:root {
  --ink: #1e2a3a;
  --ink-soft: #546e7a;
  --paper: #f0e6da;
  --paper-2: #f6eee4;
  --aka: #c41e3a;
  --aka-deep: #9b1830;
  --line: rgba(196, 30, 58, 0.14);
  --max: 68rem;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Source Sans 3", system-ui, sans-serif;
  color: var(--ink);
  background:
    radial-gradient(ellipse 80% 50% at 10% -10%, rgba(196, 30, 58, 0.09), transparent 55%),
    radial-gradient(ellipse 60% 40% at 100% 0%, rgba(46, 64, 87, 0.08), transparent 50%),
    var(--paper);
  line-height: 1.55;
}

a {
  color: var(--aka-deep);
}

a:hover {
  color: var(--aka);
}

.wrap {
  width: min(100% - 2.5rem, var(--max));
  margin-inline: auto;
}

/* Header */

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 0;
  gap: 1rem;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-family: "Shippori Mincho", "Noto Serif JP", serif;
  font-weight: 600;
  font-size: 1.35rem;
  letter-spacing: 0.02em;
  color: var(--ink);
  text-decoration: none;
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 22%;
  display: block;
  animation: logo-soft 4s ease-in-out infinite;
}

@keyframes logo-soft {
  0%,
  100% {
    transform: scale(1);
    opacity: 1;
  }
  50% {
    transform: scale(1.04);
    opacity: 0.92;
  }
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.nav a {
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.95rem;
}

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

.lang {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin-left: 0.25rem;
  padding-left: 0.75rem;
  border-left: 1px solid var(--line);
  font-size: 0.9rem;
}

.lang a {
  color: var(--ink-soft);
  text-decoration: none;
}

.lang a[aria-current="page"] {
  color: var(--aka);
  font-weight: 600;
}

/* Hero */

.hero {
  padding: 3.5rem 0 4rem;
  display: grid;
  gap: 1.25rem;
  max-width: 38rem;
  animation: rise 0.8s ease both;
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.hero h1 {
  font-family: "Shippori Mincho", "Noto Serif JP", serif;
  font-weight: 600;
  font-size: clamp(2.4rem, 6vw, 3.6rem);
  line-height: 1.15;
  margin: 0;
  letter-spacing: -0.02em;
}

.hero .lead {
  margin: 0;
  font-size: 1.15rem;
  color: var(--ink-soft);
  max-width: 32rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.35rem;
  border-radius: 0.35rem;
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  border: 1px solid transparent;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.btn-primary {
  background: var(--aka);
  color: #fff;
}

.btn-primary:hover {
  background: var(--aka-deep);
  color: #fff;
}

.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line);
}

.btn-ghost:hover {
  border-color: var(--aka);
  color: var(--aka);
}

/* Sections */

.section {
  padding: 2.75rem 0;
  border-top: 1px solid var(--line);
}

.section h2 {
  font-family: "Shippori Mincho", serif;
  font-size: 1.75rem;
  margin: 0 0 1.25rem;
}

.features {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  list-style: none;
  padding: 0;
  margin: 0;
}

.features li {
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-radius: 0.5rem;
  padding: 1.15rem 1.2rem;
}

.features strong {
  display: block;
  margin-bottom: 0.35rem;
  font-size: 1.05rem;
}

.features span {
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.note {
  color: var(--ink-soft);
  font-size: 0.95rem;
  max-width: 36rem;
}

/* Screenshots */

.screen-row {
  display: flex;
  gap: 1rem;
  overflow-x: auto;
  padding-bottom: 0.5rem;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}

.screen-row img {
  height: min(420px, 70vh);
  width: auto;
  max-width: none;
  border-radius: 1rem;
  border: 1px solid var(--line);
  background: var(--paper-2);
  scroll-snap-align: start;
  animation: rise 0.9s ease both;
}

.screen-row img:nth-child(2) {
  animation-delay: 0.12s;
}

.screen-row img:nth-child(3) {
  animation-delay: 0.24s;
}

.screen-row img:nth-child(4) {
  animation-delay: 0.36s;
}

/* Footer */

.site-footer {
  border-top: 1px solid var(--line);
  padding: 2rem 0 3rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: space-between;
}

.site-footer a {
  text-decoration: none;
}

/* Privacy prose */

.prose {
  padding: 2rem 0 4rem;
  max-width: 42rem;
}

.prose h1 {
  font-family: "Shippori Mincho", serif;
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  margin: 0 0 0.5rem;
}

.prose .meta {
  color: var(--ink-soft);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.prose h2 {
  font-family: "Shippori Mincho", serif;
  font-size: 1.25rem;
  margin: 2rem 0 0.6rem;
}

.prose p,
.prose li {
  color: var(--ink);
}

.prose ul {
  padding-left: 1.2rem;
}

.prose code {
  font-size: 0.9em;
  background: var(--paper-2);
  padding: 0.1em 0.35em;
  border-radius: 0.25rem;
}

/* Reduced motion */

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .hero,
  .screen-row img,
  .brand img {
    animation: none;
  }
}