/* ==========================================================================
   共通ヘッダースタイル (header.css)
   ========================================================================== */

:root {
  --color-base: #ffffff;
  --color-main: #009F00;
  --color-text-dark: #000000;
  --color-accent-red: #E70113;
  --color-bg-gray: #f0f0f0;
  --color-light-gray: #fafafa;
  --color-border-gray: #e0e0e0;
  --color-text-muted: #666666;
  --font-gothic: 'Noto Sans JP', sans-serif;
  --transition-smooth: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border-gray);
  transition: var(--transition-smooth);
  font-family: var(--font-gothic);
}

.header__container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 95px;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
  box-sizing: border-box;
}

.header__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.5rem;
  font-weight: 900;
  letter-spacing: 0.1em;
  text-decoration: none;
  color: var(--color-text-dark);
}

.header__logo-img {
  height: 72px;
  width: auto;
  object-fit: contain;
}

.header__nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.header__menu {
  display: flex;
  list-style: none;
  gap: 24px;
  margin: 0;
  padding: 0;
}

.header__menu-item {
  list-style: none;
  margin: 0;
  padding: 0;
}

.header__menu-link {
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 0;
  position: relative;
  color: var(--color-text-dark);
  text-decoration: none;
  transition: var(--transition-smooth);
}

.header__menu-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-main);
  transition: var(--transition-smooth);
}

.header__menu-link:hover {
  color: var(--color-main);
}

.header__menu-link:hover::after {
  width: 100%;
}

.header__actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  font-size: 0.85rem;
  font-weight: 700;
  border-radius: 0;
  cursor: pointer;
  transition: var(--transition-smooth);
  border: 1px solid transparent;
  text-decoration: none;
  box-sizing: border-box;
}

.btn--student {
  background-color: transparent;
  color: var(--color-text-dark);
  border-color: var(--color-text-dark);
}

.btn--student:hover {
  background-color: var(--color-text-dark);
  color: var(--color-base);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 30px;
  height: 21px;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 1100;
}

.menu-toggle span {
  width: 100%;
  height: 3px;
  background-color: var(--color-text-dark);
  transition: var(--transition-smooth);
}

/* モバイル対応レスポンシブスタイル */
@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }

  .header__nav {
    position: fixed;
    top: 95px;
    left: 100%;
    width: 100%;
    height: calc(100vh - 95px);
    background-color: #ffffff;
    flex-direction: column;
    padding: 40px 24px;
    gap: 40px;
    transition: var(--transition-smooth);
    box-shadow: 0 4px 10px rgba(0,0,0,0.05);
  }

  .header__nav.active {
    left: 0;
  }

  .header__menu {
    flex-direction: column;
    align-items: center;
    gap: 32px;
  }

  .header__actions {
    flex-direction: column;
    width: 100%;
    gap: 16px;
  }

  .header__actions .btn {
    width: 100%;
  }
}

/* ==========================================================================
   管理画面テーブル崩壊防止用緊急スタイル
   ========================================================================== */
.admin-table {
  border-collapse: separate !important;
  border-spacing: 0 !important;
}

.admin-table thead {
  position: static !important;
  background-color: #f8fafc !important;
}

.admin-table thead tr {
  background-color: #f8fafc !important;
}

.admin-table th {
  position: sticky !important;
  top: 95px !important;
  z-index: 100 !important;
  background-color: #f8fafc !important;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05) !important;
}

.admin-table tbody {
  position: static !important;
}