:root {
    --bg-color: #e6eef4;
    --light-shadow: #ffffff;
    --dark-shadow: #c1d3ea;
    --accent-color: #4dabf7;
    --error-bg: #ffdada;
    --error-color: #ff8787;
    --text-main: #4a5568;
    --text-sub: #a0aec0;
}

* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Hiragino Kaku Gothic ProN', 'Meiryo', sans-serif; user-select: none; }
body { background-color: var(--bg-color); display: flex; justify-content: center; align-items: center; height: 100vh; overflow: hidden; color: var(--text-main); }

.container { 
    background-color: var(--bg-color); padding: 50px 40px; border-radius: 50px; 
    box-shadow: 20px 20px 60px var(--dark-shadow), -20px -20px 60px var(--light-shadow); 
    width: 620px; min-height: 640px; text-align: center; position: relative;
    transition: background-color 0.15s ease;
    display: flex; flex-direction: column;
}

.container.error-flash { background-color: var(--error-bg); }
.screen { display: flex; flex-direction: column; height: 100%; }
.hidden { display: none !important; }

/* 設定グループの余白改善 */
.mode-select-area { margin-bottom: 30px; }
.setting-group { margin-top: 20px; transition: opacity 0.3s; }

.label { 
    font-size: 0.85rem; color: var(--text-sub); 
    margin-bottom: 20px; font-weight: bold; letter-spacing: 2px;
}

.mode-options, .options { display: flex; justify-content: center; gap: 20px; }

.countdown-text { font-size: 8rem; font-weight: 800; color: var(--accent-color); margin: auto; }

.title { font-size: 2.2rem; letter-spacing: 6px; margin-bottom: 40px; color: var(--accent-color); font-weight: 800; }

.mode-btn, .time-btn, .q-limit-btn, .cat-btn {
    padding: 14px 26px; border-radius: 16px; border: none; background: var(--bg-color);
    box-shadow: 6px 6px 12px var(--dark-shadow), -6px -6px 12px var(--light-shadow);
    cursor: pointer; font-weight: 600; transition: 0.3s; color: var(--text-main);
}
.mode-btn.active, .time-btn.active, .q-limit-btn.active, .cat-btn.active { box-shadow: inset 4px 4px 8px var(--dark-shadow), inset -4px -4px 8px var(--light-shadow); color: var(--accent-color); }
.category-select-area { margin-bottom: 24px; }
.category-options { display: flex; justify-content: center; gap: 16px; }

/* 下部に十分な余白を設けたスタートボタン */
.action-btn { 
    margin-top: 60px; /* 上部とのスペースを大幅に確保 */
    padding: 22px; border-radius: 20px; border: none; background: var(--accent-color); 
    color: white; font-size: 1.2rem; font-weight: 700; cursor: pointer; 
    box-shadow: 6px 6px 15px #b5c7e0; transition: transform 0.1s;
}
.action-btn:active { transform: scale(0.98); }

.stats-bar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 30px; color: var(--text-sub); }
.stop-btn { padding: 8px 15px; border-radius: 10px; border: none; background: var(--bg-color); color: var(--error-color); font-size: 0.75rem; font-weight: bold; cursor: pointer; box-shadow: 4px 4px 8px var(--dark-shadow), -4px -4px 8px var(--light-shadow); }

.display-area { background: var(--bg-color); padding: 45px 20px; border-radius: 40px; box-shadow: inset 8px 8px 16px var(--dark-shadow), inset -8px -8px 16px var(--light-shadow); margin-bottom: 40px; }
.kanji-target { font-size: 2rem; font-weight: 700; margin-bottom: 10px; }
.kana-target { font-size: 1.1rem; color: var(--text-sub); margin-bottom: 20px; }
.romaji-target { font-size: 1.6rem; letter-spacing: 3px; font-weight: bold; min-height: 1.8em; }

.typed { color: var(--accent-color); }
.untyped { color: var(--text-sub); opacity: 0.3; }
#type-input { position: absolute; opacity: 0; pointer-events: none; }
.stats-footer { display: flex; justify-content: center; margin-top: auto; }

.combo-area { display: flex; align-items: center; gap: 14px; width: 100%; }
.combo-label { font-size: 0.75rem; font-weight: 700; letter-spacing: 2px; color: var(--text-sub); white-space: nowrap; }
.combo-track { flex: 1; height: 8px; border-radius: 4px; background: var(--bg-color); box-shadow: inset 3px 3px 6px var(--dark-shadow), inset -3px -3px 6px var(--light-shadow); overflow: hidden; }
.combo-fill { height: 100%; width: 0%; border-radius: 4px; background: var(--accent-color); transition: width 0.08s ease; }
.combo-fill.bonus { background: #f5a623; transition: none; }

.result-card { background: var(--bg-color); padding: 40px; border-radius: 35px; box-shadow: inset 6px 6px 12px var(--dark-shadow), inset -6px -6px 12px var(--light-shadow); margin-bottom: 40px; }
.res-item { display: flex; flex-direction: column; margin-bottom: 25px; }
.res-item strong { font-size: 3.5rem; color: var(--accent-color); line-height: 1; }
.res-item.secondary { flex-direction: row; justify-content: space-between; align-items: center; margin-bottom: 12px; border-bottom: 1px solid var(--dark-shadow); padding-bottom: 8px; }
.kpm-value-group { display: flex; align-items: center; gap: 10px; }
.kpm-level { font-weight: 700; color: var(--accent-color); font-size: 1rem; letter-spacing: 1px; }

.kpm-message { background: var(--bg-color); border-radius: 20px; padding: 20px 24px; margin-bottom: 20px; box-shadow: inset 4px 4px 8px var(--dark-shadow), inset -4px -4px 8px var(--light-shadow); text-align: left; }
.kpm-msg-title { font-size: 0.95rem; font-weight: 700; color: var(--text-main); margin-bottom: 6px; }
.kpm-msg-body { font-size: 0.82rem; color: var(--text-sub); line-height: 1.7; }

.res-level { margin-bottom: 20px; }
.res-level span { display: inline-block; padding: 6px 20px; border-radius: 20px; font-size: 0.9rem; font-weight: 700; letter-spacing: 2px; background: var(--bg-color); box-shadow: 4px 4px 8px var(--dark-shadow), -4px -4px 8px var(--light-shadow); color: var(--text-sub); }
.res-level span[data-rank="5"] { color: #f5a623; }
.res-level span[data-rank="4"] { color: #7b61ff; }
.res-level span[data-rank="3"] { color: var(--accent-color); }
.res-level span[data-rank="2"] { color: #4caf50; }