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

:root {
  --bg: #f5f5f0;
  --surface: #ffffff;
  --text: #4A4A4A;
  --text-secondary: #9B9B9B;
  --border: #EBE9E4;
  --accent: #7A8C99;
  --accent-text: #ffffff;
  --label-accent: #8E9775;
  --header-border: #F5F5F5;
  --section-alt-bg: #ffffff;
  --max-width: 960px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 16px;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--surface);
  border-bottom: 1px solid var(--header-border);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text);
  font-weight: 600;
  font-size: 1.125rem;
}

.brand:hover {
  text-decoration: none;
  color: var(--accent);
}

.brand-icon {
  display: flex;
  color: var(--accent);
}

.nav {
  display: flex;
  gap: 24px;
}

.nav a {
  color: var(--text);
  font-size: 0.9375rem;
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 0.9375rem;
  font-weight: 500;
  cursor: pointer;
  border: 1px solid transparent;
  transition: background 0.2s, color 0.2s;
}

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

.btn-primary:hover {
  background: #6a7a86;
  text-decoration: none;
}

.btn-outline {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}

.btn-outline:hover {
  background: var(--accent);
  color: var(--accent-text);
  text-decoration: none;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 1rem;
}

/* Hero */
.hero {
  padding: 64px 24px 80px;
  text-align: center;
  background: var(--surface);
}

.hero-inner {
  max-width: 640px;
  margin: 0 auto;
}

.hero-badge {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.hero-title {
  font-size: 2rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--text);
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 1.0625rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
  line-height: 1.7;
}

/* Section common */
.section-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 16px;
  text-align: center;
}

.section-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  text-align: center;
  max-width: 560px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

/* Highlights */
.highlights {
  padding: 64px 0;
}

.highlights .section-title {
  margin-bottom: 40px;
}

.highlights-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 32px;
}

.highlight-card {
  background: var(--surface);
  padding: 32px 24px;
  border-radius: 12px;
  border: 1px solid var(--border);
  text-align: center;
}

.highlight-icon {
  display: flex;
  justify-content: center;
  margin-bottom: 16px;
  color: var(--accent);
}

.highlight-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

.highlight-desc {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Section / Feature detail */
.section {
  padding: 48px 0;
}

.section-alt {
  background: var(--section-alt-bg);
  border-top: 1px solid var(--border);
}

.feature-detail {
  max-width: 640px;
  margin: 0 auto;
}

.feature-subtitle {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text);
  margin-top: 24px;
  margin-bottom: 8px;
}

.feature-detail p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.feature-detail .feature-subtitle:first-child {
  margin-top: 0;
}

/* FAQ */
.faq-section {
  padding: 48px 0 64px;
}

.faq-list {
  max-width: 640px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: 8px;
  margin-bottom: 12px;
  background: var(--surface);
  overflow: hidden;
}

.faq-item:last-child {
  margin-bottom: 0;
}

.faq-question {
  padding: 16px 20px;
  font-size: 1rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

.faq-question::after {
  content: "";
  width: 20px;
  height: 20px;
  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%234A4A4A' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E") center/contain no-repeat;
  flex-shrink: 0;
  margin-left: 8px;
}

details[open] .faq-question::after {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 20px 16px;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.faq-answer p {
  margin: 0;
}

/* Contact */
.contact-section {
  padding: 48px 0;
  background: var(--section-alt-bg);
  border-top: 1px solid var(--border);
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  justify-content: center;
  max-width: 480px;
  margin: 0 auto;
}

.contact-item {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 0.9375rem;
}

.contact-item:hover {
  border-color: var(--accent);
  color: var(--accent);
  text-decoration: none;
}

.contact-icon {
  display: flex;
  color: var(--accent);
}

/* Links */
.links-section {
  padding: 32px 0;
}

.links-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  justify-content: center;
}

.links-list a {
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

.links-list a:hover {
  color: var(--accent);
}

/* Download CTA */
.download-section {
  padding: 48px 24px;
  text-align: center;
  background: var(--accent);
  color: var(--accent-text);
}

.download-section .btn-primary {
  background: var(--surface);
  color: var(--accent);
}

.download-section .btn-primary:hover {
  background: var(--bg);
  text-decoration: none;
}

.download-text {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.download-sub {
  font-size: 0.9375rem;
  opacity: 0.9;
  margin-bottom: 24px;
}

/* Footer */
.footer {
  padding: 48px 24px 32px;
  background: var(--surface);
  border-top: 1px solid var(--border);
}

.footer-inner {
  text-align: center;
}

.footer-brand {
  margin-bottom: 24px;
}

.footer-brand .brand-text {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text);
  display: block;
  margin-bottom: 8px;
}

.footer-tagline {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 400px;
  margin: 0 auto;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 24px;
  justify-content: center;
  margin-bottom: 24px;
}

.footer-links a {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.footer-links a:hover {
  color: var(--accent);
}

.footer-download {
  margin-bottom: 24px;
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

/* Privacy page */
.privacy-main {
  padding: 48px 0 64px;
  background: var(--surface);
}

.privacy-title {
  font-size: 1.75rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

.privacy-updated {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

.privacy-section {
  margin-bottom: 32px;
}

.privacy-section h2 {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 12px;
}

.privacy-section p,
.privacy-section li {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 8px;
}

.privacy-section ul {
  margin: 8px 0 0 20px;
  padding: 0;
}

.privacy-section li {
  margin-bottom: 6px;
}

.privacy-contact {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

/* Responsive */
@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    align-items: stretch;
    text-align: center;
  }

  .nav {
    justify-content: center;
  }

  .hero-title {
    font-size: 1.5rem;
  }

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

  .contact-links {
    flex-direction: column;
  }
}