/* ====== 07 方阵问题计算器 · 石版蓝 + 薄荷青方格 ====== */
.tsk.sac{
  --tsk-bg:#f2f5fb;
  --tsk-card:#ffffff;
  --tsk-card-2:#f6f8fd;
  --tsk-ink:#1b2440;
  --tsk-sub:#5a6480;
  --tsk-faint:#8d97ae;
  --tsk-line:#dfe5f1;
  --tsk-line-2:#edf1f9;
  --tsk-brand:#4a5fd0;
  --tsk-brand-2:#6c4bd6;
  --tsk-brand-soft:#e9ecff;
  --tsk-brand-ink:#3b4bb8;
  --tsk-array:#139b8b;
  --tsk-array-soft:#e0f6f2;
  --tsk-gold:#d98a00;
  --tsk-gold-soft:#fdf1d8;
  --tsk-shadow-sm:0 1px 2px rgba(27,36,64,.05),0 7px 16px rgba(27,36,64,.06);
  --tsk-shadow:0 2px 7px rgba(27,36,64,.08),0 20px 44px rgba(27,36,64,.10);
  --tsk-r:14px;
  background:
    linear-gradient(0deg,rgba(19,155,139,.035) 1px,transparent 1px),
    linear-gradient(90deg,rgba(19,155,139,.035) 1px,transparent 1px),
    var(--tsk-bg);
  background-size:26px 26px,26px 26px,auto;
}
:root[data-theme="dark"] .tsk.sac{
  --tsk-bg:#0f131d;
  --tsk-card:#171d2b;
  --tsk-card-2:#1d2433;
  --tsk-ink:#e8ecf7;
  --tsk-sub:#a5afc4;
  --tsk-faint:#78849b;
  --tsk-line:#293348;
  --tsk-line-2:#212a3b;
  --tsk-brand:#8095ff;
  --tsk-brand-2:#a58bff;
  --tsk-brand-soft:rgba(128,149,255,.14);
  --tsk-brand-ink:#9aabff;
  --tsk-array:#4fd8c4;
  --tsk-array-soft:rgba(79,216,196,.12);
  --tsk-gold:#f2b544;
  --tsk-gold-soft:rgba(242,181,68,.13);
}

/* ---- 首屏等高栅格 ---- */
.sac-hero{display:grid;grid-template-columns:minmax(0,1fr) 394px;gap:30px;padding:30px 0 24px;align-items:stretch}
.sac-hero-l{display:flex;flex-direction:column}
.sac-hero-l>.tsk-hs{flex:1 1 auto}
@media (max-width:900px){.sac-hero{grid-template-columns:1fr}}
.sac-hero-l .tsk-h1 b{color:var(--tsk-array)}
.sac-hero-r{display:flex}

/* ---- 方阵沙盘 ---- */
.sac-board{position:relative;width:100%;background:var(--tsk-card);border:1px solid var(--tsk-line);
  border-radius:16px;box-shadow:var(--tsk-shadow);padding:16px 18px 13px;overflow:hidden}
.sac-board::after{content:"";position:absolute;inset:0 auto auto 0;width:132px;height:132px;pointer-events:none;
  background:
    linear-gradient(90deg,var(--tsk-array) 1.5px,transparent 1.5px),
    linear-gradient(0deg,var(--tsk-array) 1.5px,transparent 1.5px);
  background-size:22px 22px;opacity:.10;
  -webkit-mask-image:linear-gradient(135deg,#000,transparent 68%);
  mask-image:linear-gradient(135deg,#000,transparent 68%)}
.sac-board-hd{position:relative;display:flex;align-items:center;gap:10px}
.sac-grid-icon{display:grid;grid-template-columns:repeat(2,7px);gap:3px;flex:none}
.sac-grid-icon i{width:7px;height:7px;border-radius:2px;background:var(--tsk-array)}
.sac-grid-icon i:nth-child(2),.sac-grid-icon i:nth-child(3){background:var(--tsk-array-soft);
  border:1px solid var(--tsk-array)}
.sac-board-hd b{display:block;font-size:14.5px;font-weight:800;line-height:1.3}
.sac-board-hd small{display:block;font-size:11.5px;color:var(--tsk-faint);line-height:1.4}

.sac-tabs{position:relative;display:flex;gap:4px;margin-top:12px;padding:4px;border-radius:9px;
  background:var(--tsk-card-2);border:1px solid var(--tsk-line-2)}
.sac-tab{flex:1;border:0;background:transparent;border-radius:6px;color:var(--tsk-sub);cursor:pointer;
  font:700 11.5px/1.4 var(--tsk-font);padding:8px 2px;transition:.16s;white-space:nowrap}
.sac-tab:hover{color:var(--tsk-brand-ink)}
.sac-tab.on{background:var(--tsk-array);color:#fff;box-shadow:0 4px 11px rgba(19,155,139,.26)}
:root[data-theme="dark"] .sac-tab.on{color:#0f131d}

.sac-panel{padding-top:13px}
.sac-panel.on{animation:sac-fade .22s ease}
@keyframes sac-fade{from{opacity:0;transform:translateY(4px)}to{opacity:1;transform:none}}
.sac-row2{display:grid;grid-template-columns:1fr 1fr;gap:9px}
.sac-field label{display:block;margin-bottom:4px;font-size:11px;font-weight:800;color:var(--tsk-sub);line-height:1.5}
.sac-field input,.sac-field select{width:100%;height:40px;border:1.5px solid var(--tsk-line);border-radius:8px;
  background:var(--tsk-card-2);color:var(--tsk-ink);font:800 14px/40px var(--tsk-num);padding:0 10px;outline:none;
  transition:border-color .15s,box-shadow .15s,background .15s}
.sac-field select{font-family:var(--tsk-font);font-weight:700}
.sac-field input:focus,.sac-field select:focus{border-color:var(--tsk-array);background:var(--tsk-card);
  box-shadow:0 0 0 3px var(--tsk-array-soft)}
.sac-field.bad input,.sac-field.bad select{border-color:var(--tsk-bad);background:var(--tsk-bad-soft)}
.sac-note{margin:10px 0 0;padding:7px 10px;border-radius:6px;background:var(--tsk-card-2);
  border-left:3px solid var(--tsk-array);font-size:10.8px;line-height:1.7;color:var(--tsk-faint)}
.sac-err{display:none;margin:9px 0 0;padding:8px 11px;border-radius:8px;background:var(--tsk-bad-soft);
  color:var(--tsk-bad);font-size:12px;font-weight:700;line-height:1.65}
.sac-err.show{display:block}
.sac-acts{display:flex;gap:7px;margin-top:13px}
.sac-acts .tsk-btn{padding:9px 13px;font-size:12.5px}
.sac-acts .tsk-btn-main{flex:1;border:0;background:linear-gradient(135deg,var(--tsk-array),#0c7f74)}
:root[data-theme="dark"] .sac-acts .tsk-btn-main{color:#0f131d}
.sac-board-foot{margin:10px 0 0;font-size:10.5px;line-height:1.65;color:var(--tsk-faint)}

/* ---- 结果 ---- */
.sac-result{margin:6px 0 28px;background:var(--tsk-card);border:1px solid var(--tsk-line);
  border-radius:16px;box-shadow:var(--tsk-shadow);padding:22px 24px 20px}
.sac-res-hd{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:13px}
.tsk-btn-sm{padding:8px 15px;font-size:12px}
.sac-res-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(158px,1fr));gap:10px}
.sac-res-card{background:var(--tsk-card-2);border:1px solid var(--tsk-line-2);border-radius:11px;padding:15px 17px 13px}
.sac-res-card b{display:block;font:800 26px/1.12 var(--tsk-num);color:var(--tsk-ink);
  font-variant-numeric:tabular-nums;word-break:break-all}
.sac-res-card span{display:block;margin-top:4px;font-size:11.5px;font-weight:800;color:var(--tsk-faint)}
.sac-res-card i{display:block;margin-top:2px;font-style:normal;font-size:10.5px;color:var(--tsk-sub)}
.sac-res-card.sac-main-card{background:var(--tsk-array-soft);border-color:rgba(19,155,139,.26)}
.sac-res-card.sac-main-card b{color:var(--tsk-array)}
.sac-alert{margin-top:12px;padding:10px 13px;border-radius:8px;background:var(--tsk-gold-soft);
  border-left:3px solid var(--tsk-gold);font-size:12.5px;line-height:1.8;color:var(--tsk-sub)}
.sac-alert.is-bad{background:var(--tsk-bad-soft);border-left-color:var(--tsk-bad)}
.sac-alert b{color:var(--tsk-gold)}

/* ---- 点阵图 ---- */
.sac-visual{margin-top:16px;padding:14px 16px 10px;border:1px solid var(--tsk-line);
  border-radius:12px;background:
    radial-gradient(circle at 50% 46%,var(--tsk-array-soft),transparent 62%),var(--tsk-card-2)}
.sac-visual-hd{display:flex;flex-wrap:wrap;align-items:baseline;justify-content:space-between;gap:8px}
.sac-visual-hd span{font-size:11px;font-weight:700;color:var(--tsk-faint)}
.sac-visual svg{display:block;width:100%;max-width:430px;height:auto;margin:6px auto 0}
.sac-visual svg circle{transition:fill .2s}
.sac-visual-note{margin-top:4px;text-align:center;font-size:11px;color:var(--tsk-faint)}

/* ---- 层明细表 ---- */
.sac-table-wrap{margin-top:15px;overflow-x:auto;border-radius:9px;border:1px solid var(--tsk-line)}
.sac-table{width:100%;min-width:420px;border-collapse:collapse;background:var(--tsk-card)}
.sac-table th,.sac-table td{padding:9px 13px;font-size:12.3px;line-height:1.7;text-align:left;
  border-bottom:1px solid var(--tsk-line-2)}
.sac-table thead th{background:var(--tsk-array);color:#fff;font-size:11px;font-weight:800;letter-spacing:.04em}
:root[data-theme="dark"] .sac-table thead th{color:#0f131d}
.sac-table tbody tr:last-child td{border-bottom:0}
.sac-table tbody tr:hover td{background:var(--tsk-card-2)}
.sac-table td:first-child{font-weight:800;color:var(--tsk-ink)}
.sac-table td:nth-child(2),.sac-table td:nth-child(3){font:800 12.5px/1.7 var(--tsk-num);
  color:var(--tsk-brand-ink)}
.sac-table tr.is-hollow td{color:var(--tsk-faint);font-style:italic}

/* ---- 分步推导 ---- */
.sac-steps-wrap{margin-top:16px;padding-top:14px;border-top:1px dashed var(--tsk-line)}
.sac-steps{margin:9px 0 0;padding:0;list-style:none;counter-reset:sacstep;display:grid;gap:6px}
.sac-steps li{counter-increment:sacstep;position:relative;padding:8px 12px 8px 40px;border-radius:7px;
  background:var(--tsk-card-2);border:1px solid var(--tsk-line-2);font-size:12.8px;line-height:1.78;
  color:var(--tsk-sub)}
.sac-steps li::before{content:counter(sacstep);position:absolute;left:10px;top:8px;width:21px;height:21px;
  border-radius:3px;background:var(--tsk-array);color:#fff;font:800 10.5px/21px var(--tsk-num);text-align:center}
.sac-steps li b{color:var(--tsk-ink)}
.sac-sub{margin-left:auto;font-size:11.5px;font-weight:700;color:var(--tsk-faint)}

/* ---- 公式卡 ---- */
.sac-fmls{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:11px}
.sac-fml{position:relative;background:var(--tsk-card);border:1px solid var(--tsk-line);border-radius:11px;
  box-shadow:var(--tsk-shadow-sm);padding:15px 16px;border-top:3px solid var(--tsk-array);overflow:hidden}
.sac-fml:nth-child(2n){border-top-color:var(--tsk-brand)}
.sac-fml:nth-child(3n){border-top-color:var(--tsk-gold)}
.sac-tag{display:inline-block;padding:2px 9px;border-radius:99px;background:var(--tsk-array-soft);
  color:var(--tsk-array);font:800 11px/1.7 var(--tsk-num)}
.sac-fml code{display:block;margin:8px 0;padding:8px 10px;border-radius:6px;background:var(--tsk-card-2);
  color:var(--tsk-brand-ink);font:800 11.5px/1.7 var(--tsk-num);word-break:break-all}
.sac-fml p{margin:0;font-size:12.3px;line-height:1.75;color:var(--tsk-sub)}
.sac-mini{display:grid;grid-template-columns:repeat(3,8px);gap:4px;margin-top:9px}
.sac-mini i{width:8px;height:8px;border-radius:2px;background:var(--tsk-array)}
.sac-mini i:nth-child(5){background:transparent;border:1px solid var(--tsk-array)}

/* ---- 变式练习 ---- */
.sac-var-toolbar{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin-bottom:11px}
.sac-var-tip{font-size:11.5px;color:var(--tsk-faint)}
.sac-variants{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:9px}
.sac-variants .tsk-empty{grid-column:1/-1;background:var(--tsk-card);border:1px dashed var(--tsk-line);
  border-radius:9px}
.sac-var-item{background:var(--tsk-card);border:1px solid var(--tsk-line);border-left:3px solid var(--tsk-array);
  border-radius:9px;padding:12px 14px;box-shadow:var(--tsk-shadow-sm)}
.sac-var-item .no{display:inline-block;margin-right:6px;padding:1px 7px;border-radius:99px;
  background:var(--tsk-array-soft);color:var(--tsk-array);font:800 10.5px/1.8 var(--tsk-num)}
.sac-var-item .q{font-size:12.8px;line-height:1.8;color:var(--tsk-sub)}
.sac-var-item .q b{color:var(--tsk-ink)}
.sac-var-item .ans{margin-top:6px;padding-top:6px;border-top:1px dashed var(--tsk-line-2);
  font-size:12px;line-height:1.7;color:var(--tsk-brand-ink);font-weight:700}
.sac-var-item .ans.is-hidden{display:none}
.sac-var-item .ans b{color:var(--tsk-brand-ink)}

/* ---- 公式自测 ---- */
.sac-quiz{background:var(--tsk-card);border:1px solid var(--tsk-line);border-left:4px solid var(--tsk-array);
  border-radius:11px;box-shadow:var(--tsk-shadow-sm);padding:17px 19px}
.sac-question{margin:0 0 10px;font-size:14px;line-height:1.85;font-weight:700;color:var(--tsk-ink)}
.sac-question b{color:var(--tsk-array)}
.sac-quiz-row{display:flex;flex-wrap:wrap;gap:8px}
.sac-quiz-row input{width:170px;height:39px;padding:0 11px;border:1.5px solid var(--tsk-line);border-radius:8px;
  background:var(--tsk-card-2);color:var(--tsk-ink);font:800 14px/39px var(--tsk-num);outline:none}
.sac-quiz-row input:focus{border-color:var(--tsk-array);box-shadow:0 0 0 3px var(--tsk-array-soft)}
.sac-quiz-fb{margin:8px 0 0;min-height:19px;font-size:12.5px;font-weight:800}
.sac-quiz-fb.ok{color:var(--tsk-array)}
.sac-quiz-fb.no{color:var(--tsk-bad)}

/* ---- 页脚 ---- */
.tsk-foot{margin-top:18px;font-size:11.5px;color:var(--tsk-faint)}

@media (max-width:900px){
  .sac-hero{grid-template-columns:1fr;gap:22px}
  .sac-hero-r{display:block}
}
@media (max-width:600px){
  .sac-row2{grid-template-columns:1fr}
  .sac-res-grid{grid-template-columns:1fr 1fr}
  .sac-acts{flex-wrap:wrap}
  .sac-acts .tsk-btn-main{flex:1 0 100%}
  .sac-quiz-row input{flex:1 0 100%;width:100%}
  .sac-tab{font-size:10.5px}
}

/* ==========================================================
   *  细节打磨：键盘可达性、长数字换行、打印与动效降级
   *  说明：以下规则都限定在 .tsk 工具作用域内，不影响站内其它页面
   * ========================================================== */
.sac .tsk-btn:focus-visible,
.sac .sac-tab:focus-visible,
.sac .sac-seg button:focus-visible{
    outline:2px solid var(--tsk-brand);
    outline-offset:2px;
}
.sac input[type="number"]::-webkit-outer-spin-button,
.sac input[type="number"]::-webkit-inner-spin-button{
    -webkit-appearance:none;
    margin:0;
}
.sac input[type="number"]{
    -moz-appearance:textfield;
    appearance:textfield;
}
.sac input::placeholder,
.sac textarea::placeholder{
    color:var(--tsk-faint);
    opacity:1;
}
.sac ::selection{
    background:var(--tsk-brand-soft);
    color:var(--tsk-brand-ink);
}
.sac .sac-res-card b,
.sac .sac-main-card b{
    font-variant-numeric:tabular-nums lining-nums;
    letter-spacing:-.01em;
    line-height:1.15;
}
.sac .sac-res-card b{
    overflow-wrap:anywhere;
}
.sac .sac-var-item .q,
.sac .sac-question,
.sac .sac-steps li{
    overflow-wrap:break-word;
    word-break:normal;
}
.sac .sac-table-wrap{
    scrollbar-width:thin;
    scrollbar-color:var(--tsk-line) transparent;
}
.sac .sac-table-wrap::-webkit-scrollbar{
    height:8px;
}
.sac .sac-table-wrap::-webkit-scrollbar-thumb{
    background:var(--tsk-line);
    border-radius:99px;
}
.sac .sac-table-wrap::-webkit-scrollbar-track{
    background:transparent;
}
.sac .sac-var-toolbar .tsk-btn,
.sac .sac-acts .tsk-btn,
.sac .sac-quiz-row .tsk-btn{
    touch-action:manipulation;
}
.sac .sac-var-item{
    transition:border-color .15s,box-shadow .15s;
}
.sac .sac-var-item:hover{
    border-color:var(--tsk-brand);
    box-shadow:var(--tsk-shadow-sm);
}
.sac .sac-panel:not(.on){
    display:none;
}
.sac .sac-result[hidden]{
    display:none;
}
.sac .sac-result{
    animation:sac-rise .28s ease both;
}
@keyframes sac-rise{
    from{opacity:0;transform:translateY(8px)}
    to{opacity:1;transform:none}
}
.sac .sac-alert b{
    font-weight:800;
}
.sac .sac-err.show{
    animation:sac-shake .22s ease;
}
@keyframes sac-shake{
    0%,100%{transform:translateX(0)}
    25%{transform:translateX(-3px)}
    75%{transform:translateX(3px)}
}
.sac .tsk-empty{
    padding:18px 16px;
    text-align:center;
    color:var(--tsk-faint);
    font-size:12.5px;
    line-height:1.8;
}
.sac .sac-quiz-row input:disabled,
.sac .sac-acts .tsk-btn:disabled{
    opacity:.55;
    cursor:not-allowed;
}
.sac .sac-res-grid > .sac-res-card:last-child:nth-child(odd){
    grid-column:span 2;
}
@media (max-width:420px){
    .sac .sac-res-grid{
        grid-template-columns:1fr;
    }
    .sac .sac-res-grid > .sac-res-card:last-child:nth-child(odd){
        grid-column:auto;
    }
    .sac .sac-row2,
    .sac .sac-row3{
        grid-template-columns:1fr;
    }
}
@media (prefers-reduced-motion:reduce){
    .sac *,
    .sac *::before,
    .sac *::after{
        animation-duration:.001ms!important;
        animation-iteration-count:1!important;
        transition-duration:.001ms!important;
        scroll-behavior:auto!important;
    }
}
@media print{
    .sac{
        background:#fff!important;
        color:#111!important;
    }
    .sac .tsk-crumb-bar,
    .sac .sac-acts,
    .sac .sac-var-toolbar,
    .sac .sac-quiz,
    .sac .sac-tabs{
        display:none!important;
    }
    .sac .sac-result{
        box-shadow:none!important;
        border:1px solid #ddd!important;
        animation:none!important;
    }
    .sac .sac-res-grid{
        grid-template-columns:repeat(2,minmax(0,1fr))!important;
    }
    .sac .sac-var-item{
        break-inside:avoid;
    }
    .sac .sac-table{
        font-size:11px!important;
    }
}