/* ==========================================================================
   common/css/base.css
   共通デザインシステム（コンポーネント・レイアウト）
   各サイトは reset.css → tokens.css → base.css → style.css の順で読み込む。
   tokens.css で下記のCSSカスタムプロパティを必ず定義すること。

   必須トークン一覧（各サイトの css/tokens.css を参照）:
   --color-bg, --color-bg-alt, --color-surface, --color-text, --color-text-muted,
   --color-primary, --color-primary-dark, --color-accent, --color-accent-contrast,
   --color-border, --color-focus,
   --font-heading, --font-body,
   --radius-sm, --radius-md, --radius-lg,
   --shadow-sm, --shadow-md,
   --container-width (省略時 1120px)
   ========================================================================== */

html {
  font-size: 100%;
}

body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 1rem;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  line-height: 1.35;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--color-text);
}

p {
  color: var(--color-text);
}

a {
  transition: color 0.2s ease, opacity 0.2s ease;
}

/* ---------- レイアウト ---------- */

.container {
  width: 100%;
  max-width: var(--container-width, 1120px);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 2rem);
}

.section {
  padding-block: clamp(3.5rem, 8vw, 6.5rem);
}

.section--alt {
  background: var(--color-bg-alt);
}

.section--compact {
  padding-block: clamp(2.5rem, 5vw, 4rem);
}

.section-head {
  max-width: 640px;
  margin-bottom: clamp(2rem, 5vw, 3.25rem);
}

.section-head--center {
  margin-inline: auto;
  text-align: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: 0.9em;
}

.eyebrow::before {
  content: "";
  width: 1.75em;
  height: 2px;
  background: var(--color-accent);
  display: inline-block;
}

.section-title {
  font-size: clamp(1.6rem, 3.2vw, 2.35rem);
  margin-bottom: 0.75em;
}

.section-lead {
  color: var(--color-text-muted);
  font-size: 1.0625rem;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  background: var(--color-primary);
  color: #fff;
  padding: 0.75em 1.25em;
  border-radius: var(--radius-sm);
  z-index: 200;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 1rem;
}

/* ---------- グリッド ---------- */

.grid {
  display: grid;
  gap: clamp(1.25rem, 3vw, 2rem);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 880px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 600px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* ---------- ヘッダー / ナビ ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--color-bg) 88%, transparent);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
}

.site-header.is-scrolled {
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.site-header__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding-block: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6em;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--color-text);
}

.brand__mark {
  width: 2.1em;
  height: 2.1em;
  border-radius: var(--radius-sm);
  background: var(--color-primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 0.85rem;
  flex-shrink: 0;
}

.nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.5vw, 2.25rem);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: clamp(0.9rem, 2vw, 1.75rem);
  font-size: 0.9375rem;
  font-weight: 600;
}

.nav-list a {
  color: var(--color-text-muted);
  padding-block: 0.25rem;
  border-bottom: 2px solid transparent;
}

.nav-list a:hover,
.nav-list a:focus-visible,
.nav-list a[aria-current="page"] {
  color: var(--color-text);
  border-bottom-color: var(--color-accent);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--color-text);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

@media (max-width: 860px) {
  .nav-toggle { display: inline-flex; }

  .nav {
    position: fixed;
    inset: 0 0 auto auto;
    top: 0;
    height: 100svh;
    width: min(78vw, 320px);
    background: var(--color-bg);
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    padding: 5.5rem 1.75rem 2rem;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    box-shadow: var(--shadow-md);
  }

  .nav.is-open { transform: translateX(0); }

  .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 1.1rem;
    font-size: 1.05rem;
  }

  .nav .btn { width: 100%; text-align: center; }
}

.nav-scrim {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(15, 20, 30, 0.4);
  z-index: 90;
}

.nav-scrim.is-open { display: block; }

/* ---------- ボタン ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5em;
  font-weight: 700;
  font-size: 0.9375rem;
  padding: 0.85em 1.6em;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  line-height: 1.2;
  white-space: nowrap;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-on-primary, #fff);
  box-shadow: var(--shadow-sm);
}

.btn--primary:hover, .btn--primary:focus-visible {
  background: var(--color-primary-dark);
}

.btn--outline {
  border-color: var(--color-border);
  color: var(--color-text);
}

.btn--outline:hover, .btn--outline:focus-visible {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn--accent {
  background: var(--color-accent);
  color: var(--color-accent-contrast, #fff);
}

.btn--accent:hover, .btn--accent:focus-visible {
  filter: brightness(0.92);
}

.btn--block { width: 100%; }
.btn--sm { padding: 0.6em 1.15em; font-size: 0.85rem; }

/* ---------- カード ---------- */

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: clamp(1.5rem, 3vw, 2rem);
}

.card--flat {
  border: none;
  box-shadow: var(--shadow-sm);
}

.card__icon {
  width: 3rem;
  height: 3rem;
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--color-primary) 12%, transparent);
  color: var(--color-primary);
  display: grid;
  place-items: center;
  margin-bottom: 1.25rem;
}

.card__title {
  font-size: 1.1rem;
  margin-bottom: 0.6em;
}

.card__text {
  color: var(--color-text-muted);
  font-size: 0.9375rem;
}

/* ---------- バッジ / タグ ---------- */

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.35em 0.85em;
  border-radius: 999px;
  background: color-mix(in srgb, var(--color-accent) 16%, transparent);
  color: var(--color-primary-dark);
}

/* ---------- 料金テーブル ---------- */

.price-card {
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: clamp(1.75rem, 3vw, 2.25rem);
  height: 100%;
}

.price-card--featured {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
  position: relative;
}

.price-card__name {
  font-size: 1.0625rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.price-card__range {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 2.6vw, 1.9rem);
  font-weight: 800;
  color: var(--color-primary-dark);
  margin-bottom: 0.25rem;
}

.price-card__note {
  color: var(--color-text-muted);
  font-size: 0.8125rem;
  margin-bottom: 1.5rem;
}

.price-card__list {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  font-size: 0.9375rem;
  margin-bottom: 1.75rem;
  flex-grow: 1;
}

.price-card__list li {
  display: flex;
  gap: 0.6em;
  align-items: flex-start;
}

/* ---------- FAQ（アコーディオン） ---------- */

.faq-item {
  border-bottom: 1px solid var(--color-border);
}

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem 0;
  font-weight: 700;
  list-style: none;
  cursor: pointer;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--color-primary);
  flex-shrink: 0;
  transition: transform 0.2s ease;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
}

.faq-item__body {
  padding-bottom: 1.4rem;
  color: var(--color-text-muted);
  font-size: 0.9375rem;
}

/* ---------- ステップ / フロー ---------- */

.steps {
  counter-reset: step;
  display: grid;
  gap: 1.25rem;
}

.step {
  counter-increment: step;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.1rem;
  padding: 1.4rem 0;
  border-bottom: 1px solid var(--color-border);
}

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

.step::before {
  content: counter(step, decimal-leading-zero);
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--color-primary);
  width: 2.6rem;
  height: 2.6rem;
  border-radius: 50%;
  border: 2px solid var(--color-primary);
  display: grid;
  place-items: center;
  flex-shrink: 0;
}

.step__title { font-size: 1.05rem; margin-bottom: 0.35rem; }
.step__text { color: var(--color-text-muted); font-size: 0.9375rem; }

/* ---------- フォーム ---------- */

.form-grid {
  display: grid;
  gap: 1.25rem;
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.form-field label {
  font-size: 0.875rem;
  font-weight: 700;
}

.form-field .req {
  color: var(--color-accent);
  font-weight: 700;
  margin-left: 0.25em;
  font-size: 0.75rem;
}

.form-field input,
.form-field select,
.form-field textarea {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.8em 1em;
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.9375rem;
}

.form-field input:focus-visible,
.form-field select:focus-visible,
.form-field textarea:focus-visible {
  border-color: var(--color-primary);
}

.form-field textarea { resize: vertical; min-height: 8rem; }

.form-note {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

.form-status {
  border-radius: var(--radius-sm);
  padding: 1em 1.25em;
  font-size: 0.9375rem;
  font-weight: 600;
}

.form-status[data-state="loading"] {
  background: color-mix(in srgb, currentColor 8%, transparent);
  color: var(--color-text-muted);
}

.form-status[data-state="success"] {
  background: color-mix(in srgb, #2e8b57 14%, transparent);
  color: #1f6b41;
}

.form-status[data-state="error"] {
  background: color-mix(in srgb, #c0392b 14%, transparent);
  color: #a5301f;
}

.form-status[hidden] { display: none; }

/* ---------- フッター ---------- */

.site-footer {
  background: var(--color-footer-bg, var(--color-text));
  color: var(--color-footer-text, #fff);
  padding-block: clamp(3rem, 6vw, 4.5rem) 2rem;
}

.site-footer a { opacity: 0.85; }
.site-footer a:hover, .site-footer a:focus-visible { opacity: 1; }

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2.5rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(255,255,255,0.15);
}

@media (max-width: 700px) {
  .footer-grid { grid-template-columns: 1fr; }
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.5rem;
  font-size: 0.8125rem;
  opacity: 0.75;
}

/* ---------- パンくず / 戻る導線 ---------- */

.back-bar {
  background: var(--color-bg-alt);
  border-bottom: 1px solid var(--color-border);
  font-size: 0.875rem;
}

.back-bar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 0.85rem;
}

.back-bar a {
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  font-weight: 700;
  color: var(--color-primary);
}

.demo-flag {
  color: var(--color-text-muted);
}

/* ---------- スクロールフェードイン ----------
   重要: .reveal要素は既定で「表示状態」。JS実行後に付与される
   <html class="js-reveal"> の場合のみ非表示スタートにする（プログレッシブ
   エンハンスメント）。こうすることで、JS未実行・IntersectionObserver未対応・
   クローラーによる非スクロール取得などでもコンテンツが常に見える状態を保証する。
   ========================================================================== */

.reveal {
  opacity: 1;
  transform: none;
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.js-reveal .reveal {
  opacity: 0;
  transform: translateY(16px);
}

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

@media (prefers-reduced-motion: reduce) {
  .reveal, .js-reveal .reveal { opacity: 1; transform: none; transition: none; }
}

/* ---------- ユーティリティ ---------- */

.mt-0 { margin-top: 0; }
.text-center { text-align: center; }
.text-muted { color: var(--color-text-muted); }
.flow-sm > * + * { margin-top: 0.75rem; }
.flow > * + * { margin-top: 1.25rem; }

hr.divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin-block: 2rem;
}