:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --bg-soft: #eef4fb;
  --surface: rgba(255, 255, 255, .84);
  --surface-solid: #ffffff;
  --surface-2: #eef4fb;
  --text: #111827;
  --muted: #667085;
  --subtle: #98a2b3;
  --line: rgba(17, 24, 39, .10);
  --line-strong: rgba(17, 24, 39, .16);
  --blue: #1f66b3;
  --blue-2: #e6f1fb;
  --blue-3: #d8eaff;
  --shadow: 0 24px 70px rgba(31, 50, 84, .14);
  --soft-shadow: 0 18px 54px rgba(31, 50, 84, .08);
  --radius: 28px;
  --container: 1120px;
  --header-bg: rgba(245, 247, 251, .82);
  --hero-glow: rgba(31, 102, 179, .20);
  --final-start: #111827;
  --final-end: #1f66b3;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #090d16;
  --bg-soft: #111827;
  --surface: rgba(17, 24, 39, .78);
  --surface-solid: #111827;
  --surface-2: #172033;
  --text: #f8fafc;
  --muted: #a7b0c0;
  --subtle: #778296;
  --line: rgba(226, 232, 240, .12);
  --line-strong: rgba(226, 232, 240, .22);
  --blue: #75b7ff;
  --blue-2: rgba(117, 183, 255, .14);
  --blue-3: rgba(117, 183, 255, .22);
  --shadow: 0 28px 90px rgba(0, 0, 0, .42);
  --soft-shadow: 0 18px 54px rgba(0, 0, 0, .30);
  --header-bg: rgba(9, 13, 22, .78);
  --hero-glow: rgba(96, 165, 250, .24);
  --final-start: #101827;
  --final-end: #123c70;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 15% 0%, color-mix(in srgb, var(--blue) 14%, transparent), transparent 32%),
    radial-gradient(circle at 92% 6%, color-mix(in srgb, var(--blue) 13%, transparent), transparent 28%),
    var(--bg);
  line-height: 1.75;
  letter-spacing: .01em;
  transition: background-color .22s ease, color .22s ease;
}

body.mobile-menu-open {
  overflow: hidden;
}

a {
  color: inherit;
}

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

.container {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  background: var(--header-bg);
  border-bottom: 1px solid var(--line);
}

.nav {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  text-decoration: none;
  font-weight: 900;
  letter-spacing: .02em;
}

.brand-mark {
  width: 38px;
  height: 38px;
  border-radius: 13px;
  display: grid;
  place-items: center;
  color: #fff;
  background: linear-gradient(135deg, #1f66b3, #7aa7df);
  box-shadow: 0 12px 24px rgba(31, 102, 179, .28);
  font-size: 20px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 800;
}

.nav-links a,
.footer-links a,
.mobile-menu a {
  text-decoration: none;
}

.nav-links a:hover,
.footer-links a:hover,
.mobile-menu a:hover {
  color: var(--blue);
}

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

.btn,
.btn-secondary,
.btn-text,
.theme-toggle,
.mobile-menu-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 999px;
  border: 0;
  text-decoration: none;
  font: inherit;
  font-weight: 850;
  font-size: 14px;
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease, border-color .18s ease, color .18s ease;
  white-space: nowrap;
}

.btn {
  color: #fff;
  background: #111827;
  box-shadow: 0 16px 34px rgba(17, 24, 39, .18);
}

:root[data-theme="dark"] .btn {
  color: #07111f;
  background: #f8fafc;
  box-shadow: 0 18px 40px rgba(248, 250, 252, .10);
}

.btn:hover,
.btn-secondary:hover,
.btn-text:hover,
.theme-toggle:hover,
.mobile-menu-button:hover {
  transform: translateY(-1px);
}

.btn-secondary {
  color: var(--blue);
  background: var(--blue-2);
  border: 1px solid color-mix(in srgb, var(--blue) 18%, transparent);
}

.btn-text,
.theme-toggle,
.mobile-menu-button {
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--line);
}

.theme-toggle {
  padding: 0 14px;
  min-width: 94px;
}

.theme-toggle-icon {
  width: 18px;
  text-align: center;
}

.mobile-menu-button {
  display: none;
  min-width: 48px;
  padding: 0;
  font-size: 22px;
}

.mobile-menu {
  border-top: 1px solid var(--line);
  background: var(--header-bg);
}

.mobile-menu-inner {
  display: grid;
  gap: 4px;
  padding: 12px 0 18px;
}

.mobile-menu a {
  border-radius: 14px;
  padding: 12px 14px;
  color: var(--muted);
  font-weight: 800;
}

.hero {
  padding: 86px 0 74px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(380px, .9fr);
  gap: 64px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--blue);
  background: var(--blue-2);
  border: 1px solid color-mix(in srgb, var(--blue) 18%, transparent);
  border-radius: 999px;
  padding: 8px 13px;
  font-size: 13px;
  font-weight: 850;
  margin-bottom: 22px;
}

.eyebrow::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--blue) 14%, transparent);
}

h1,
h2,
h3,
p,
figure {
  margin: 0;
}

h1 {
  font-size: clamp(42px, 6vw, 72px);
  line-height: 1.08;
  letter-spacing: -.045em;
  font-weight: 900;
}

h2 {
  font-size: clamp(30px, 4vw, 48px);
  line-height: 1.2;
  letter-spacing: -.035em;
  font-weight: 900;
}

h3 {
  font-size: 20px;
  line-height: 1.45;
  font-weight: 900;
}

.hero-copy {
  margin-top: 24px;
  max-width: 680px;
  color: var(--muted);
  font-size: clamp(16px, 1.6vw, 19px);
  font-weight: 500;
}

.hero-copy strong {
  color: var(--text);
  font-weight: 850;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.store-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-width: 260px;
  min-height: 64px;
  padding: 0 30px;
  border-radius: 999px;
  font-weight: 800;
  text-decoration: none;
  line-height: 1;
  white-space: nowrap;
}

.store-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  font-size: 25px;
  line-height: 1;
  flex: 0 0 auto;
}

.android-icon svg {
  width: 24px;
  height: 24px;
  display: block;
  fill: currentColor;
}

.store-btn-ios {
  background: #f8fafc;
  color: #0f172a;
  border: 1px solid rgba(255, 255, 255, 0.7);
}

.store-btn-android {
  background: rgba(96, 165, 250, 0.16);
  color: #7cc1ff;
  border: 1px solid rgba(96, 165, 250, 0.38);
}

.store-btn:hover {
  transform: translateY(-1px);
}

@media (max-width: 640px) {
  .hero-actions {
    gap: 14px;
  }

  .store-btn {
    width: 100%;
    min-width: 0;
    min-height: 58px;
    padding: 0 22px;
  }
}

.note {
  color: var(--muted);
  font-size: 13px;
  margin-top: 14px;
}

.hero-points {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 38px;
  max-width: 690px;
}

.point,
.card,
.screen-card,
.flow-item,
.article-card,
details,
.school-search {
  border: 1px solid var(--line);
  background: var(--surface);
  box-shadow: var(--soft-shadow);
}

.point {
  padding: 17px;
  border-radius: 20px;
}

.point strong,
.point span {
  display: block;
}

.point strong {
  font-size: 15px;
  line-height: 1.45;
}

.point span {
  margin-top: 5px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.55;
}

.device-stage {
  position: relative;
  min-height: 640px;
}

.device-glow {
  position: absolute;
  inset: 12% -5% auto auto;
  width: 78%;
  height: 58%;
  border-radius: 999px;
  background: radial-gradient(circle, var(--hero-glow), transparent 65%);
  filter: blur(18px);
  z-index: 0;
}

.phone-shot {
  position: absolute;
  width: 52%;
  min-width: 218px;
  border-radius: 34px;
  overflow: hidden;
  background: #f5f7fb;
  border: 1px solid rgba(17, 24, 39, .08);
  box-shadow: var(--shadow);
}

:root[data-theme="dark"] .phone-shot {
  border-color: rgba(226, 232, 240, .18);
  box-shadow: 0 30px 90px rgba(0, 0, 0, .58), 0 0 0 1px rgba(255, 255, 255, .04) inset;
}

.phone-shot img {
  width: 100%;
  height: auto;
}

.phone-shot.main {
  right: 8%;
  top: 0;
  width: 58%;
  z-index: 3;
  transform: rotate(.8deg);
}

.phone-shot.sub-a {
  left: 0;
  top: 104px;
  width: 43%;
  z-index: 2;
  transform: rotate(-5deg);
  opacity: .98;
}

.phone-shot.sub-b {
  left: 64px;
  bottom: 22px;
  width: 42%;
  z-index: 1;
  transform: rotate(4deg);
  opacity: .96;
}

.floating-label {
  position: absolute;
  right: 0;
  bottom: 98px;
  z-index: 4;
  width: 238px;
  padding: 16px 17px;
  border: 1px solid color-mix(in srgb, var(--blue) 18%, transparent);
  background: color-mix(in srgb, var(--surface-solid) 88%, transparent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-radius: 22px;
  box-shadow: var(--soft-shadow);
}

.floating-label strong,
.floating-label span {
  display: block;
}

.floating-label strong {
  font-size: 15px;
  line-height: 1.45;
}

.floating-label span {
  color: var(--muted);
  font-size: 12px;
  line-height: 1.65;
}

section {
  padding: 78px 0;
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 30px;
}

.section-kicker {
  color: var(--blue);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: .08em;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.section-lead {
  margin-top: 12px;
  color: var(--muted);
  max-width: 720px;
  font-size: 16px;
}

.cards-3,
.screen-grid,
.flow,
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.card,
.flow-item {
  border-radius: var(--radius);
  padding: 26px;
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: 16px;
  background: var(--blue-2);
  color: var(--blue);
  display: grid;
  place-items: center;
  font-size: 23px;
  margin-bottom: 18px;
}

.card p,
.flow-item p,
details p {
  margin-top: 10px;
  color: var(--muted);
  font-size: 14px;
}

.screen-grid {
  gap: 20px;
  align-items: start;
}

.screen-card {
  border-radius: 30px;
  padding: 14px;
  box-shadow: var(--shadow);
}

.screen-card img {
  border-radius: 23px;
  border: 1px solid rgba(17, 24, 39, .08);
  width: 100%;
  background: #f2f4f7;
}

:root[data-theme="dark"] .screen-card img {
  border-color: rgba(226, 232, 240, .16);
}

.screen-card figcaption {
  padding: 17px 8px 5px;
}

.screen-card strong,
.screen-card span {
  display: block;
}

.screen-card strong {
  font-size: 17px;
  line-height: 1.45;
}

.screen-card span {
  margin-top: 6px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.65;
}

.flow {
  counter-reset: step;
}

.flow-item {
  position: relative;
  min-height: 220px;
}

.flow-item::before {
  counter-increment: step;
  content: "0" counter(step);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 999px;
  background: var(--text);
  color: var(--bg);
  font-weight: 900;
  font-size: 13px;
  margin-bottom: 24px;
}

.wide-panel {
  display: grid;
  grid-template-columns: 1fr .9fr;
  gap: 34px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 34px;
  background: linear-gradient(135deg, color-mix(in srgb, var(--surface-solid) 92%, transparent), var(--blue-2));
  box-shadow: var(--shadow);
  padding: 38px;
}

.school-search {
  border-radius: 28px;
  padding: 22px;
}

.search-box {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 54px;
  border-radius: 18px;
  background: var(--surface-2);
  color: var(--muted);
  padding: 0 16px;
  font-weight: 800;
  margin: 16px 0;
  text-decoration: none;
}

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
}

.chips a {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--line);
  background: var(--surface-solid);
  border-radius: 999px;
  padding: 8px 12px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
}

.article-card {
  display: block;
  text-decoration: none;
  border-radius: var(--radius);
  padding: 24px;
  min-height: 188px;
}

.article-card:hover {
  transform: translateY(-2px);
  border-color: var(--line-strong);
}

.article-date {
  color: var(--subtle);
  font-size: 12px;
  font-weight: 700;
}

.article-title {
  margin-top: 10px;
  font-weight: 900;
  line-height: 1.5;
}

.article-summary {
  margin-top: 8px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}

.empty {
  grid-column: 1 / -1;
  color: var(--muted);
  border: 1px dashed var(--line);
  border-radius: 22px;
  padding: 22px;
  text-align: center;
  background: color-mix(in srgb, var(--surface-solid) 55%, transparent);
}

.faq-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

details {
  border-radius: 22px;
  padding: 20px 22px;
}

summary {
  cursor: pointer;
  font-weight: 900;
}

.final-cta {
  text-align: center;
  border: 1px solid color-mix(in srgb, var(--blue) 18%, transparent);
  border-radius: 38px;
  padding: 54px 28px;
  background: linear-gradient(135deg, var(--final-start), var(--final-end));
  color: #fff;
  box-shadow: var(--shadow);
}

.final-cta .section-lead {
  color: rgba(255, 255, 255, .74);
  margin-left: auto;
  margin-right: auto;
}

.final-cta .hero-actions {
  justify-content: center;
}

.final-cta .btn {
  color: #111827;
  background: #fff;
  box-shadow: none;
}

.final-cta .btn-secondary {
  color: #fff;
  background: rgba(255, 255, 255, .12);
  border-color: rgba(255, 255, 255, .22);
}

footer {
  padding: 36px 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
}

.footer-row {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

@media (max-width: 980px) {
  .nav-links {
    display: none;
  }

  .mobile-menu-button {
    display: inline-flex;
  }

  .hero {
    padding-top: 54px;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: 34px;
  }

  .device-stage {
    min-height: 590px;
    max-width: 520px;
    margin: 0 auto;
    width: 100%;
  }

  .hero-points,
  .cards-3,
  .screen-grid,
  .flow,
  .article-grid {
    grid-template-columns: 1fr;
  }

  .wide-panel {
    grid-template-columns: 1fr;
    padding: 28px;
  }

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

  .section-head {
    display: block;
  }

  .section-link {
    margin-top: 18px;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(100% - 26px, var(--container));
  }

  .site-header {
    position: static;
  }

  .nav {
    min-height: 64px;
    gap: 12px;
  }

  .brand span:last-child {
    font-size: 14px;
  }

  .brand-mark {
    width: 34px;
    height: 34px;
    border-radius: 12px;
    font-size: 18px;
  }

  .nav-school-link,
  .theme-toggle-text {
    display: none;
  }

  .theme-toggle {
    min-width: 48px;
    padding: 0;
  }

  .hero {
    padding: 36px 0 46px;
  }

  h1 {
    font-size: 42px;
  }

  .hero-copy {
    font-size: 15px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions a {
    width: 100%;
  }

  .hero-points {
    margin-top: 28px;
  }

  section {
    padding: 52px 0;
  }

  h2 {
    font-size: 31px;
  }

  .device-stage {
    min-height: 500px;
  }

  .phone-shot {
    border-radius: 26px;
  }

  .phone-shot.main {
    width: 62%;
    right: 2%;
  }

  .phone-shot.sub-a {
    width: 46%;
    left: 0;
    top: 90px;
  }

  .phone-shot.sub-b {
    width: 45%;
    left: 32px;
    bottom: 18px;
  }

  .floating-label {
    right: 0;
    bottom: 74px;
    width: 205px;
    padding: 13px 14px;
  }

  .card,
  .flow-item {
    padding: 22px;
  }

  .wide-panel {
    border-radius: 28px;
    padding: 22px;
  }

  .final-cta {
    border-radius: 28px;
    padding: 38px 20px;
  }

  .footer-row {
    display: block;
  }

  .footer-links {
    margin-top: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}