/* ヘッダー */
.student-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100vw;
  background: #f9f9fb; /* ページ背景と同じ */
  z-index: 1200;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: center; /* ロゴを中央に */
  height: 56px;
  padding: 0 16px;
}

.logo-center {
  display: flex;
  align-items: center;
  justify-content: center;
  flex: 1;
}

.logo {
  height: 48px;
  width: auto;
}

@media (min-width: 768px) {
  .logo {
    height: 52px;
  }
}

/* ハンバーガーアイコン */
.hamburger {
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  width: 44px;
  height: 44px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  cursor: pointer;
  z-index: 1301;
  border: none;
  background: transparent;
}

.bar {
  width: 24px;
  height: 2px;
  background: #222;
  margin: 3px 0;
  border-radius: 1px;
  transition: all 0.3s cubic-bezier(.4,2,.6,1);
}

.hamburger.open .bar1 {
  transform: rotate(45deg) translate(5px, 5px);
}
.hamburger.open .bar2 {
  opacity: 0;
}
.hamburger.open .bar3 {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* メニュー（フルスクリーンオーバーレイ風） */
.menu {
  position: fixed;
  top: 0;
  right: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(194, 137, 83, 0.96);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  z-index: 1300;
}

.menu.open {
  opacity: 1;
  pointer-events: auto;
}

.menu a {
  color: #ffffff;
  font-size: 1.2rem;
  font-weight: 600;
  text-decoration: none;
  margin: 10px 0;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  transition: transform 0.2s ease, color 0.2s ease;
}

.menu a:hover {
  transform: translateY(-2px);
  color: #ffdd99;
}