:root {
  --primary: #1e3a6e;
  --primary-pressed: #152a52;
  --primary-soft: #e8eef6;
  --accent: #e04a35;
  --bg: #f7f4ef;
  --bg-deep: #efe8df;
  --surface: #ffffff;
  --text: #1a1f2e;
  --muted: #6b7280;
  --border: #e6e1da;
  --success: #2f7d4a;
  --font-display: "ZCOOL XiaoWei", "Songti SC", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --shadow: 0 18px 48px rgba(30, 58, 110, 0.1);
  --radius: 20px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img {
  display: block;
  max-width: 100%;
}

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

.skip {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--primary);
  color: #fff;
  padding: 0.5rem 1rem;
  z-index: 100;
}

.skip:focus {
  left: 1rem;
  top: 1rem;
}

/* ——— Top ——— */
.top {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem clamp(1.1rem, 4vw, 2.5rem);
  background: rgba(247, 244, 239, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(230, 225, 218, 0.8);
}

.top__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 0.02em;
}

.top__logo {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  object-fit: cover;
  box-shadow: 0 4px 12px rgba(30, 58, 110, 0.15);
}

.top__nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.35rem 1.15rem;
  font-size: 0.92rem;
  color: var(--muted);
}

.top__nav a {
  transition: color 0.2s var(--ease);
}

.top__nav a:hover {
  color: var(--primary);
}

/* ——— Hero ——— */
.hero {
  position: relative;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: center;
  min-height: calc(100svh - 64px);
  padding: clamp(2.5rem, 7vh, 4.5rem) clamp(1.1rem, 4vw, 2.5rem)
    clamp(3rem, 8vh, 5rem);
  overflow: hidden;
}

.hero__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  background:
    radial-gradient(ellipse 70% 55% at 12% 18%, rgba(30, 58, 110, 0.14), transparent 58%),
    radial-gradient(ellipse 55% 45% at 88% 22%, rgba(224, 74, 53, 0.1), transparent 55%),
    linear-gradient(165deg, #f7f4ef 0%, #efe8df 48%, #f7f4ef 100%);
}

.hero__glow {
  position: absolute;
  width: 42vw;
  height: 42vw;
  right: -8%;
  top: 8%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(232, 238, 246, 0.95), transparent 68%);
  z-index: 0;
  pointer-events: none;
}

.hero__inner,
.hero__card {
  position: relative;
  z-index: 1;
}

.hero__mascot {
  width: 88px;
  height: 88px;
  border-radius: 22px;
  margin-bottom: 1.1rem;
  box-shadow: var(--shadow);
  animation: float-in 0.9s var(--ease) both;
}

.hero__name {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 7vw, 4.2rem);
  line-height: 1.05;
  color: var(--primary);
  letter-spacing: 0.02em;
  animation: float-in 0.9s var(--ease) 0.08s both;
}

.hero__slogan {
  margin: 0.85rem 0 0;
  font-size: clamp(1.15rem, 2.4vw, 1.45rem);
  font-weight: 600;
  color: var(--accent);
  animation: float-in 0.9s var(--ease) 0.16s both;
}

.hero__lead {
  margin: 1rem 0 0;
  max-width: 28rem;
  color: var(--muted);
  font-size: 1.05rem;
  animation: float-in 0.9s var(--ease) 0.24s both;
}

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.75rem;
  animation: float-in 0.9s var(--ease) 0.32s both;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.75rem 1.35rem;
  border-radius: 14px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: transform 0.25s var(--ease), background 0.25s var(--ease),
    box-shadow 0.25s var(--ease);
}

.btn:hover {
  transform: translateY(-2px);
}

.btn--primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 10px 24px rgba(30, 58, 110, 0.22);
}

.btn--primary:hover {
  background: var(--primary-pressed);
}

.btn--ghost {
  background: transparent;
  color: var(--primary);
  border: 1.5px solid rgba(30, 58, 110, 0.28);
}

.btn--ghost:hover {
  background: var(--primary-soft);
}

.hero__card {
  display: flex;
  justify-content: center;
  animation: float-in 1s var(--ease) 0.2s both;
}

.flash {
  width: min(100%, 320px);
  aspect-ratio: 3 / 4;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 28px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem 1.5rem;
  text-align: center;
  transform: rotate(2.5deg);
  transition: transform 0.45s var(--ease);
}

.flash:hover {
  transform: rotate(0deg) translateY(-6px);
}

.flash__kana {
  margin: 0;
  font-size: clamp(2rem, 5vw, 2.6rem);
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 0.04em;
}

.flash__rule {
  width: 64%;
  margin: 1.1rem 0 0.9rem;
  border-top: 2px dotted rgba(107, 114, 128, 0.45);
}

.flash__read {
  margin: 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.flash__hint {
  margin: 1.4rem 0 0;
  font-size: 0.82rem;
  color: rgba(107, 114, 128, 0.85);
}

/* ——— Sections ——— */
.section__head {
  text-align: center;
  max-width: 36rem;
  margin: 0 auto 2.5rem;
}

.section__head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.5vw, 2.25rem);
  color: var(--primary);
}

.section__head p {
  margin: 0.65rem 0 0;
  color: var(--muted);
}

.how {
  padding: clamp(3.5rem, 9vw, 5.5rem) clamp(1.1rem, 4vw, 2.5rem);
  background: linear-gradient(180deg, transparent, rgba(232, 238, 246, 0.45));
}

.steps {
  list-style: none;
  margin: 0 auto;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
  max-width: 1080px;
}

.step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem 1.35rem 1.6rem;
  box-shadow: 0 8px 24px rgba(30, 58, 110, 0.04);
}

.step__n {
  display: inline-block;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.06em;
  font-size: 0.9rem;
  margin-bottom: 0.7rem;
}

.step h3 {
  margin: 0 0 0.45rem;
  font-size: 1.15rem;
  color: var(--text);
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.features {
  padding: clamp(3.5rem, 9vw, 5.5rem) clamp(1.1rem, 4vw, 2.5rem);
}

.grid {
  max-width: 1080px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.15rem;
}

.feat {
  padding: 1.45rem 1.4rem;
  border-radius: var(--radius);
  background: var(--surface);
  border: 1px solid var(--border);
}

.feat h3 {
  margin: 0 0 0.4rem;
  color: var(--primary);
  font-size: 1.1rem;
}

.feat p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.platforms {
  padding: 0 clamp(1.1rem, 4vw, 2.5rem) clamp(4rem, 10vw, 6rem);
}

.platforms__inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: clamp(1.8rem, 4vw, 2.4rem);
  border-radius: 28px;
  background:
    linear-gradient(135deg, rgba(30, 58, 110, 0.96), rgba(21, 42, 82, 0.98));
  color: #f7f4ef;
  box-shadow: var(--shadow);
}

.platforms__inner h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 1.9rem);
}

.platforms__inner > p {
  margin: 0.55rem 0 1.4rem;
  opacity: 0.88;
}

.platforms__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}

.platforms__list li {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1rem;
  align-items: baseline;
  padding: 0.85rem 1rem;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.platforms__list strong {
  color: #fff;
  min-width: 6.5rem;
}

.platforms__list span {
  opacity: 0.86;
  font-size: 0.95rem;
}

/* ——— Footer ——— */
.foot {
  border-top: 1px solid var(--border);
  padding: 2rem clamp(1.1rem, 4vw, 2.5rem) 2.5rem;
  display: grid;
  gap: 1.1rem;
  background: #fff9f2;
}

.foot__brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.foot__brand img {
  width: 36px;
  height: 36px;
  border-radius: 10px;
}

.foot__brand strong {
  display: block;
  color: var(--primary);
}

.foot__brand span {
  display: block;
  font-size: 0.85rem;
  color: var(--muted);
}

.foot__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem 1.25rem;
  color: var(--primary);
  font-weight: 500;
  font-size: 0.95rem;
}

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

.foot__copy {
  margin: 0;
  color: var(--muted);
  font-size: 0.85rem;
}

/* ——— Motion ——— */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes float-in {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal,
  .hero__mascot,
  .hero__name,
  .hero__slogan,
  .hero__lead,
  .hero__cta,
  .hero__card,
  .flash {
    animation: none !important;
    transition: none !important;
    opacity: 1 !important;
    transform: none !important;
  }
}

@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero__card {
    order: -1;
  }

  .flash {
    width: min(100%, 260px);
    aspect-ratio: 4 / 5;
    transform: rotate(0);
  }

  .steps,
  .grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .top__nav {
    display: none;
  }
}