/* LifeBook Design System (LDS) v1.0 — Light Mode: LifeBookMaker (The Study) */
:root {
  --paper: #FDFBF7;
  --ink: #2B2B2B;
  --ink-light: #5A5A5A;
  --ink-faint: #A0A0A0;
  --brand-blue: #2C4F7C;
  --brand-blue-hover: #234060;
  --accent-amber: #D4A373;
  --card-surface: rgba(255, 255, 255, 0.72);
  --line-hair: rgba(43, 43, 43, 0.1);
  --shadow-paper: 0 4px 20px -2px rgba(43, 43, 43, 0.08);
  --shadow-soft: 0 2px 12px rgba(43, 43, 43, 0.06);
  --radius-ui: 3px;
  --main-max: 40rem;
  --gutter: clamp(1rem, 4vw, 1.5rem);
  --header-h: 3.25rem;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --font-story:
    "Hiragino Sans",
    "Hiragino Kaku Gothic ProN",
    "Yu Gothic",
    "Yu Gothic UI",
    YuGothic,
    Meiryo,
    "MS PGothic",
    sans-serif;
  --font-system: "Inter", "Noto Sans JP", system-ui, sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  min-height: 100dvh;
  font-family: var(--font-system);
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink);
  background-color: var(--paper);
}

/* 全画面背景 — 生成り・朝の光 */
.bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(ellipse 110% 75% at 10% 12%, rgba(212, 163, 115, 0.14), transparent 55%),
    radial-gradient(ellipse 95% 65% at 92% 78%, rgba(44, 79, 124, 0.08), transparent 50%),
    radial-gradient(ellipse 70% 45% at 48% 95%, rgba(253, 251, 247, 0.9), transparent 42%),
    linear-gradient(175deg, #FFFEF9 0%, var(--paper) 38%, #F7F2EA 100%);
}

a {
  color: var(--brand-blue);
  text-decoration: none;
  transition: color 0.2s var(--ease), opacity 0.2s var(--ease);
}

a:hover {
  color: var(--brand-blue-hover);
  text-decoration: underline;
  text-underline-offset: 0.2em;
}

:focus-visible {
  outline: 1px solid var(--brand-blue);
  outline-offset: 3px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-h);
  padding: 0 var(--gutter);
  padding-top: max(0.5rem, env(safe-area-inset-top));
  background: rgba(253, 251, 247, 0.88);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 0.5px solid var(--line-hair);
}

.brand {
  font-weight: 500;
  letter-spacing: 0.14em;
  font-size: 0.8125rem;
  color: var(--ink);
  text-decoration: none;
}

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

.menu-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  margin: 0;
  padding: 0;
  border: 0.5px solid var(--line-hair);
  border-radius: var(--radius-ui);
  background: rgba(255, 255, 255, 0.65);
  color: var(--ink);
  cursor: pointer;
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.menu-toggle:hover {
  border-color: rgba(44, 79, 124, 0.25);
  box-shadow: var(--shadow-soft);
}

.menu-toggle .burger {
  position: relative;
  display: block;
  width: 1.125rem;
  height: 14px;
}

.menu-toggle .burger::before,
.menu-toggle .burger::after,
.menu-toggle .burger span {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  border-radius: 0;
  transition: transform 0.2s var(--ease), opacity 0.2s var(--ease);
}

.menu-toggle .burger::before {
  top: 0;
}

.menu-toggle .burger span {
  top: 6px;
}

.menu-toggle .burger::after {
  top: 12px;
}

.menu-toggle[aria-expanded="true"] .burger::before {
  top: 6px;
  transform: rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .burger span {
  opacity: 0;
}

.menu-toggle[aria-expanded="true"] .burger::after {
  top: 6px;
  transform: rotate(-45deg);
}

.shell {
  display: block;
  padding: 1.25rem var(--gutter) 2rem;
  padding-bottom: max(2rem, env(safe-area-inset-bottom));
}

.site-nav {
  margin-bottom: 1.5rem;
}

.nav-title {
  margin: 0 0 0.75rem;
  font-family: var(--font-system);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

.nav-title + .nav-list {
  margin-bottom: 1.25rem;
}

.nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-list li + li {
  margin-top: 0.25rem;
}

.nav-link {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 0.4rem 0.65rem;
  border-radius: var(--radius-ui);
  font-family: var(--font-system);
  font-size: 0.9375rem;
  color: var(--ink);
  text-decoration: none;
  border: 0.5px solid transparent;
  background: transparent;
  transition: background 0.2s var(--ease), border-color 0.2s var(--ease);
}

.nav-link:hover {
  background: rgba(44, 79, 124, 0.06);
  border-color: rgba(44, 79, 124, 0.12);
  text-decoration: none;
}

.nav-link[aria-current="page"] {
  background: rgba(44, 79, 124, 0.08);
  border-color: rgba(44, 79, 124, 0.15);
  font-weight: 500;
}

.nav-link[aria-disabled="true"] {
  color: var(--ink-faint);
  cursor: not-allowed;
  pointer-events: none;
}

.nav-link .tag {
  margin-left: auto;
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  color: var(--ink-faint);
}

.main {
  width: 100%;
  max-width: var(--main-max);
  margin-inline: auto;
}

/* カード: 便箋メタファー — 角は浅く、影は紙の重なり（LDS paper shadow） */
.hero-card {
  padding: 2rem 1.5rem;
  border-radius: var(--radius-ui);
  background: var(--card-surface);
  border: 0.5px solid var(--line-hair);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-paper);
}

.hero-kicker {
  margin: 0 0 0.65rem;
  font-family: var(--font-system);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--brand-blue);
}

.hero-title {
  margin: 0 0 1rem;
  font-family: var(--font-story);
  font-size: clamp(1.5rem, 5vw, 1.85rem);
  font-weight: 600;
  line-height: 1.45;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.hero-lead {
  margin: 0;
  font-size: 1rem;
  line-height: 1.9;
  color: var(--ink-light);
}

.hero-line {
  height: 0.5px;
  margin: 1.5rem 0;
  background: linear-gradient(90deg, transparent, rgba(212, 163, 115, 0.45), transparent);
}

.hero-note {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--ink-faint);
}

/* 法的ページ（プライバシー・利用規約） */
.legal-card {
  padding: 2rem 1.5rem;
  border-radius: var(--radius-ui);
  background: var(--card-surface);
  border: 0.5px solid var(--line-hair);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-paper);
}

.legal-kicker {
  margin: 0 0 0.65rem;
  font-family: var(--font-system);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--brand-blue);
}

.legal-title {
  margin: 0 0 1.25rem;
  font-family: var(--font-story);
  font-size: clamp(1.35rem, 4vw, 1.65rem);
  font-weight: 600;
  line-height: 1.45;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.legal-meta {
  margin: 0 0 1.5rem;
  font-size: 0.8125rem;
  color: var(--ink-faint);
}

.legal-body h2 {
  margin: 1.75rem 0 0.65rem;
  font-family: var(--font-system);
  font-size: 1rem;
  font-weight: 500;
  color: var(--ink);
}

.legal-body h2:first-child {
  margin-top: 0;
}

.legal-body p {
  margin: 0 0 0.85rem;
  font-size: 0.9375rem;
  line-height: 1.9;
  color: var(--ink-light);
}

.legal-body ul {
  margin: 0 0 0.85rem;
  padding-left: 1.25rem;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--ink-light);
}

.legal-body li + li {
  margin-top: 0.35rem;
}

.legal-body a {
  word-break: break-all;
}

.footer-note {
  margin: 2rem auto 0;
  max-width: var(--main-max);
  text-align: center;
  font-family: var(--font-system);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--ink-faint);
}

.footer-note a {
  color: inherit;
  letter-spacing: 0.08em;
}

.footer-note a:hover {
  color: var(--brand-blue);
}

.nav-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 10;
  background: rgba(43, 43, 43, 0.18);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s var(--ease);
}

.nav-backdrop.is-open {
  opacity: 1;
  pointer-events: auto;
}

@media (max-width: 899.98px) {
  .site-header {
    display: flex;
  }

  .shell-inner {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: var(--header-h);
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 20;
    margin: 0;
    padding: 1.5rem var(--gutter);
    padding-bottom: max(1.25rem, env(safe-area-inset-bottom));
    background: rgba(253, 251, 247, 0.96);
    -webkit-backdrop-filter: blur(16px);
    backdrop-filter: blur(16px);
    border-top: 0.5px solid var(--line-hair);
    transform: translateY(-100%);
    visibility: hidden;
    transition: transform 0.3s var(--ease), visibility 0.3s;
  }

  .site-nav.is-open {
    transform: translateY(0);
    visibility: visible;
  }

  .nav-backdrop {
    display: block;
  }
}

@media (min-width: 900px) {
  .site-header {
    display: none;
  }

  .nav-backdrop {
    display: none !important;
  }

  .shell {
    display: grid;
    grid-template-columns: minmax(12rem, 1fr) minmax(0, var(--main-max)) minmax(12rem, 1fr);
    grid-template-rows: auto auto;
    gap: 0 2rem;
    align-items: start;
    min-height: calc(100dvh - 2rem);
    padding-top: 2.5rem;
    padding-left: max(var(--gutter), env(safe-area-inset-left));
    padding-right: max(var(--gutter), env(safe-area-inset-right));
  }

  .shell-inner {
    display: contents;
  }

  .site-nav {
    position: sticky;
    top: 2rem;
    grid-column: 1;
    grid-row: 1 / span 2;
    justify-self: end;
    margin: 0;
    padding: 1.5rem 0;
    width: 100%;
    max-width: 20rem;
    transform: none !important;
    visibility: visible !important;
    background: transparent;
    border: none;
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }

  .main {
    grid-column: 2;
    grid-row: 1;
    margin-inline: 0;
  }

  .footer-note {
    grid-column: 2;
    grid-row: 2;
    margin-top: 0;
    align-self: end;
  }
}