/*!
 * 数学公式查询 —— 工具样式（按年级 / 分类查询，含例题）
 * 与站点其它工具页保持一致，并完整适配黑夜模式。
 */

.mf-wrap { max-width: 100%; }

/* ---------------- 工具条 ---------------- */
.mf-toolbar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
    padding: 14px 16px;
    border: 1px solid var(--c-border, #eef1f6);
    border-radius: 16px;
    background: var(--c-bg-card, #fff);
    margin-bottom: 10px;
}

.mf-search {
    position: relative;
    flex: 1 1 240px;
    min-width: 200px;
}

.mf-search input {
    width: 100%;
    height: 38px;
    padding: 0 12px 0 34px;
    font-size: 14px;
    color: var(--c-text, #0f172a);
    border: 1px solid var(--c-border, #e2e8f0);
    border-radius: 10px;
    background: var(--c-surface-soft, #f7f9fc);
    outline: none;
    transition: border-color .15s, box-shadow .15s;
}

.mf-search input:focus {
    border-color: var(--c-primary, #0066ff);
    box-shadow: 0 0 0 3px rgba(0, 102, 255, .12);
}

.mf-search .ico {
    position: absolute;
    left: 11px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 14px;
    opacity: .6;
    pointer-events: none;
}

.mf-tabs {
    display: inline-flex;
    flex-wrap: wrap;
    gap: 6px;
    padding: 3px;
    border-radius: 10px;
    background: var(--c-surface-soft, #f1f5f9);
    border: 1px solid var(--c-border, #e2e8f0);
}

.mf-tabs button {
    padding: 6px 13px;
    font-size: 13px;
    font-weight: 600;
    color: var(--c-text-sub, #475569);
    background: transparent;
    border: 0;
    border-radius: 8px;
    cursor: pointer;
    transition: all .15s;
}

.mf-tabs button.is-active { color: #fff; background: var(--c-primary, #0066ff); }

.mf-btn {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    height: 38px;
    padding: 0 13px;
    font-size: 13px;
    font-weight: 600;
    color: var(--c-text-sub, #475569);
    background: var(--c-surface-soft, #f1f5f9);
    border: 1px solid var(--c-border, #e2e8f0);
    border-radius: 10px;
    cursor: pointer;
    transition: all .15s;
}

.mf-btn:hover { border-color: var(--c-primary, #0066ff); color: var(--c-primary, #0066ff); }
.mf-btn.is-active { color: #fff; background: #f59f00; border-color: #f59f00; }

.mf-meta {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-left: auto;
    font-size: 12.5px;
    color: var(--c-text-muted, #94a3b8);
}

.mf-meta b { color: var(--c-primary, #0066ff); font-variant-numeric: tabular-nums; }

/* 分类筛选条 */
.mf-catbar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 7px;
    margin-bottom: 14px;
}

.mf-catbar-label {
    font-size: 12.5px;
    font-weight: 700;
    color: var(--c-text-muted, #94a3b8);
}

.mf-chip {
    padding: 5px 12px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--c-text-sub, #475569);
    background: var(--c-bg-card, #fff);
    border: 1px solid var(--c-border, #e2e8f0);
    border-radius: 999px;
    cursor: pointer;
    transition: all .15s;
}

.mf-chip:hover { border-color: var(--c-primary, #0066ff); color: var(--c-primary, #0066ff); }

.mf-chip.is-active {
    color: #fff;
    background: var(--c-primary, #0066ff);
    border-color: var(--c-primary, #0066ff);
}

/* ---------------- 分区 ---------------- */
.mf-sec { margin-bottom: 24px; }

.mf-sec-t {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 0 0 14px;
    padding-left: 10px;
    font-size: 17px;
    font-weight: 800;
    color: var(--c1, #0066ff);
    border-left: 4px solid var(--c1, #0066ff);
}

.mf-sec-icon { font-size: 18px; }

.mf-sec-t em, .mf-cat-t em {
    margin-left: 2px;
    padding: 1px 8px;
    font-size: 11.5px;
    font-style: normal;
    font-weight: 700;
    color: var(--c-text-muted, #94a3b8);
    background: var(--c-surface-soft, #f1f5f9);
    border-radius: 999px;
}

.mf-cat { margin-bottom: 16px; }

.mf-cat-t {
    display: flex;
    align-items: center;
    gap: 6px;
    margin: 0 0 8px;
    font-size: 13.5px;
    font-weight: 800;
    color: var(--c-text-sub, #475569);
}

.mf-cat-t::before {
    content: '';
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--c-text-muted, #94a3b8);
}

.mf-items { display: flex; flex-direction: column; gap: 8px; }

/* ---------------- 公式卡片 ---------------- */
.mf-item {
    position: relative;
    border: 1px solid var(--c-border, #eef1f6);
    border-radius: 12px;
    background: var(--c-bg-card, #fff);
    transition: border-color .15s, box-shadow .15s;
}

.mf-item:hover { border-color: rgba(0, 102, 255, .35); }
.mf-item.is-open { border-color: var(--c-primary, #0066ff); box-shadow: 0 6px 20px rgba(0, 0, 0, .06); }

.mf-head {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 11px 46px 11px 13px;
    text-align: left;
    background: transparent;
    border: 0;
    border-radius: 12px;
    cursor: pointer;
    font-family: inherit;
}

.mf-grade {
    flex: 0 0 auto;
    padding: 2px 9px;
    font-size: 11px;
    font-weight: 700;
    color: #fff;
    background: var(--c1, #0066ff);
    border-radius: 6px;
}

.mf-name {
    flex: 0 0 auto;
    max-width: 34%;
    font-size: 14.5px;
    font-weight: 700;
    color: var(--c-text, #0f172a);
}

.mf-quick {
    flex: 1 1 auto;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-size: 14px;
    color: var(--c-text-sub, #475569);
    font-family: "Cambria Math", "Times New Roman", Georgia, serif;
}

.mf-arrow {
    flex: 0 0 auto;
    margin-left: auto;
    font-size: 12px;
    color: var(--c-text-muted, #94a3b8);
    transition: transform .18s;
}

.mf-item.is-open .mf-arrow { transform: rotate(180deg); }

.mf-star {
    position: absolute;
    top: 8px;
    right: 10px;
    width: 28px;
    height: 28px;
    font-size: 16px;
    line-height: 1;
    color: var(--c-text-muted, #94a3b8);
    background: transparent;
    border: 0;
    border-radius: 8px;
    cursor: pointer;
    transition: color .15s, transform .15s;
}

.mf-star:hover { transform: scale(1.15); }
.mf-star.is-on { color: #f59f00; }

/* 展开区 */
.mf-body {
    display: none;
    padding: 0 14px 14px;
    border-top: 1px dashed var(--c-border, #eef1f6);
}

.mf-item.is-open .mf-body { display: block; }

.mf-formula {
    margin: 14px 0;
    padding: 14px 16px;
    font-size: 19px;
    line-height: 1.95;
    text-align: center;
    color: var(--c-text, #0f172a);
    background: var(--c-surface-soft, #f7f9fc);
    border-radius: 10px;
    font-family: "Cambria Math", "Times New Roman", Georgia, serif;
    overflow-x: auto;
}

.mf-formula i { font-style: italic; }
.mf-formula sub { font-size: .68em; }
.mf-formula sup { font-size: .68em; }

.mf-block { margin-bottom: 13px; }

.mf-block-t {
    margin-bottom: 7px;
    font-size: 12px;
    font-weight: 700;
    color: var(--c-text-muted, #94a3b8);
}

.mf-vars { width: 100%; border-collapse: collapse; font-size: 13px; }

.mf-vars th {
    padding: 6px 10px;
    text-align: left;
    font-size: 11.5px;
    font-weight: 700;
    color: var(--c-text-muted, #94a3b8);
    background: var(--c-surface-soft, #f7f9fc);
}

.mf-vars td {
    padding: 7px 10px;
    border-bottom: 1px solid var(--c-border, #eef1f6);
    color: var(--c-text-sub, #475569);
    vertical-align: top;
}

.mf-vars tbody tr:last-child td { border-bottom: 0; }

.mf-var {
    width: 96px;
    font-family: "Cambria Math", "Times New Roman", Georgia, serif;
    font-size: 15px;
    color: var(--c-text, #0f172a) !important;
}

/* 例题 */
.mf-ex {
    margin-bottom: 13px;
    padding: 13px 15px;
    border: 1px solid var(--c-border, #eef1f6);
    border-radius: 10px;
}

.mf-ex-t {
    margin-bottom: 8px;
    font-size: 12.5px;
    font-weight: 800;
    color: var(--c-primary, #0066ff);
}

.mf-ex-q {
    margin-bottom: 10px;
    font-size: 14px;
    line-height: 1.8;
    color: var(--c-text, #0f172a);
}

.mf-ex-steps { margin: 0 0 10px; padding-left: 20px; }

.mf-ex-steps li {
    margin-bottom: 5px;
    font-size: 13.5px;
    line-height: 1.85;
    color: var(--c-text-sub, #475569);
}

.mf-ex-r {
    display: flex;
    align-items: baseline;
    gap: 8px;
    padding-top: 9px;
    border-top: 1px dashed var(--c-border, #eef1f6);
    font-size: 13.5px;
}

.mf-ex-r span {
    flex: 0 0 auto;
    padding: 1px 8px;
    font-size: 11.5px;
    font-weight: 700;
    color: #2b8a3e;
    background: rgba(47, 158, 68, .12);
    border-radius: 5px;
}

.mf-ex-r b {
    font-size: 14.5px;
    color: var(--c-text, #0f172a);
    font-family: "Cambria Math", "Times New Roman", Georgia, serif;
}

.mf-note {
    padding: 11px 13px;
    font-size: 13px;
    line-height: 1.8;
    color: var(--c-text-sub, #475569);
    background: rgba(0, 102, 255, .05);
    border-left: 3px solid var(--c-primary, #0066ff);
    border-radius: 0 8px 8px 0;
}

.mf-note b { display: block; margin-bottom: 3px; color: var(--c-text, #0f172a); }

.mf-body-actions { margin-top: 12px; }

.mf-copy {
    padding: 6px 13px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--c-primary, #0066ff);
    background: transparent;
    border: 1px solid rgba(0, 102, 255, .35);
    border-radius: 8px;
    cursor: pointer;
    transition: all .15s;
}

.mf-copy:hover { color: #fff; background: var(--c-primary, #0066ff); }

/* ---------------- 空状态 ---------------- */
.mf-empty {
    padding: 46px 16px;
    text-align: center;
    border: 1px dashed var(--c-border, #dbe3ef);
    border-radius: 14px;
    color: var(--c-text-muted, #94a3b8);
}

.mf-empty .emoji { font-size: 38px; margin-bottom: 10px; }
.mf-empty p { font-size: 13.5px; line-height: 1.7; }

/* ---------------- 轻提示 ---------------- */
.mf-toast {
    position: fixed;
    left: 50%;
    bottom: 40px;
    transform: translate(-50%, 16px);
    padding: 10px 20px;
    font-size: 13.5px;
    font-weight: 600;
    color: #fff;
    background: rgba(15, 23, 42, .92);
    border-radius: 999px;
    opacity: 0;
    pointer-events: none;
    transition: opacity .2s, transform .2s;
    z-index: 999;
}

.mf-toast.is-show { opacity: 1; transform: translate(-50%, 0); }

/* ---------------- 响应式 ---------------- */
@media (max-width: 640px) {
    .mf-toolbar { padding: 12px; }
    .mf-meta { margin-left: 0; }
    .mf-head { flex-wrap: wrap; padding-right: 44px; }
    .mf-name { max-width: 100%; }
    .mf-quick { flex-basis: 100%; width: 100%; font-size: 13px; }
    .mf-formula { font-size: 16px; padding: 12px; }
    .mf-vars { font-size: 12px; }
    .mf-var { width: 76px; }
}

/* ---------------- 黑夜模式 ---------------- */
[data-theme="dark"] .mf-toolbar,
[data-theme="dark"] .mf-item {
    background: var(--c-bg-card, #131c31);
    border-color: rgba(255, 255, 255, .08);
}

[data-theme="dark"] .mf-search input {
    background: rgba(255, 255, 255, .04);
    border-color: rgba(255, 255, 255, .12);
    color: var(--c-text, #e5e7eb);
}

[data-theme="dark"] .mf-tabs { background: rgba(255, 255, 255, .04); border-color: rgba(255, 255, 255, .1); }
[data-theme="dark"] .mf-tabs button { color: var(--c-text-sub, #9ca3af); }
[data-theme="dark"] .mf-tabs button.is-active { color: #fff; }

[data-theme="dark"] .mf-btn,
[data-theme="dark"] .mf-chip {
    color: var(--c-text-sub, #9ca3af);
    background: rgba(255, 255, 255, .04);
    border-color: rgba(255, 255, 255, .12);
}

[data-theme="dark"] .mf-btn:hover,
[data-theme="dark"] .mf-chip:hover { color: #58bdf0; border-color: #58bdf0; }

[data-theme="dark"] .mf-btn.is-active,
[data-theme="dark"] .mf-chip.is-active { color: #fff; }

[data-theme="dark"] .mf-sec-t em,
[data-theme="dark"] .mf-cat-t em { background: rgba(255, 255, 255, .06); }

[data-theme="dark"] .mf-item:hover { border-color: rgba(88, 189, 240, .5); }

[data-theme="dark"] .mf-item.is-open {
    border-color: #58bdf0;
    box-shadow: 0 6px 20px rgba(0, 0, 0, .4);
}

[data-theme="dark"] .mf-formula,
[data-theme="dark"] .mf-vars th { background: rgba(255, 255, 255, .04); }

[data-theme="dark"] .mf-ex { border-color: rgba(255, 255, 255, .1); }
[data-theme="dark"] .mf-ex-t { color: #58bdf0; }
[data-theme="dark"] .mf-ex-r span { color: #4ede78; background: rgba(52, 222, 120, .14); }

[data-theme="dark"] .mf-note { background: rgba(88, 189, 240, .1); border-left-color: #58bdf0; }

[data-theme="dark"] .mf-copy { color: #58bdf0; border-color: rgba(88, 189, 240, .45); }
[data-theme="dark"] .mf-copy:hover { color: #04121f; background: #58bdf0; }

[data-theme="dark"] .mf-empty { border-color: rgba(255, 255, 255, .16); }