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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", "Noto Sans JP", Roboto, Helvetica, Arial, sans-serif;
  color: #111;
  background: #fff;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: #111;
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: opacity 0.15s;
}

a:hover {
  opacity: 0.5;
}

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

/* Nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #fff;
  border-bottom: 1px solid #e5e5e5;
  padding: 0 24px;
}

.nav-inner {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  height: 56px;
  gap: 24px;
}

.nav-logo {
  font-weight: 700;
  font-size: 0.9rem;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: #111;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: 20px;
  margin-left: auto;
}

.nav-links a {
  font-size: 0.85rem;
  text-decoration: none;
  color: #666;
  transition: color 0.15s;
}

.nav-links a:hover,
.nav-links a.active {
  color: #111;
}

.lang-switch {
  display: flex;
  gap: 2px;
  margin-left: 16px;
  font-size: 0.8rem;
}

.lang-btn {
  background: none;
  border: 1px solid transparent;
  padding: 2px 8px;
  cursor: pointer;
  color: #999;
  font-size: 0.8rem;
  border-radius: 3px;
  transition: all 0.15s;
  font-family: inherit;
}

.lang-btn:hover {
  color: #111;
  border-color: #e5e5e5;
}

.lang-btn.active {
  color: #111;
  border-color: #111;
  font-weight: 600;
}

/* Container */
.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Hero */
.hero {
  padding: 80px 0 60px;
}

.hero h1 {
  font-size: 2.8rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 16px;
}

.hero .tagline {
  font-size: 1.15rem;
  color: #666;
  max-width: 600px;
  line-height: 1.5;
}

/* Section */
.section {
  padding: 48px 0;
  border-top: 1px solid #e5e5e5;
}

.section:first-of-type {
  border-top: none;
}

.section-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.section-sub {
  font-size: 0.95rem;
  color: #666;
  margin-bottom: 24px;
}

/* Features */
.features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px 32px;
  list-style: none;
}

.features li {
  padding: 3px 0;
  font-size: 0.92rem;
  position: relative;
  padding-left: 18px;
}

.features li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 8px;
  height: 8px;
  background: #111;
  border-radius: 50%;
}

/* Screenshot placeholder */
.screenshot-img {
  width: 100%;
  display: block;
  margin: 24px 0;
  border: 1px solid #e5e5e5;
}

/* Code block */
.code-block {
  background: #f8f8f8;
  border: 1px solid #e5e5e5;
  padding: 16px 20px;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 0.85rem;
  line-height: 1.7;
  border-radius: 4px;
  overflow-x: auto;
  margin: 12px 0;
}

.code-block .comment {
  color: #999;
}

/* Blockquote / info box */
.info-box {
  background: #f8f8f8;
  border-left: 3px solid #111;
  padding: 16px 20px;
  margin: 16px 0;
  font-size: 0.9rem;
  color: #444;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 10px 24px;
  background: #111;
  color: #fff !important;
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: opacity 0.15s;
  border-radius: 4px;
}

.btn:hover {
  opacity: 0.8;
}

.btn-outline {
  background: transparent;
  color: #111 !important;
  border: 1px solid #111;
}

.btn-outline:hover {
  background: #111;
  color: #fff !important;
  opacity: 1;
}

/* Release entry */
.release {
  padding: 32px 0;
  border-bottom: 1px solid #e5e5e5;
}

.release:last-child {
  border-bottom: none;
}

.release-header {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.release-version {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.release-date {
  font-size: 0.85rem;
  color: #999;
}

.release-tag {
  font-size: 0.75rem;
  background: #f0f0f0;
  padding: 2px 8px;
  border-radius: 3px;
  color: #666;
}

.release-notes {
  font-size: 0.92rem;
  color: #444;
  line-height: 1.7;
}

.release-notes ul {
  list-style: none;
  padding: 0;
  margin: 8px 0;
}

.release-notes li {
  padding: 2px 0 2px 16px;
  position: relative;
}

.release-notes li::before {
  content: "-";
  position: absolute;
  left: 0;
  color: #999;
}

/* Footer */
.footer {
  border-top: 1px solid #e5e5e5;
  padding: 40px 0;
  margin-top: 48px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  font-size: 0.85rem;
}

.footer-links a {
  color: #666;
  text-decoration: none;
}

.footer-links a:hover {
  color: #111;
}

.footer-copy {
  margin-top: 16px;
  font-size: 0.8rem;
  color: #999;
}

/* Section anchor */
.section-anchor {
  scroll-margin-top: 72px;
}

/* Responsive */
@media (max-width: 640px) {
  .nav {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .hero h1 {
    font-size: 2rem;
  }

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

  .nav-inner {
    gap: 12px;
  }

  .lang-switch {
    margin-left: 8px;
  }

  .nav-links {
    gap: 12px;
  }

  .cta-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
    align-items: center;
  }

  .cta-group .btn {
    width: 100%;
    max-width: 320px;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.6rem;
  }

  .lang-switch {
    gap: 1px;
  }

  .lang-btn {
    padding: 2px 5px;
    font-size: 0.75rem;
  }

  .nav-links {
    gap: 8px;
  }

  .nav-links a {
    font-size: 0.8rem;
  }

  .nav-inner {
    gap: 8px;
  }
}