshots {
  max-width: 1440px;
  margin: 0 auto;
  padding: 64px 0 80px;
}

.screenshots-header {
  padding: 0 80px;
  margin-bottom: 40px;
}

.app-badge {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  padding: 12px 20px 12px 12px;
  background: var(--text-primary);
  border-radius: 16px;
}

.app-badge-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
}

.app-badge-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.app-badge-name {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 400;
  color: var(--text-on-card);
  letter-spacing: 0.5px;
}

.app-badge-sub {
  font-size: 11px;
  color: var(--text-on-card);
  opacity: 0.5;
}

.app-badge-download {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.5px;
  color: var(--text-primary);
  background: var(--text-on-card);
  padding: 6px 20px;
  border-radius: 20px;
  margin-left: 8px;
  transition: opacity 0.2s;
}

.app-badge-download:hover {
  opacity: 0.85;
}

.screenshots-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.screenshots-scroll::-webkit-scrollbar {
  display: none;
}

.screenshots-track {
  display: flex;
  gap: 20px;
  padding: 0 80px;
  width: max-content;
}

.screenshot-item {
  flex-shrink: 0;
  width: 260px;
  border-radius: 24px;
  overflow: hidden;
  background: #F5F5F5;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
}

.screenshot-item img {
  width: 100%;
  height: auto;
  display: block;
}

/* ===== Divider ===== */
.divider {
  height: 1px;
  background: var(--divider);
  width: 100%;
}

/* ===== Product Intro ===== */
.product-intro {
  max-width: 1440px;
  margin: 0 auto;
  padding: 64px 80px;
}

.product-intro-text {
  font-size: 17px;
  font-weight: 400;
  line-height: 1.8;
  color: var(--text-secondary);
  max-width: 800px;
}

/* ===== Section Headers ===== */
.product-section-header {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 48px;
}

.product-section-title {
  font-family: var(--font-mono);
  font-size: 48px;
  font-weight: 200;
  line-height: 1.1;
  color: var(--text-primary);
}

/* ===== Features ===== */
.product-features {
  max-width: 1440px;
  margin: 0 auto;
  padding: 80px 80px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 48px 40px;
}

.feature-card {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.feature-number {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 200;
  color: var(--text-tertiary);
  letter-spacing: 2px;
}

.feature-title {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 400;
  line-height: 1.3;
  color: var(--text-primary);
}

.feature-desc {
  font-size: 14px;
  font-weight: 400;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* ===== How It Works ===== */
.product-how {
  max-width: 1440px;
  margin: 0 auto;
  padding: 80px 80px;
}

.how-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.how-step {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 32px;
  background-color: var(--text-primary);
  color: var(--text-on-card);
  border-radius: 4px;
}

.step-number {
  font-family: var(--font-mono);
  font-size: 36px;
  font-weight: 200;
  opacity: 0.3;
}

.step-title {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 200;
}

.step-desc {
  font-size: 14px;
  font-weight: 400;
  line-height: 1.7;
  opacity: 0.7;
}

/* ===== Use Cases ===== */
.product-usecases {
  max-width: 1440px;
  margin: 0 auto;
  padding: 80px 80px;
}

.usecases-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}

.usecase-card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 32px 24px;
  border: 1px solid var(--divider);
  border-radius: 4px;
}

.usecase-role {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 400;
  color: var(--text-primary);
}

.usecase-desc {
  font-size: 14px;
  font-weight: 400;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* ===== Comparison Table ===== */
.product-comparison {
  max-width: 1440px;
  margin: 0 auto;
  padding: 80px 80px;
}

.comparison-table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.comparison-table thead {
  background: var(--text-primary);
  color: var(--text-on-card);
}

.comparison-table th {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 12px;
  letter-spacing: 1px;
  text-align: left;
  padding: 16px 24px;
}

.comparison-table td {
  padding: 16px 24px;
  border-bottom: 1px solid var(--divider);
  line-height: 1.6;
  color: var(--text-secondary);
}

.comparison-table .comparison-feature {
  font-weight: 500;
  color: var(--text-primary);
}

.comparison-table tbody tr:hover {
  background: rgba(0, 0, 0, 0.02);
}

/* ===== Stats ===== */
.product-stats {
  max-width: 1440px;
  margin: 0 auto;
  padding: 64px 80px;
}

.stats-grid {
  display: flex;
  justify-content: center;
  gap: 80px;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.stat-value {
  font-family: var(--font-mono);
  font-size: 48px;
  font-weight: 200;
  line-height: 1;
  color: var(--text-primary);
}

.stat-label {
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 2px;
  color: var(--text-tertiary);
  text-transform: uppercase;
}

/* ===== FAQ ===== */
.faq-section {
  max-width: 1440px;
  margin: 0 auto;
  padding: 80px 80px;
}

.faq-header {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 48px;
}

.faq-title {
  font-family: var(--font-mono);
  font-size: 48px;
  font-weight: 200;
  line-height: 1.1;
  color: var(--text-primary);
}

.faq-list {
  display: flex;
  flex-direction: column;
}

.faq-item {
  border-top: 1px solid var(--divider);
  padding: 24px 0;
}

.faq-item:last-child {
  border-bottom: 1px solid var(--divider);
}

.faq-question {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 400;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-question::-webkit-details-marker {
  display: none;
}

.faq-question::after {
  content: '+';
  font-size: 24px;
  font-weight: 200;
  transition: transform 0.2s;
}

details[open] .faq-question::after {
  content: '\2212';
}

.faq-answer {
  margin-top: 16px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 800px;
}

/* ===== CTA Section ===== */
.product-cta-section {
  max-width: 1440px;
  margin: 0 auto;
  padding: 80px 80px;
  text-align: center;
}

.product-cta-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.product-cta-title {
  font-family: var(--font-mono);
  font-size: 40px;
  font-weight: 200;
  line-height: 1.1;
  color: var(--text-primary);
}

.product-cta-desc {
  font-size: 16px;
  font-weight: 400;
  line-height: 1.6;
  color: var(--text-secondary);
}

.product-cta-link {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--text-primary);
  transition: opacity 0.2s;
}

.product-cta-link:hover {
  opacity: 0.6;
}

/* ===== Footer ===== */
.site-footer {
  background-color: var(--text-primary);
  color: var(--text-on-card);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  padding: 64px 80px;
  max-width: 1440px;
  margin: 0 auto;
}

.footer-left {
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 360px;
}

.footer-brand {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 200;
  letter-spacing: 2px;
}

.footer-tagline {
  font-size: 14px;
  line-height: 1.6;
  opacity: 0.5;
  white-space: pre-line;
}

.footer-nav {
  display: flex;
  gap: 80px;
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col-title {
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 3px;
  margin-bottom: 4px;
}

.footer-link {
  font-size: 13px;
  font-weight: 400;
  opacity: 0.5;
  transition: opacity 0.2s;
}

.footer-link:hover {
  opacity: 0.8;
}

.footer-divider {
  height: 1px;
  background: #FFFFFF;
  opacity: 0.1;
  max-width: 1440px;
  margin: 0 auto;
}

.copyright-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 80px;
  max-width: 1440px;
  margin: 0 auto;
}

.copyright-text,
.copyright-right {
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 2px;
  opacity: 0.3;
}

/* ===== Legal Pages (Privacy, Terms, Help) ===== */
.legal-hero {
  max-width: 1440px;
  margin: 0 auto;
  padding: 48px 80px 64px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.legal-heading {
  font-family: var(--font-mono);
  font-size: 64px;
  font-weight: 200;
  line-height: 0.95;
  color: var(--text-primary);
}

.legal-intro {
  font-size: 17px;
  font-weight: 400;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 700px;
}

.legal-section {
  max-width: 1440px;
  margin: 0 auto;
  padding: 64px 80px;
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 80px;
}

.legal-section-header {
  display: flex;
  flex-direction: column;
  gap: 12px;
  position: sticky;
  top: 32px;
  align-self: start;
}

.legal-section-number {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 200;
  color: var(--text-tertiary);
  letter-spacing: 2px;
}

.legal-section-title {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 200;
  line-height: 1.3;
  color: var(--text-primary);
}

.legal-items {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.legal-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.legal-item-label {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 400;
  color: var(--text-primary);
  letter-spacing: 0.5px;
}

.legal-item-text {
  font-size: 15px;
  font-weight: 400;
  line-height: 1.8;
  color: var(--text-secondary);
}

.legal-divider {
  height: 1px;
  background: var(--divider);
  max-width: 1440px;
  margin: 0 auto;
  margin-left: 80px;
  margin-right: 80px;
}

/* ===== Support / Help Page ===== */
.support-channels {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 80px 80px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.support-channel {
  display: flex;
  flex-direction: column;
  gap: 24px;
  padding: 40px 32px;
  background: var(--text-primary);
  color: var(--text-on-card);
  border-radius: 4px;
}

.channel-icon {
  font-family: var(--font-mono);
  font-size: 36px;
  font-weight: 200;
  opacity: 0.3;
}

.channel-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.channel-title {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 200;
}

.channel-desc {
  font-size: 14px;
  font-weight: 400;
  line-height: 1.7;
  opacity: 0.7;
}

.channel-detail {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 400;
  letter-spacing: 0.5px;
  opacity: 0.9;
  margin-top: 4px;
}

.channel-response {
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 2px;
  text-transform: uppercase;
  opacity: 0.4;
}

/* ===== Responsive ===== */

/* Tablet */
@media (max-width: 1024px) {
  .header-bar {
    padding: 16px 40px;
  }

  .product-hero {
    padding: 48px 40px 60px;
  }

  .product-hero-title {
    font-size: 48px;
  }

  .product-intro {
    padding: 48px 40px;
  }

  .product-features {
    padding: 60px 40px;
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .product-how {
    padding: 60px 40px;
  }

  .how-steps {
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }

  .product-usecases {
    padding: 60px 40px;
  }

  .usecases-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .product-comparison {
    padding: 60px 40px;
  }

  .product-stats {
    padding: 48px 40px;
  }

  .stats-grid {
    gap: 48px;
  }

  .stat-value {
    font-size: 36px;
  }

  .faq-section {
    padding: 60px 40px;
  }

  .faq-title {
    font-size: 36px;
  }

  .product-cta-section {
    padding: 60px 40px;
  }

  .product-section-title {
    font-size: 36px;
  }

  .product-cta-title {
    font-size: 32px;
  }

  .screenshots-header {
    padding: 0 40px;
  }

  .screenshots-track {
    padding: 0 40px;
    gap: 16px;
  }

  .screenshot-item {
    width: 220px;
    border-radius: 20px;
  }

  .app-screenshots {
    padding: 48px 0 60px;
  }

  .footer-content {
    padding: 48px 40px;
    flex-direction: column;
    gap: 48px;
  }

  .footer-nav {
    gap: 40px;
  }

  .copyright-bar {
    padding: 24px 40px;
  }

  .legal-hero {
    padding: 36px 40px 48px;
  }

  .legal-heading {
    font-size: 44px;
  }

  .legal-section {
    padding: 48px 40px;
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .legal-section-header {
    position: static;
  }

  .legal-divider {
    margin-left: 40px;
    margin-right: 40px;
  }

  .support-channels {
    padding: 0 40px 60px;
    grid-template-columns: 1fr;
    gap: 20px;
  }
}

/* Mobile */
@media (max-width: 640px) {
  .header-bar {
    padding: 12px 20px;
  }

  .main-nav {
    display: none;
  }

  .product-hero {
    padding: 24px 20px 48px;
  }

  .product-hero-title {
    font-size: 32px;
  }

  .product-hero-tagline {
    font-size: 15px;
  }

  .product-intro {
    padding: 32px 20px;
  }

  .product-intro-text {
    font-size: 15px;
  }

  .product-features {
    padding: 40px 20px;
  }

  .features-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .product-how {
    padding: 40px 20px;
  }

  .how-steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .product-usecases {
    padding: 40px 20px;
  }

  .usecases-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .product-comparison {
    padding: 40px 20px;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 12px 16px;
    font-size: 13px;
  }

  .product-stats {
    padding: 32px 20px;
  }

  .stats-grid {
    gap: 32px;
  }

  .stat-value {
    font-size: 28px;
  }

  .stat-label {
    font-size: 10px;
  }

  .faq-section {
    padding: 40px 20px;
  }

  .faq-title {
    font-size: 28px;
  }

  .faq-question {
    font-size: 15px;
  }

  .product-cta-section {
    padding: 40px 20px;
  }

  .product-section-title {
    font-size: 28px;
  }

  .product-cta-title {
    font-size: 24px;
  }

  .screenshots-header {
    padding: 0 20px;
  }

  .screenshots-track {
    padding: 0 20px;
    gap: 12px;
  }

  .screenshot-item {
    width: 180px;
    border-radius: 16px;
  }

  .app-screenshots {
    padding: 32px 0 48px;
  }

  .screenshots-header {
    margin-bottom: 24px;
  }

  .app-badge {
    gap: 12px;
    padding: 10px 16px 10px 10px;
    border-radius: 14px;
  }

  .app-badge-icon {
    width: 40px;
    height: 40px;
    border-radius: 10px;
  }

  .footer-content {
    padding: 40px 20px;
  }

  .footer-nav {
    flex-direction: column;
    gap: 32px;
  }

  .copyright-bar {
    padding: 16px 20px;
    flex-direction: column;
    gap: 8px;
  }

  .legal-hero {
    padding: 24px 20px 36px;
  }

  .legal-heading {
    font-size: 32px;
  }

  .legal-intro {
    font-size: 15px;
  }

  .legal-section {
    padding: 32px 20px;
    gap: 24px;
  }

  .legal-section-title {
    font-size: 20px;
  }

  .legal-divider {
    margin-left: 20px;
    margin-right: 20px;
  }

  .support-channels {
    padding: 0 20px 40px;
  }

  .support-channel {
    padding: 28px 24px;
  }
}