* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;

  color: #1f2937;
  background-color: #ffffff;

  font-family:
    Arial,
    "Hiragino Kaku Gothic ProN",
    "Yu Gothic",
    Meiryo,
    sans-serif;

  line-height: 1.7;
}

a {
  color: inherit;
  text-decoration: none;
}

/* =========================
   ヘッダー
========================= */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;

  background-color: rgba(255, 255, 255, 0.95);
  border-bottom: 1px solid #e5e7eb;

  backdrop-filter: blur(10px);
}

.header-inner {
  width: 100%;
  max-width: 1100px;

  margin: 0 auto;
  padding: 16px 20px;

  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  color: #2563eb;

  font-size: 22px;
  font-weight: bold;
  letter-spacing: 0.08em;
}

.navigation {
  display: flex;
  gap: 24px;

  font-size: 15px;
  font-weight: bold;
}

.navigation a {
  transition: color 0.2s;
}

.navigation a:hover {
  color: #2563eb;
}

.menu-button {
  display: none;

  border: none;
  background: none;

  font-size: 26px;
  cursor: pointer;
}

/* =========================
   メインビジュアル
========================= */

.hero {
  min-height: 620px;

  padding: 100px 20px;

  display: flex;
  align-items: center;

  background:
    linear-gradient(
      135deg,
      rgba(37, 99, 235, 0.94),
      rgba(14, 116, 144, 0.9)
    );
}

.hero-content {
  width: 100%;
  max-width: 1100px;

  margin: 0 auto;

  color: white;
}

.hero-label {
  margin-bottom: 15px;

  font-size: 14px;
  font-weight: bold;
  letter-spacing: 0.15em;
}

.hero h1 {
  margin: 0;

  font-size: clamp(38px, 7vw, 68px);
  line-height: 1.25;
}

.hero-description {
  max-width: 720px;

  margin-top: 25px;

  font-size: 18px;
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;

  margin-top: 32px;
}

/* =========================
   ボタン
========================= */

.button {
  display: inline-block;

  padding: 13px 24px;

  border-radius: 10px;

  font-weight: bold;

  transition:
    transform 0.2s,
    opacity 0.2s;
}

.button:hover {
  transform: translateY(-2px);
  opacity: 0.9;
}

.primary-button {
  background-color: #2563eb;
  color: white;
}

.secondary-button {
  border: 2px solid white;
  color: white;
}

.game-button {
  background-color: #dc2626;
  color: white;
}

/* =========================
   共通セクション
========================= */

.section {
  padding: 90px 20px;
}

.gray-section {
  background-color: #f3f4f6;
}

.section-inner {
  width: 100%;
  max-width: 1100px;

  margin: 0 auto;
}

.section-label {
  margin-bottom: 5px;

  color: #2563eb;

  font-size: 13px;
  font-weight: bold;
  letter-spacing: 0.15em;
}

.section h2 {
  margin-top: 0;
  margin-bottom: 35px;

  font-size: 34px;
}

/* =========================
   自己紹介
========================= */

.about-box {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 40px;
  align-items: center;

  padding: 35px;

  background-color: #f8fafc;
  border-radius: 18px;
}

.profile-image-wrap {
  width: 150px;
  height: 150px;

  margin: 0 auto;

  overflow: hidden;

  border-radius: 50%;
  background-color: #e5e7eb;

  box-shadow:
    0 8px 22px rgba(0, 0, 0, 0.12);
}
.about-text p:first-child {
  font-size: 20px;
  font-weight: bold;
}

/* プロフィール画像 */

.profile-image-wrap {
  width: 150px;
  height: 150px;

  overflow: hidden;

  border-radius: 50%;

  background-color: #e5e7eb;

  box-shadow:
    0 8px 22px rgba(0, 0, 0, 0.12);
}

.profile-image {
  width: 100%;
  height: 100%;

  display: block;

  object-fit: cover;
  object-position: 55% center;
}
/* SNSリンク */

.social-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;

  margin-top: 22px;
}

.social-link {
  display: inline-block;

  padding: 9px 16px;

  border: 1px solid #2563eb;
  border-radius: 999px;

  color: #2563eb;

  font-size: 14px;
  font-weight: bold;

  transition:
    background-color 0.2s,
    color 0.2s,
    transform 0.2s;
}

.social-link:hover {
  background-color: #2563eb;
  color: white;

  transform: translateY(-2px);
}

/* =========================
   発信内容カード
========================= */

.card-grid {
  display: grid;
  grid-template-columns:
    repeat(2, minmax(0, 1fr));

  gap: 20px;
}

.content-card {
  padding: 28px;

  background-color: white;
  border-radius: 16px;

  box-shadow:
    0 8px 25px rgba(0, 0, 0, 0.06);
}

.card-icon {
  font-size: 42px;
}

.content-card h3 {
  margin-bottom: 10px;

  font-size: 22px;
}

/* =========================
   ブログ・お問い合わせ
========================= */

.link-box,
.contact-box {
  padding: 38px;

  background-color: #f8fafc;
  border-radius: 18px;

  text-align: center;
}

.link-box h3 {
  font-size: 25px;
}

/* =========================
   おすすめ記事
========================= */

.article-grid {
  display: grid;
  grid-template-columns:
    repeat(3, minmax(0, 1fr));

  gap: 20px;

  margin-top: 30px;
}

.article-card {
  display: flex;
  flex-direction: column;

  padding: 25px;

  background-color: #ffffff;
  border: 1px solid #e5e7eb;
  border-radius: 16px;

  box-shadow:
    0 7px 22px rgba(0, 0, 0, 0.06);

  transition:
    transform 0.2s,
    box-shadow 0.2s;
}

.article-card:hover {
  transform: translateY(-4px);

  box-shadow:
    0 12px 30px rgba(0, 0, 0, 0.1);
}

.article-category {
  align-self: flex-start;

  padding: 5px 10px;

  border-radius: 999px;

  background-color: #dbeafe;
  color: #1d4ed8;

  font-size: 12px;
  font-weight: bold;
}

.article-card h3 {
  margin-bottom: 10px;

  font-size: 21px;
  line-height: 1.5;
}

.article-card p {
  flex-grow: 1;

  color: #4b5563;
}

.article-card a {
  margin-top: 10px;

  color: #2563eb;

  font-weight: bold;
}

/* =========================
   ゲーム
========================= */

.game-box {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 35px;
  align-items: center;

  padding: 35px;

  background-color: white;
  border-radius: 18px;
}

.game-description h3 {
  font-size: 26px;
}

.game-preview {
  min-height: 260px;

  display: flex;
  align-items: center;
  justify-content: center;

  border-radius: 18px;

  background:
    linear-gradient(
      135deg,
      #dcfce7,
      #bfdbfe
    );
}

.game-preview span {
  font-size: 100px;
}

/* =========================
   フッター
========================= */

.site-footer {
  padding: 30px 20px;

  background-color: #111827;
  color: white;

  text-align: center;
}

/* =========================
   上へ戻るボタン
========================= */

.top-button {
  position: fixed;
  right: 20px;
  bottom: 20px;

  width: 48px;
  height: 48px;

  display: none;
  align-items: center;
  justify-content: center;

  border: none;
  border-radius: 50%;

  background-color: #2563eb;
  color: white;

  font-size: 22px;
  font-weight: bold;

  cursor: pointer;

  box-shadow:
    0 5px 15px rgba(0, 0, 0, 0.18);
}

/* =========================
   スマートフォン表示
========================= */
/* =========================
   固定ページ
========================= */

.subpage-home-link {
  color: #2563eb;

  font-size: 14px;
  font-weight: bold;
}

.subpage-home-link:hover {
  text-decoration: underline;
}

/* 固定ページのタイトル */
.subpage-hero {
  padding: 80px 20px;

  background:
    linear-gradient(
      135deg,
      #eff6ff,
      #ecfeff
    );
}

.subpage-inner {
  width: 100%;
  max-width: 900px;

  margin: 0 auto;
}

.subpage-hero h1 {
  margin-top: 5px;
  margin-bottom: 15px;

  font-size: clamp(32px, 6vw, 48px);
}

.subpage-hero p:last-child {
  max-width: 700px;

  color: #4b5563;
}

/* プライバシーポリシー */
.legal-section {
  padding: 70px 20px;
}

.legal-content {
  width: 100%;
  max-width: 900px;

  margin: 0 auto;
}

.legal-content h2 {
  margin-top: 55px;
  margin-bottom: 15px;

  padding-bottom: 10px;

  border-bottom: 2px solid #dbeafe;

  font-size: 24px;
}

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

.legal-content p {
  margin: 0 0 16px;

  color: #374151;
}

.legal-date {
  margin-top: 60px;
  padding-top: 20px;

  border-top: 1px solid #e5e7eb;

  color: #6b7280;
}

/* 運営者プロフィール */
.operator-profile {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 40px;
  align-items: center;

  padding: 35px;

  background-color: #f8fafc;
  border-radius: 18px;
}

.operator-description h2 {
  margin-top: 0;
  margin-bottom: 15px;
}

.operator-description p {
  color: #374151;
}

/* 運営者リンク */
.operator-links {
  display: grid;
  grid-template-columns:
    repeat(2, minmax(0, 1fr));

  gap: 16px;
}

.operator-link-card {
  display: flex;
  flex-direction: column;

  padding: 22px;

  border: 1px solid #e5e7eb;
  border-radius: 14px;

  background-color: #ffffff;

  transition:
    transform 0.2s,
    box-shadow 0.2s,
    border-color 0.2s;
}

.operator-link-card:hover {
  transform: translateY(-3px);

  border-color: #93c5fd;

  box-shadow:
    0 8px 24px rgba(0, 0, 0, 0.08);
}

.operator-link-card strong {
  margin-bottom: 4px;

  color: #2563eb;

  font-size: 18px;
}

.operator-link-card span {
  color: #4b5563;
}

/* フッターリンク */
.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;

  margin-bottom: 15px;
}

.footer-links a {
  color: #d1d5db;

  font-size: 14px;
}

.footer-links a:hover {
  color: #ffffff;
  text-decoration: underline;
}

@media screen and (max-width: 750px) {

  .menu-button {
    display: block;
  }

  .navigation {
    position: absolute;
    top: 68px;
    right: 15px;
    left: 15px;

    display: none;
    flex-direction: column;
    gap: 0;

    padding: 15px;

    background-color: white;
    border: 1px solid #e5e7eb;
    border-radius: 12px;

    box-shadow:
      0 10px 25px rgba(0, 0, 0, 0.12);
  }

  .navigation.is-open {
    display: flex;
  }

  .navigation a {
    padding: 12px;
  }

  .hero {
    min-height: 560px;
    padding-top: 75px;
  }

  .hero h1 {
    font-size: 40px;
  }

  .hero-description {
    font-size: 16px;
  }

  .section {
    padding: 65px 16px;
  }

  .section h2 {
    font-size: 29px;
  }

  .about-box {
    grid-template-columns: 1fr;

    text-align: center;
  }

  .profile-image-wrap {
    margin: 0 auto;
  }

  .social-links {
    justify-content: center;
  }

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

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

  .game-box {
    grid-template-columns: 1fr;
  }

  .game-preview {
    min-height: 210px;
  }
  .operator-profile {
    grid-template-columns: 1fr;

    text-align: center;
  }

  .operator-profile .profile-image-wrap {
    margin: 0 auto;
  }

  .operator-links {
    grid-template-columns: 1fr;
  }

  .subpage-hero {
    padding: 60px 16px;
  }

  .legal-section {
    padding: 55px 16px;
  }

  .legal-content h2 {
    margin-top: 45px;

    font-size: 22px;
  }
}

/* =========================
   小さいスマートフォン
========================= */

@media screen and (max-width: 480px) {

  .header-inner {
    padding: 14px 16px;
  }

  .site-logo {
    font-size: 20px;
  }

  .hero {
    min-height: 520px;
    padding: 65px 16px;
  }

  .hero h1 {
    font-size: 34px;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .hero-buttons .button {
    width: 100%;

    text-align: center;
  }

  .about-box,
  .link-box,
  .contact-box,
  .game-box {
    padding: 25px 20px;
  }

  .profile-image-wrap {
    width: 130px;
    height: 130px;
  }

  .social-link {
    width: 100%;

    text-align: center;
  }

  .game-preview span {
    font-size: 80px;
  }
}

/* =========================
   404ページ
========================= */

.error-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 20px;
  background: linear-gradient(
    135deg,
    #2f6fed,
    #2d8fa3
  );
}

.error-box {
  width: 100%;
  max-width: 720px;
  padding: 60px 40px;
  text-align: center;
  background: #ffffff;
  border-radius: 24px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.18);
}

.error-code {
  margin: 0;
  font-size: clamp(72px, 14vw, 140px);
  font-weight: 800;
  line-height: 1;
  color: #2f6fed;
}

.error-box h1 {
  margin-top: 12px;
  font-size: clamp(28px, 5vw, 42px);
}

.error-message {
  margin: 12px 0;
  line-height: 1.8;
  color: #666666;
}

.error-buttons {
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 30px;
}

@media screen and (max-width: 480px) {

  .error-box {
    padding: 40px 24px;
  }

  .error-buttons {
    flex-direction: column;
  }

  .error-buttons .button {
    width: 100%;
  }
}