/* ======================================================================
 *  错题本管理器 /tool/mistake-book
 *  依赖 calc-common.css 变量与公共类，支持黑夜模式与打印。
 * ====================================================================== */

.mb-seg {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    margin-bottom: 16px;
}
.mb-seg button {
    height: 42px;
    border-radius: 12px;
    border: 1px solid var(--c-border);
    background: var(--c-surface-soft);
    color: var(--c-text-sub);
    font-family: inherit;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.16s ease;
    white-space: nowrap;
    padding: 0 6px;
}
.mb-seg button:hover { border-color: #7c5cff; color: #7c5cff; }
.mb-seg button.is-active {
    background: linear-gradient(135deg, rgba(124, 92, 255, 0.16), rgba(124, 92, 255, 0.07));
    border-color: rgba(124, 92, 255, 0.55);
    color: #6a4ae0;
}
.mb-badge {
    display: inline-block;
    min-width: 18px;
    height: 18px;
    line-height: 18px;
    padding: 0 5px;
    margin-left: 3px;
    border-radius: 99px;
    background: rgba(124, 92, 255, 0.15);
    color: #6a4ae0;
    font-size: 11px;
    font-weight: 800;
}
.mb-badge--hot { background: #ff5a4e; color: #fff; }

/* ---------- 筛选条 ---------- */
.mb-filter {
    display: flex;
    gap: 8px;
    margin-bottom: 14px;
    flex-wrap: wrap;
}
.mb-filter .calc-input { width: auto; flex: 1 1 130px; height: 38px; font-size: 13px; }
.mb-export {
    height: 38px;
    padding: 0 12px;
    font-size: 12.5px;
    display: inline-flex;
    align-items: center;
    cursor: pointer;
}

/* ---------- 错题卡片 ---------- */
.mb-list { display: grid; gap: 10px; max-height: 620px; overflow-y: auto; padding-right: 4px; }
.mb-item {
    border: 1px solid var(--c-border);
    border-radius: 14px;
    padding: 13px 14px;
    background: var(--c-surface-soft);
    transition: border-color 0.16s ease, box-shadow 0.16s ease;
}
.mb-item:hover { border-color: rgba(124, 92, 255, 0.45); box-shadow: var(--shadow-sm); }
.mb-item-head { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; margin-bottom: 8px; }
.mb-subj {
    padding: 2px 10px;
    border-radius: 99px;
    font-size: 11.5px;
    font-weight: 800;
    color: #fff;
}
.mb-subj--语文 { background: #e0447c; }
.mb-subj--数学 { background: #0a7fc0; }
.mb-subj--英语 { background: #7c5cff; }
.mb-subj--科学 { background: #0e9f6e; }
.mb-subj--其他 { background: #8a93a8; }
.mb-cause-tag {
    padding: 2px 9px;
    border-radius: 99px;
    background: rgba(255, 138, 61, 0.14);
    color: #c75d10;
    font-size: 11.5px;
    font-weight: 700;
}
.mb-diff { font-size: 11px; letter-spacing: 1px; }
.mb-date { margin-left: auto; font-size: 11.5px; color: var(--c-text-muted); }
.mb-item-title { font-size: 14px; font-weight: 700; color: var(--c-text); line-height: 1.6; margin-bottom: 7px; }
.mb-item-row { display: flex; gap: 8px; font-size: 13px; line-height: 1.7; align-items: baseline; }
.mb-k { flex: none; width: 34px; color: var(--c-text-muted); font-size: 12px; }
.mb-wrong { color: #e0342b; text-decoration: line-through; text-decoration-color: rgba(224,52,43,.5); word-break: break-all; }
.mb-rightans { color: #1f9d43; font-weight: 700; word-break: break-all; }
.mb-item-note {
    margin-top: 7px;
    padding: 8px 10px;
    border-radius: 9px;
    background: rgba(124, 92, 255, 0.07);
    border-left: 3px solid #7c5cff;
    font-size: 12.5px;
    line-height: 1.7;
    color: var(--c-text-sub);
}
.mb-item-foot { display: flex; align-items: center; gap: 8px; margin-top: 10px; flex-wrap: wrap; }
.mb-tag { font-size: 11.5px; font-weight: 700; padding: 3px 10px; border-radius: 99px; }
.mb-tag--due { background: rgba(255, 176, 32, 0.14); color: #b97600; }
.mb-tag--done { background: rgba(52, 199, 89, 0.12); color: #1f9d43; }
.mb-card-btn { height: 32px; padding: 0 12px; font-size: 12.5px; }
.mb-del {
    margin-left: auto;
    border: none;
    background: none;
    cursor: pointer;
    font-size: 15px;
    padding: 4px 6px;
    border-radius: 8px;
    opacity: .55;
    transition: opacity 0.15s ease, background 0.15s ease;
}
.mb-del:hover { opacity: 1; background: rgba(255, 59, 48, 0.1); }
.mb-empty {
    padding: 44px 20px;
    text-align: center;
    font-size: 13.5px;
    color: var(--c-text-muted);
    line-height: 1.9;
    border: 1.5px dashed var(--c-border);
    border-radius: 14px;
}

/* ---------- 录入表单 ---------- */
.mb-cause-pick, .mb-diff-pick { display: flex; flex-wrap: wrap; gap: 8px; }
.mb-cause-pick button, .mb-diff-pick button {
    padding: 7px 13px;
    border-radius: 99px;
    border: 1.5px solid var(--c-border);
    background: var(--c-surface-soft);
    color: var(--c-text-sub);
    font-family: inherit;
    font-size: 12.5px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.15s ease;
}
.mb-cause-pick button:hover { border-color: #7c5cff; color: #7c5cff; }
.mb-cause-pick button.is-active { background: rgba(124, 92, 255, 0.13); border-color: #7c5cff; color: #6a4ae0; }
.mb-diff-pick button.is-active { background: rgba(255, 176, 32, 0.14); border-color: #ffb020; color: #b97600; }
.mb-textarea {
    width: 100%;
    padding: 11px 13px;
    border-radius: 12px;
    border: 1px solid var(--c-border);
    background: var(--c-surface-soft);
    color: var(--c-text);
    font-family: inherit;
    font-size: 13.5px;
    line-height: 1.7;
    resize: vertical;
    outline: none;
}
.mb-textarea:focus { border-color: var(--c-primary); box-shadow: 0 0 0 3px var(--c-primary-soft); }
.mb-msg-ok { color: #1f9d43; font-weight: 700; margin-top: 8px; }
.mb-msg-err { color: #e0342b; font-weight: 700; margin-top: 8px; }

/* ---------- 复习提示 ---------- */
.mb-review-tip {
    padding: 13px 15px;
    border-radius: 12px;
    background: linear-gradient(135deg, rgba(124, 92, 255, 0.08), rgba(0, 150, 220, 0.05));
    border: 1px solid rgba(124, 92, 255, 0.28);
    font-size: 13px;
    line-height: 1.85;
    color: var(--c-text-sub);
    margin-bottom: 14px;
}
.mb-review-tip b { color: var(--c-text); }

/* ---------- 右侧统计 ---------- */
.mb-detail-tag {
    display: inline-block;
    padding: 3px 14px;
    border-radius: 99px;
    background: rgba(124, 92, 255, 0.13);
    color: #6a4ae0;
    font-size: 12px;
    font-weight: 800;
    margin-bottom: 12px;
}
.mb-barfill { background: linear-gradient(90deg, #7c5cff, #a78bff); }
.mb-ai-zone { margin-top: 16px; border-top: 1px dashed var(--c-border); padding-top: 6px; }
.mb-ai-p { font-size: 13px; line-height: 1.8; color: var(--c-text); margin: 6px 0 12px; }
.mb-ai-answer {
    padding: 10px 12px;
    border-radius: 10px;
    background: rgba(52, 199, 89, 0.08);
    border: 1px solid rgba(52, 199, 89, 0.3);
    color: #1f9d43;
    font-weight: 700;
}

/* ---------- 响应式 ---------- */
@media (max-width: 640px) {
    .mb-seg { grid-template-columns: 1fr; }
    .mb-filter .calc-input { flex-basis: calc(50% - 8px); }
    .mb-date { margin-left: 0; }
}

/* ---------- 黑夜模式 ---------- */
[data-theme="dark"] .mb-seg button { background: rgba(255, 255, 255, 0.04); }
[data-theme="dark"] .mb-seg button.is-active { background: rgba(124, 92, 255, 0.2); border-color: rgba(124, 92, 255, 0.55); color: #a78bff; }
[data-theme="dark"] .mb-badge { background: rgba(124, 92, 255, 0.25); color: #a78bff; }
[data-theme="dark"] .mb-badge--hot { background: #ff5a4e; color: #fff; }
[data-theme="dark"] .mb-cause-tag { background: rgba(255, 138, 61, 0.18); color: #ffb84d; }
[data-theme="dark"] .mb-cause-pick button,
[data-theme="dark"] .mb-diff-pick button { background: rgba(255, 255, 255, 0.04); }
[data-theme="dark"] .mb-cause-pick button.is-active { background: rgba(124, 92, 255, 0.22); border-color: #a78bff; color: #a78bff; }
[data-theme="dark"] .mb-diff-pick button.is-active { background: rgba(255, 176, 32, 0.18); border-color: #ffb020; color: #ffb84d; }
[data-theme="dark"] .mb-tag--due { background: rgba(255, 176, 32, 0.16); color: #ffb84d; }
[data-theme="dark"] .mb-tag--done { background: rgba(52, 199, 89, 0.16); color: #4ede78; }
[data-theme="dark"] .mb-item-note { background: rgba(124, 92, 255, 0.12); }
[data-theme="dark"] .mb-review-tip { background: rgba(124, 92, 255, 0.1); border-color: rgba(124, 92, 255, 0.3); }
[data-theme="dark"] .mb-detail-tag { background: rgba(124, 92, 255, 0.2); color: #a78bff; }
[data-theme="dark"] .mb-ai-answer { background: rgba(52, 199, 89, 0.13); color: #4ede78; }
[data-theme="dark"] .mb-textarea { background: rgba(255, 255, 255, 0.04); }
[data-theme="dark"] .mb-wrong { color: #ff9a94; }
[data-theme="dark"] .mb-rightans { color: #4ede78; }