body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  background: linear-gradient(135deg, #0f172a, #1e293b, #111827);
  color: #f8fafc;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===== サイトヘッダー ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(15, 23, 42, 0.72);
  border-bottom: 1px solid rgba(148, 163, 184, 0.18);
  backdrop-filter: blur(14px);
}

.site-header__inner {
  width: min(1100px, 92%);
  margin: 0 auto;
  min-height: 64px;
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 10px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: #f8fafc;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: linear-gradient(135deg, #3b82f6, #6366f1);
  color: #fff;
  font-weight: 800;
  font-size: 14px;
  letter-spacing: 0.02em;
}

.brand__name {
  font-weight: 800;
  font-size: 20px;
  letter-spacing: 0.02em;
}

/* ===== メインナビ ===== */
.site-nav {
  display: flex;
  gap: 6px;
}

.site-nav__link {
  padding: 8px 14px;
  border-radius: 999px;
  color: #cbd5e1;
  text-decoration: none;
  font-size: 15px;
  font-weight: 600;
}

.site-nav__link:hover {
  color: #f8fafc;
  background: rgba(148, 163, 184, 0.12);
}

.site-nav__link[aria-current="page"] {
  color: #93c5fd;
  background: rgba(59, 130, 246, 0.18);
}

/* ===== アカウント（ヘッダー右側） ===== */
.account {
  margin-left: auto;
}

/* ホバー（またはクリック）で開くドロップダウン */
.dropdown {
  position: relative;
}

.dropdown__panel {
  display: none;
  position: absolute;
  right: 0;
  top: 100%;
  padding-top: 10px; /* ヘッダーとの隙間（ホバーが途切れない透明ブリッジ） */
  z-index: 60;
}

.dropdown:hover .dropdown__panel,
.dropdown:focus-within .dropdown__panel,
.dropdown.is-open .dropdown__panel {
  display: block;
}

.account__user {
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

.avatar-button {
  padding: 0;
  border: none;
  background: transparent;
  border-radius: 50%;
  cursor: pointer;
  line-height: 0;
}

.avatar-button:hover {
  background: transparent;
}

.avatar {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6, #6366f1);
  color: #fff;
  font-size: 16px;
  font-weight: 800;
  box-shadow: 0 0 0 2px transparent;
  transition: box-shadow 0.15s ease;
}

.avatar-button:hover .avatar,
.avatar-button[aria-expanded="true"] .avatar {
  box-shadow: 0 0 0 2px rgba(147, 197, 253, 0.6);
}

.account-menu {
  min-width: 220px;
  display: grid;
  gap: 2px;
  padding: 8px;
  border-radius: 14px;
  background: rgba(15, 23, 42, 0.96);
  border: 1px solid rgba(148, 163, 184, 0.22);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(14px);
}

/* ログイン用パネル */
.account-menu--login {
  min-width: 260px;
  gap: 10px;
  padding: 14px;
}

.account-menu__hint {
  margin: 0;
  color: #94a3b8;
  font-size: 12px;
}

.account-menu--login input {
  width: 100%;
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid rgba(148, 163, 184, 0.35);
  background: rgba(15, 23, 42, 0.6);
  color: #f8fafc;
  outline: none;
  font-size: 14px;
}

.account-menu--login input::placeholder {
  color: #94a3b8;
}

.account-menu--login input:focus {
  border-color: #60a5fa;
}

.account-menu__email {
  margin: 0 0 4px;
  padding: 8px 12px;
  color: #94a3b8;
  font-size: 13px;
  word-break: break-all;
  border-bottom: 1px solid rgba(148, 163, 184, 0.16);
}

.account-menu__item {
  display: block;
  width: 100%;
  padding: 10px 12px;
  border: none;
  border-radius: 10px;
  background: none;
  color: #e2e8f0;
  font-size: 14px;
  font-weight: 600;
  text-align: left;
  text-decoration: none;
  cursor: pointer;
}

.account-menu__item:hover {
  background: rgba(148, 163, 184, 0.14);
}

.account-menu__item--danger {
  color: #f87171;
}

/* ===== ボタン共通 ===== */
.btn {
  border: none;
  border-radius: 999px;
  background: #3b82f6;
  color: #fff;
  font-weight: 700;
  cursor: pointer;
}

.btn:hover {
  background: #2563eb;
}

.btn:disabled {
  opacity: 0.6;
  cursor: default;
}

.btn--sm {
  padding: 9px 18px;
  font-size: 14px;
}

.btn--ghost {
  background: rgba(148, 163, 184, 0.14);
  color: #e2e8f0;
}

.btn--ghost:hover {
  background: rgba(148, 163, 184, 0.26);
}

/* ===== メインラッパー ===== */
.app {
  flex: 1;
  width: min(1100px, 92%);
  margin: 0 auto;
  padding: 40px 0;
}

/* ===== ヒーロー ===== */
.hero {
  margin-bottom: 28px;
}

.logo {
  display: inline-block;
  margin: 0 0 14px;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(59, 130, 246, 0.18);
  color: #93c5fd;
  font-weight: 700;
  letter-spacing: 0.04em;
}

h1 {
  margin: 0;
  font-size: clamp(32px, 6vw, 64px);
  line-height: 1.05;
}

.subtitle {
  color: #cbd5e1;
  font-size: 18px;
  margin-top: 14px;
}

.auth-message {
  min-height: 22px;
  margin: 14px 0 0;
  font-size: 14px;
  color: #cbd5e1;
}

.auth-message.success {
  color: #4ade80;
}

.auth-message.error {
  color: #f87171;
}

/* ===== サイトフッター ===== */
.site-footer {
  margin-top: 40px;
  background: rgba(15, 23, 42, 0.72);
  border-top: 1px solid rgba(148, 163, 184, 0.18);
  backdrop-filter: blur(14px);
}

.site-footer__inner {
  width: min(1100px, 92%);
  margin: 0 auto;
  padding: 32px 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 24px;
}

.site-footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 18px;
}

.site-footer__tagline {
  margin: 0;
  color: #94a3b8;
  font-size: 14px;
}

.site-footer__nav {
  display: flex;
  gap: 18px;
  margin-left: auto;
}

.site-footer__nav a {
  color: #cbd5e1;
  text-decoration: none;
  font-size: 14px;
}

.site-footer__nav a:hover {
  color: #93c5fd;
}

.site-footer__copy {
  width: 100%;
  margin: 4px 0 0;
  color: #64748b;
  font-size: 13px;
}