.game-2a1b {
    max-width: 560px;
    margin: 20px auto;
    font-family: -apple-system, "Segoe UI", "PingFang TC", "Microsoft JhengHei", sans-serif;
    color: #2b2b2b;
}
.game-2a1b .title-2a1b {
    text-align: center;
    margin: 0 0 10px;
    font-size: 2rem;
    letter-spacing: 2px;
}
.game-2a1b .rules-2a1b {
    background: #f5f7fa;
    border-radius: 10px;
    padding: 12px 16px;
    font-size: 0.9rem;
    line-height: 1.6;
    color: #555;
}
.game-2a1b code {
    background: #e8edf3;
    padding: 1px 5px;
    border-radius: 4px;
    font-size: 0.9em;
}

/* 模式切換列 */
.mode-bar-2a1b {
    display: flex;
    gap: 10px;
    margin: 18px 0;
}
.mode-btn-2a1b {
    flex: 1;
    padding: 12px 8px;
    border: 2px solid #d0d7de;
    background: #fff;
    border-radius: 10px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.15s;
}
.mode-btn-2a1b:hover { border-color: #8b9cb3; }
.mode-btn-2a1b.active {
    background: #4a6fa5;
    border-color: #4a6fa5;
    color: #fff;
}

/* 通用面板 */
.panel-2a1b { animation: fade-2a1b 0.2s; }
@keyframes fade-2a1b { from { opacity: 0; } to { opacity: 1; } }

.input-row-2a1b {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 12px;
}
.game-2a1b input[type="text"] {
    flex: 1;
    min-width: 140px;
    padding: 10px 12px;
    font-size: 1.2rem;
    letter-spacing: 6px;
    text-align: center;
    border: 2px solid #d0d7de;
    border-radius: 8px;
}
.game-2a1b input[type="text"]:focus {
    outline: none;
    border-color: #4a6fa5;
}
.game-2a1b button {
    padding: 10px 16px;
    font-size: 1rem;
    border: none;
    border-radius: 8px;
    background: #4a6fa5;
    color: #fff;
    cursor: pointer;
    transition: background 0.15s;
}
.game-2a1b button:hover { background: #3a5a8a; }
.game-2a1b button:disabled { background: #b9c2cf; cursor: not-allowed; }
.game-2a1b button.secondary-2a1b { background: #8a93a0; }
.game-2a1b button.secondary-2a1b:hover { background: #6f7884; }

.hint-2a1b {
    background: #fff8e6;
    border: 1px solid #f0e0a8;
    border-radius: 10px;
    padding: 12px 16px;
    font-size: 0.9rem;
    line-height: 1.6;
}

.msg-2a1b {
    min-height: 24px;
    margin: 12px 0;
    font-weight: 600;
    text-align: center;
}
.msg-2a1b.win-2a1b { color: #2e9e5b; font-size: 1.15rem; }
.msg-2a1b.err-2a1b { color: #d9534f; }

/* 電腦猜題框 */
.cpu-guess-box-2a1b {
    background: #f5f7fa;
    border-radius: 10px;
    padding: 16px;
    margin-top: 14px;
}
.cpu-guess-2a1b {
    font-size: 1.4rem;
    text-align: center;
    margin-bottom: 12px;
}
.cpu-guess-2a1b span {
    font-weight: 700;
    letter-spacing: 8px;
    color: #4a6fa5;
}
.ab-input-2a1b {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    flex-wrap: wrap;
}
.ab-input-2a1b select {
    padding: 6px 8px;
    font-size: 1rem;
    border-radius: 6px;
    border: 2px solid #d0d7de;
}
.candidates-2a1b {
    margin-top: 10px;
    text-align: center;
    font-size: 0.85rem;
    color: #777;
}

/* 歷史紀錄表 */
.history-2a1b {
    width: 100%;
    border-collapse: collapse;
    margin-top: 14px;
    font-size: 0.95rem;
}
.history-2a1b th, .history-2a1b td {
    border-bottom: 1px solid #e5e9ef;
    padding: 8px 6px;
    text-align: center;
}
.history-2a1b th { color: #888; font-weight: 600; }
.history-2a1b td:nth-child(2) { letter-spacing: 4px; font-weight: 600; }
.history-2a1b .res-2a1b { color: #4a6fa5; font-weight: 700; }

/* 排除法整理 */
.analysis-2a1b {
    margin-top: 20px;
    background: #f5f7fa;
    border-radius: 10px;
    padding: 14px 18px;
}
.analysis-2a1b h4 { margin: 0 0 6px; font-size: 1.05rem; }
.analysis-intro-2a1b {
    margin: 0 0 10px;
    font-size: 0.85rem;
    color: #666;
    line-height: 1.6;
}
.analysis-list-2a1b {
    margin: 0;
    padding-left: 22px;
}
.analysis-list-2a1b li {
    margin-bottom: 8px;
    line-height: 1.55;
    font-size: 0.92rem;
}
.analysis-list-2a1b li.bad-2a1b {
    color: #b5482f;
}
.analysis-list-2a1b .flag-2a1b {
    color: #d9534f;
    font-size: 0.85rem;
}
.analysis-list-2a1b .hint-2a1b-row {
    color: #2e6a45;
    font-size: 0.85rem;
}
.analysis-remain-2a1b {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px dashed #d6dde6;
    font-size: 0.92rem;
    color: #2e6a45;
    word-break: break-all;
}