/* リセット */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Helvetica Neue', sans-serif;
    background: linear-gradient(135deg, #e0eafc, #cfdef3);
    color: #000;
    min-height: 100vh;
}

/* ヘッダー */
header {
    text-align: center;
    padding: 2.5rem 1rem;
    background: linear-gradient(135deg, #667eea, #764ba2); /* 青系グラデーション */
    border-bottom-left-radius: 25px;
    border-bottom-right-radius: 25px;
    box-shadow: 0 6px 20px rgba(0,0,0,0.3);
    position: relative;
    overflow: hidden;
}

header h1 {
    font-size: 3rem;
    font-weight: 900;
    letter-spacing: 2px;
    color: #fff;
    text-shadow: 2px 2px 8px rgba(0,0,0,0.3);
    opacity: 0;
    transform: translateY(-20px) scale(0.9);
    animation: headerAnim 1.8s ease forwards;
    animation-delay: 0.2s;
}

@keyframes headerAnim {
    0% {opacity: 0; transform: translateY(-20px) scale(0.9);}
    60% {opacity: 1; transform: translateY(5px) scale(1.05);}
    100% {opacity: 1; transform: translateY(0) scale(1);}
}

main {
    max-width: 720px;
    margin: 2rem auto;
    padding: 1rem;
}

/* セクション見出し */
h2 {
    color: #333;
    font-weight: 700;
    margin-bottom: 0.6rem;
    border-left: 6px solid #667eea;
    padding-left: 0.7rem;
}

/* プルダウン装飾 */
select, input[type="number"] {
    margin-left: 0.5rem;
    padding: 0.6rem 1.2rem;
    font-size: 1rem;
    border-radius: 12px;
    border: none;
    background: linear-gradient(145deg, #ffffff, #d3d3d3);
    box-shadow: inset 2px 2px 5px rgba(0,0,0,0.15);
    cursor: pointer;
    transition: all 0.3s ease;
}

select:hover, input[type="number"]:hover {
    box-shadow: inset 2px 2px 5px rgba(0,0,0,0.25);
}

/* ラベル */
label {
    display: block;
    margin: 0.8rem 0;
    font-weight: 500;
}

/* ボタン */
button {
    margin: 0.3rem 0.3rem;
    padding: 0.6rem 1.2rem;
    border: none;
    border-radius: 12px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 14px rgba(0,0,0,0.3);
}

/* クイズ/暗記ボックス */
#quizContainer, #memorizeBox {
    margin: 1rem 0;
    padding: 1.5rem;
    background: linear-gradient(145deg, #ffffff, #f1f1f1);
    border-radius: 16px;
    box-shadow: 0 6px 18px rgba(0,0,0,0.2);
    font-size: 1.1rem;
}

/* クイズ問題 */
.questionItem {
    margin-bottom: 1rem;
    padding: 1rem;
    background: linear-gradient(135deg, #89f7fe, #66a6ff); /* 青系グラデーション */
    color: black;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
    cursor: pointer;
    transition: all 0.3s ease;
}

.questionItem:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(0,0,0,0.3);
}

/* 非表示用 */
.hidden {
    display: none;
}

/* 答えの文字 */
.answer {
    font-weight: 600;
    color: #000;
}

/* 結果表示 */
.result {
    margin-top: 0.3rem;
    font-weight: bold;
}

/* 苦手ボタン */
.weakBtn {
    background: linear-gradient(135deg, #ff7e5f, #feb47b);
    margin-left: 0.5rem;
    font-size: 0.9rem;
}

/* 選択肢ボタン */
.choiceBtn {
    background: linear-gradient(135deg, #43cea2, #185a9d);
    color: white;
    font-weight: 500;
    margin-top: 0.3rem;
}

/* 自由入力欄装飾 */
.userInput {
    padding: 0.5rem 1rem;
    border-radius: 12px;
    border: none;
    background: linear-gradient(145deg, #f0f0f0, #dcdcdc);
    box-shadow: inset 2px 2px 6px rgba(0,0,0,0.2);
    font-size: 1rem;
    width: 70%;
    margin-right: 0.5rem;
    transition: all 0.3s ease;
}

.userInput:focus {
    outline: none;
    box-shadow: inset 2px 2px 6px rgba(0,0,0,0.3), 0 0 8px rgba(102,126,234,0.5);
    background: linear-gradient(145deg, #ffffff, #e0e0e0);
}