:root {
  --ink: #17212b;
  --muted: #64707d;
  --paper: #fffdf8;
  --surface: #ffffff;
  --line: #dbe6e9;
  --aqua: #00a6a6;
  --aqua-dark: #007981;
  --coral: #ff6b4a;
  --sun: #ffc84d;
  --mint: #e8fbf8;
  --peach: #fff0eb;
  --shadow: 0 16px 38px rgba(23, 33, 43, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--ink);
  background: linear-gradient(180deg, #e9fbf8 0, #fffdf8 520px), var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  line-height: 1.85;
}

a {
  color: inherit;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 253, 248, 0.92);
  border-bottom: 1px solid rgba(219, 230, 233, 0.9);
  backdrop-filter: blur(12px);
}

.header-inner,
.container {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.header-inner {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  text-decoration: none;
  display: inline-flex;
  flex-direction: column;
  line-height: 1.1;
}

.brand strong {
  font-size: 24px;
  letter-spacing: 0.02em;
}

.brand span {
  margin-top: 5px;
  color: var(--muted);
  font-size: 12px;
}

.nav {
  display: flex;
  gap: 18px;
  color: #34404c;
  font-size: 14px;
  font-weight: 700;
}

.nav a {
  text-decoration: none;
}

.hero {
  padding: 44px 0 46px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 1.05fr);
  gap: 36px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  gap: 8px;
  margin: 0 0 16px;
  padding: 8px 12px;
  color: #fff;
  background: var(--aqua);
  border-radius: 999px;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.04em;
}

h1,
.page-title {
  margin: 0;
  font-size: clamp(34px, 5vw, 58px);
  line-height: 1.18;
  letter-spacing: 0;
}

h1 span {
  display: inline-block;
  margin-top: 8px;
  font-size: 0.72em;
}

.lead {
  margin: 22px 0 0;
  color: #34404c;
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 18px;
  border-radius: 8px;
  border: 1px solid transparent;
  text-decoration: none;
  font-weight: 800;
}

.button-primary {
  color: #fff;
  background: var(--coral);
  box-shadow: 0 12px 24px rgba(255, 107, 74, 0.18);
}

.button-secondary {
  color: var(--aqua-dark);
  background: #fff;
  border-color: var(--line);
}

.hero-image {
  overflow: hidden;
  border: 1px solid rgba(0, 166, 166, 0.18);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.hero-image img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.section {
  padding: 38px 0;
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 20px;
}

h2 {
  margin: 0;
  font-size: clamp(26px, 3.4vw, 36px);
  line-height: 1.3;
}

.section-head p,
.muted {
  color: var(--muted);
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 10px 24px rgba(23, 33, 43, 0.05);
}

.card-accent {
  border-top: 5px solid var(--aqua);
}

.card:nth-child(2n).card-accent {
  border-top-color: var(--coral);
}

.card:nth-child(3n).card-accent {
  border-top-color: var(--sun);
}

.card h3 {
  margin: 0 0 8px;
  font-size: 20px;
  line-height: 1.42;
}

.card p {
  margin: 0;
  color: var(--muted);
}

.article-list {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(260px, 0.8fr);
  gap: 18px;
}

.article-card {
  display: block;
  padding: 24px;
  color: inherit;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  text-decoration: none;
  box-shadow: var(--shadow);
}

.article-card strong {
  display: block;
  margin: 0 0 10px;
  font-size: 24px;
  line-height: 1.35;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.tag {
  display: inline-flex;
  padding: 5px 10px;
  color: var(--aqua-dark);
  background: var(--mint);
  border-radius: 999px;
  font-size: 12px;
  font-weight: 800;
}

.cta-band {
  margin: 42px 0 0;
  padding: 28px;
  color: #10252a;
  background: linear-gradient(135deg, var(--sun), #ffe38b);
  border-radius: 8px;
  box-shadow: 0 14px 34px rgba(255, 200, 77, 0.18);
}

.cta-band h2 {
  font-size: 28px;
}

.cta-band p {
  margin: 10px 0 0;
}

.site-footer {
  margin-top: 56px;
  padding: 34px 0;
  color: #46525f;
  background: #f4faf8;
  border-top: 1px solid var(--line);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 12px;
  font-size: 14px;
}

.footer-links a {
  color: inherit;
}

.article-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 34px;
  align-items: start;
  padding-top: 34px;
}

.article-main {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: min(6vw, 44px);
  box-shadow: var(--shadow);
}

.article-main h1 {
  padding-bottom: 20px;
  border-bottom: 6px solid var(--sun);
  font-size: clamp(30px, 4.4vw, 46px);
}

.article-main h2 {
  margin: 54px 0 18px;
  padding: 0 0 10px 16px;
  border-bottom: 2px solid var(--line);
  border-left: 7px solid var(--coral);
  font-size: clamp(24px, 3vw, 30px);
}

.article-main h3 {
  margin: 34px 0 12px;
  color: var(--aqua-dark);
  font-size: 22px;
  line-height: 1.45;
}

.article-main h4 {
  margin: 30px 0 10px;
  padding: 10px 14px;
  background: var(--mint);
  border-left: 4px solid var(--aqua);
  border-radius: 6px;
  font-size: 18px;
}

.article-main p {
  margin: 0 0 18px;
}

.ad-notice {
  display: inline-block;
  margin: 0 0 18px;
  padding: 6px 10px;
  color: #5b6673;
  background: #f5f7f8;
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 13px;
  line-height: 1.5;
}

.affiliate-cta {
  margin: 16px 0 26px;
  padding: 13px 16px;
  color: #10252a;
  background: linear-gradient(135deg, var(--sun), #ffe38b);
  border: 1px solid #f0b72c;
  border-radius: 8px;
  box-shadow: 0 8px 20px rgba(255, 173, 40, 0.18);
  font-weight: 800;
}

.sidebar {
  position: sticky;
  top: 88px;
}

.sidebar-box {
  margin-bottom: 16px;
  padding: 18px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.sidebar-box h2 {
  margin: 0 0 10px;
  font-size: 18px;
}

.sidebar-box a {
  display: block;
  margin: 8px 0;
  color: var(--aqua-dark);
  font-weight: 800;
  text-decoration: none;
}

.legal-page {
  max-width: 820px;
  padding-top: 42px;
}

.legal-page h1 {
  margin-bottom: 22px;
  font-size: clamp(30px, 4vw, 44px);
}

.legal-page h2 {
  margin: 34px 0 12px;
  font-size: 24px;
}

@media (max-width: 860px) {
  .hero-grid,
  .article-list,
  .article-shell {
    grid-template-columns: 1fr;
  }

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

  .sidebar {
    position: static;
  }
}

@media (max-width: 640px) {
  .header-inner,
  .container {
    width: min(100% - 32px, 1120px);
  }

  .header-inner {
    min-height: 64px;
  }

  .nav {
    display: none;
  }

  .hero {
    padding-top: 28px;
  }

  .hero-actions {
    display: grid;
  }

  .button {
    width: 100%;
  }

  .article-main {
    padding: 24px 18px;
  }
}