/* 🌍 画面全体 */
body {
    font-family: 'Arial', sans-serif;
    background: radial-gradient(circle, #1a1a2e, #16213e);
    color: white;
    text-align: center;
    margin: 0;
    padding: 20px;
}

/* 📌 ヘッダー */
.header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 1rem 2rem;
    margin: 2rem auto 1rem auto;
    max-width: 600px;
}

h1 {
    font-size: 24px;
}

/* 📌 タブメニュー */
.tab-menu {
    display: flex;
    justify-content: center;
    margin-top: 20px;
    gap: 1rem;
    margin-bottom: 1rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.tab-button {
    padding: 10px 20px;
    font-size: 16px;
    border: 2px solid white;
    background: rgba(255, 255, 255, 0.1);
    cursor: pointer;
    transition: background 0.3s, border-color 0.3s;
    border-radius: 5px;
    color: white;
}

.tab-button:hover {
    background: rgba(255, 255, 255, 0.2);
}

.tab-button.active {
    background: #007bff;
    border-color: #0056b3;
}

/* 📌 情報エリア */
.info-tab {
    display: none;
    margin-top: 20px;
    padding: 1.5rem;
    margin: 0 auto 2rem auto;
    max-width: 600px;
    min-height: 120px;
}

.info-tab.active {
    display: block;
}

/* 📌 情報カード */
.custom-card {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    padding: 20px;
    margin: 10px auto;
    backdrop-filter: blur(10px);
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.3);
}

/* 🚀 ぐるぐる回る地球 */
.spin-slow {
    display: inline-block;
    animation: spin 8s linear infinite;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

/* 📱 スマホ対応 */
@media (max-width: 600px) {
    h1 {
        font-size: 20px;
    }
    .tab-button {
        font-size: 14px;
        padding: 8px 16px;
    }
}

/* ガラスUI共通 */
.glass {
  background: rgba(255, 255, 255, 0.2); /* 半透明白 */
  border-radius: 16px;
  box-shadow: 0 4px 32px 0 rgba(0,0,0,0.12);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.3);
}