/* ── リセット & ベース ─────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --blue:       #3b82f6;
  --blue-dark:  #2563eb;
  --blue-pale:  #eff6ff;
  --slate:      #1e2a38;
  --slate-mid:  #4a5568;
  --slate-light:#718096;
  --border:     #e2e8f0;
  --bg:         #ffffff;
  --bg-soft:    #f7fafc;
  --radius:     12px;
  --shadow:     0 2px 16px rgba(0,0,0,0.07);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Hiragino Sans', 'Noto Sans JP', 'Meiryo', sans-serif;
  font-size: 15px;
  color: var(--slate);
  background: var(--bg);
  line-height: 1.7;
}

a { color: var(--blue-dark); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── ボタン ─────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 9px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.18s;
  text-decoration: none;
  border: 2px solid transparent;
}
.btn--primary {
  background: var(--slate);
  color: #fff;
}
.btn--primary:hover {
  background: #2d3748;
  text-decoration: none;
}
.btn--ghost {
  background: transparent;
  color: var(--slate);
  border-color: var(--border);
}
.btn--ghost:hover {
  background: var(--bg-soft);
  text-decoration: none;
}
.btn--lg { padding: 12px 28px; font-size: 15px; border-radius: 10px; }

/* ── ナビ ─────────────────────────────────────────── */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav__inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav__brand {
  display: flex;
  align-items: center;
  gap: 10px;
}
.nav__icon {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: var(--blue);
  color: #fff;
  font-weight: 900;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.nav__name { font-weight: 700; font-size: 15px; }

/* ── ヒーロー ─────────────────────────────────────── */
.hero {
  padding: 56px 0 48px;
  border-bottom: 1px solid var(--border);
}
.hero__inner {
  display: flex;
  align-items: flex-start;
  gap: 28px;
}
.hero__icon {
  flex-shrink: 0;
  width: 88px;
  height: 88px;
  border-radius: 20px;
  background: var(--blue);
  color: #fff;
  font-weight: 900;
  font-size: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 20px rgba(126,200,126,0.35);
}
.hero__title {
  font-size: 26px;
  font-weight: 800;
  margin-bottom: 10px;
  line-height: 1.3;
}
.hero__meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.badge {
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 700;
}
.badge--green { background: var(--blue-pale); color: var(--blue-dark); }
.badge--gray  { background: #edf2f7; color: var(--slate-mid); }
.hero__users  { font-size: 13px; color: var(--slate-light); }
.hero__desc {
  color: var(--slate-mid);
  margin-bottom: 22px;
  font-size: 15px;
  max-width: 520px;
}
.hero__actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* ── ギャラリー ───────────────────────────────────── */
.gallery {
  padding: 40px 0;
  border-bottom: 1px solid var(--border);
  background: var(--bg-soft);
}
.gallery__grid {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}
.gallery__main { flex: 1; }
.gallery__thumbs {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 140px;
  flex-shrink: 0;
}
.gallery__thumb {
  border: 2px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  background: #fff;
  cursor: pointer;
  transition: border-color 0.15s;
}
.gallery__thumb.active { border-color: var(--blue); }
.gallery__thumb:hover  { border-color: var(--blue); }
.thumb-label { font-size: 11px; color: var(--slate-mid); text-align: center; line-height: 1.4; }

/* ── モックアップ ─────────────────────────────────── */
.mockup { }
.mockup__browser {
  border: 1.5px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: var(--shadow);
  background: #fff;
}
.mockup__bar {
  background: #f1f3f5;
  padding: 8px 12px;
  display: flex;
  align-items: center;
  gap: 6px;
  border-bottom: 1px solid var(--border);
}
.mockup__dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  background: #ddd;
}
.mockup__dot:nth-child(1) { background: #fc5c57; }
.mockup__dot:nth-child(2) { background: #fdbc2c; }
.mockup__dot:nth-child(3) { background: #33c748; }
.mockup__url {
  flex: 1;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 11px;
  padding: 3px 10px;
  color: var(--slate-light);
  margin-left: 8px;
}
.mockup__content {
  display: flex;
  gap: 0;
  min-height: 280px;
}
.mockup__article {
  flex: 1;
  padding: 20px 16px;
  font-size: 12px;
  line-height: 1.8;
  color: var(--slate);
  position: relative;
}
.mockup__headline {
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 10px;
  line-height: 1.5;
}
.mockup__body {
  padding-top: 32px;
}
.mockup__word {
  position: relative;
  display: inline;
}
.mockup__highlight {
  background: #fff3cd;
  padding: 1px 2px;
  border-radius: 2px;
}
.mockup__bubble {
  display: inline-block;
  background: var(--blue);
  color: #fff;
  font-size: 10px;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 12px;
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
  cursor: pointer;
}
.mockup__bubble::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 6px solid var(--blue);
}
.mockup__panel {
  width: 200px;
  border-left: 1px solid var(--border);
  background: #eff6ff;
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}
.mockup__panel-header {
  background: #93c5fd;
  padding: 8px 10px;
  font-size: 10px;
  font-weight: 700;
  color: #1e3a5f;
}
.mockup__panel-body {
  padding: 10px 8px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 10px;
  overflow: hidden;
}
.mockup__msg {
  padding: 6px 9px;
  border-radius: 10px;
  line-height: 1.5;
}
.mockup__msg--user {
  align-self: flex-end;
  background: var(--blue);
  color: #fff;
}
.mockup__msg--ai {
  align-self: flex-start;
  background: #dbeafe;
  color: #1e3a5f;
  border: 1px solid #93c5fd;
  font-size: 9.5px;
}

/* ── セクション共通 ───────────────────────────────── */
section { padding: 56px 0; }
.section-title {
  font-size: 21px;
  font-weight: 800;
  margin-bottom: 28px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border);
  color: var(--slate);
}

/* ── 概要 ─────────────────────────────────────────── */
.overview { border-bottom: 1px solid var(--border); }
.overview__text {
  color: var(--slate-mid);
  margin-bottom: 14px;
  max-width: 720px;
}
.overview__stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 32px;
}
.stat {
  text-align: center;
  padding: 20px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.stat__num {
  font-size: 28px;
  font-weight: 900;
  color: var(--blue-dark);
  margin-bottom: 4px;
}
.stat__label { font-size: 12px; color: var(--slate-light); }

/* ── 機能 ─────────────────────────────────────────── */
.features {
  background: var(--bg-soft);
  border-bottom: 1px solid var(--border);
}
.features__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.feature-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 20px;
  transition: box-shadow 0.18s, transform 0.18s;
}
.feature-card:hover {
  box-shadow: 0 6px 24px rgba(0,0,0,0.09);
  transform: translateY(-2px);
}
.feature-card__icon { font-size: 26px; margin-bottom: 12px; }
.feature-card__title {
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--slate);
}
.feature-card__desc { font-size: 13px; color: var(--slate-mid); line-height: 1.7; }

/* ── 使い方 ───────────────────────────────────────── */
.howto { border-bottom: 1px solid var(--border); }
.steps { display: flex; flex-direction: column; gap: 0; }
.step {
  display: flex;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
}
.step:last-child { border-bottom: none; }
.step__num {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--slate);
  color: #fff;
  font-weight: 800;
  font-size: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.step__title { font-size: 15px; font-weight: 700; margin-bottom: 5px; }
.step__desc  { font-size: 13px; color: var(--slate-mid); }

/* ── 詳細 ─────────────────────────────────────────── */
.details { background: var(--bg-soft); border-bottom: 1px solid var(--border); }
.details__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
}
.detail-item {
  padding: 16px 20px;
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.detail-item:nth-child(3n) { border-right: none; }
.detail-item:nth-last-child(-n+3) { border-bottom: none; }
.detail-item__label { font-size: 11px; color: var(--slate-light); font-weight: 700; text-transform: uppercase; letter-spacing: 0.05em; }
.detail-item__val   { font-size: 14px; font-weight: 600; color: var(--slate); }

/* ── プライバシー ─────────────────────────────────── */
.privacy { border-bottom: 1px solid var(--border); }
.privacy__box {
  display: flex;
  gap: 20px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}
.privacy__icon { font-size: 28px; flex-shrink: 0; }
.privacy__lead { font-weight: 700; margin-bottom: 10px; }
.privacy__list {
  padding-left: 18px;
  display: flex;
  flex-direction: column;
  gap: 5px;
}
.privacy__list li { font-size: 13px; color: var(--slate-mid); }

/* ── フッター ─────────────────────────────────────── */
.footer {
  background: var(--slate);
  color: #a0aec0;
  padding: 32px 0;
}
.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  flex-wrap: wrap;
  gap: 12px;
}
.footer__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 14px;
}
.footer__icon {
  width: 30px; height: 30px;
  border-radius: 7px;
  background: var(--blue);
  color: #fff;
  font-weight: 900;
  font-size: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.footer__links { display: flex; gap: 20px; }
.footer__links a { color: #a0aec0; font-size: 13px; }
.footer__links a:hover { color: #fff; }
.footer__copy { font-size: 12px; }

/* ── レスポンシブ ─────────────────────────────────── */
@media (max-width: 700px) {
  .hero__inner       { flex-direction: column; }
  .hero__icon        { width: 64px; height: 64px; font-size: 34px; }
  .features__grid    { grid-template-columns: 1fr; }
  .overview__stats   { grid-template-columns: repeat(2, 1fr); }
  .details__grid     { grid-template-columns: 1fr; }
  .detail-item       { border-right: none; }
  .gallery__grid     { flex-direction: column; }
  .gallery__thumbs   { flex-direction: row; width: 100%; }
  .mockup__content   { flex-direction: column; }
  .mockup__panel     { width: 100%; border-left: none; border-top: 1px solid var(--border); }
}