/* ============================================================
   数学学科页 · 学习流程图 .mth-flow（2026-10-12 首版 · 先数学）
   母题承 .mth-*：草稿纸网格 + 数轴进程线（一条从左到右推进的轴）
   命名空间 .mth-flow / .mf-*，只作用于数学页，不污染其他学科
   配色语义：灰(还不知道) → 墨蓝(在学) → 紫(在练) → 橙(有坑) → 青(记住) → 绿(考过)
   深浅色：浅色为主 + html[data-theme="dark"] 覆盖（不写死色，跟 --ink/--surface）
   ============================================================ */

/* ---- 容器：白底细描边（与数学卡同语言） + 草稿纸网格 ---- */
.mth-flow{position:relative;overflow:hidden;border-radius:20px;margin:0 0 16px;padding:18px 22px 16px;
  background:#fff;border:1px solid #e3eaf8;
  box-shadow:0 14px 34px -26px rgba(63,86,196,.42)}
.mth-flow::before{content:'';position:absolute;inset:0;pointer-events:none;
  background-image:
    linear-gradient(rgba(63,86,196,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(63,86,196,.05) 1px,transparent 1px);
  background-size:26px 26px;
  -webkit-mask-image:radial-gradient(130% 140% at 100% 0%,#000 26%,transparent 94%);
  mask-image:radial-gradient(130% 140% at 100% 0%,#000 26%,transparent 94%)}
.mth-flow > *{position:relative;z-index:2}

/* ---- 头部：标题 + 副标 + 三个真源徽标 ---- */
.mth-flow-head{display:flex;align-items:flex-end;gap:14px;flex-wrap:wrap}
.mth-flow-hl{min-width:0;flex:1 1 320px}
.mth-flow-title{margin:0;font-size:19px;font-weight:800;letter-spacing:-.2px;color:#132038;
  display:flex;align-items:center;gap:8px}
.mth-flow-title .mf-em{background:linear-gradient(120deg,#3f56c4 0%,#2563EB 50%,#0FA5A5 100%);
  -webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;color:transparent}
.mth-flow-title .mf-ax{display:inline-flex;align-items:center;justify-content:center;
  padding:3px 9px;border-radius:999px;font-size:11px;font-weight:700;letter-spacing:.3px;
  color:#3f56c4;background:rgba(63,86,196,.09);border:1px solid rgba(63,86,196,.2)}
.mth-flow-sub{margin:7px 0 0;font-size:13px;line-height:1.75;color:#78829c;max-width:640px}
.mth-flow-metrics{display:flex;gap:9px;flex:0 0 auto}
.mf-metric{min-width:76px;padding:7px 12px;border-radius:12px;text-align:center;
  background:#f6f8ff;border:1px solid #e6ecfa}
.mf-metric b{display:block;font-size:19px;font-weight:800;line-height:1.25;color:#132038;
  font-variant-numeric:tabular-nums}
.mf-metric span{display:block;margin-top:2px;font-size:11.5px;color:#78829c}

/* ---- 六环主轴 ---- */
.mth-flow-axis{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,104px),1fr));
  gap:10px;margin-top:16px}
.mf-node{--nbg:#fbfcff;position:relative;display:flex;flex-direction:column;align-items:flex-start;
  padding:11px 10px 10px;border-radius:14px;text-decoration:none;color:inherit;
  background:var(--nbg);border:1px solid #e8edf8;min-height:150px;
  transition:transform .16s ease,box-shadow .16s ease,border-color .16s ease}
.mf-node:hover,.mf-node:focus-visible{transform:translateY(-3px);--nbg:#fff;border-color:var(--c);
  box-shadow:0 13px 26px -16px rgba(63,86,196,.55);outline:none}
/* 轴线段：每个节点自带一段，首尾各取一半 —— 换行时每行仍自成一条轴，不会断成孤立圆点 */
.mf-track{position:absolute;top:26px;left:0;right:0;height:2px;pointer-events:none;z-index:0;
  background:linear-gradient(90deg,#64748B 0%,#3f56c4 24%,#6D5EFC 44%,#FF6B35 64%,#0FA5A5 82%,#1F9D6B 100%);
  opacity:.32}
.mf-node:first-child .mf-track{left:50%}
.mf-node:last-child .mf-track{right:50%}
.mf-dot{position:relative;z-index:2;flex:0 0 auto;width:32px;height:32px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  font-size:14.5px;font-weight:800;color:var(--c);background:var(--nbg);border:2px solid var(--c);
  box-shadow:0 0 0 4px var(--nbg);
  transition:background .16s ease,box-shadow .16s ease}
.mf-node:hover .mf-dot{background:#fff}
.mf-name{position:relative;z-index:2;margin-top:10px;font-size:15px;font-weight:800;color:#132038;
  letter-spacing:-.1px}
.mf-what{margin-top:3px;font-size:11px;font-weight:700;color:var(--c);letter-spacing:.1px}
.mf-desc{margin-top:6px;font-size:12px;line-height:1.65;color:#6b7590}
.mf-go{margin-top:auto;padding-top:9px;font-size:12.5px;font-weight:800;color:var(--c);
  display:inline-flex;align-items:center;gap:4px}
.mf-go::after{content:'';width:13px;height:13px;background:currentColor;
  -webkit-mask:no-repeat center/contain url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12h14M13 5l7 7-7 7'/%3E%3C/svg%3E");
  mask:no-repeat center/contain url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12h14M13 5l7 7-7 7'/%3E%3C/svg%3E")}
.mf-alt{margin-top:7px;font-size:11.5px;color:#9099ad;cursor:pointer;
  border-bottom:1px dotted #c8cfe2;transition:color .15s ease,border-color .15s ease}
.mf-alt:hover,.mf-alt:focus-visible{color:var(--c);border-color:var(--c);outline:none}

/* ---- 底部：看结果 · 找同伴（芯片行，弱化于六环） ---- */
.mth-flow-foot{display:flex;align-items:center;gap:5px;flex-wrap:wrap;
  margin-top:14px;padding-top:12px;border-top:1px dashed #e3e9f7}
.mf-foot-lab{flex:0 0 auto;font-size:11px;font-weight:700;color:#9aa2b6;letter-spacing:0}
.mf-chip{display:inline-flex;align-items:center;gap:4px;padding:4px 8px;border-radius:999px;
  font-size:11.5px;font-weight:700;color:#4d5878;text-decoration:none;
  background:#f6f8ff;border:1px solid #e6ecfa;
  transition:background .15s ease,color .15s ease,border-color .15s ease,transform .15s ease}
.mf-chip:hover{background:#3f56c4;color:#fff;border-color:transparent;transform:translateY(-1px)}
.mf-sep{flex:0 0 auto;width:1px;height:15px;background:#e3e9f7;margin:0 3px}

/* ---- 窄屏：徽标换行、节点放宽（112px 在手机上太挤） ---- */
@media (max-width:900px){
  .mth-flow{padding:16px 15px 14px}
  .mth-flow-metrics{flex-wrap:wrap}
  .mth-flow-axis{grid-template-columns:repeat(auto-fit,minmax(min(100%,150px),1fr))}
}

/* ============================================================
   深色：夜航草稿纸（网格留、轴留、纸换深蓝）
   ============================================================ */
html[data-theme="dark"] .mth-flow{
  background:var(--surface,#1E1B2E);border-color:var(--hair-strong,rgba(255,255,255,.14));
  box-shadow:0 14px 34px -26px rgba(0,0,0,.66)}
html[data-theme="dark"] .mth-flow::before{
  background-image:linear-gradient(rgba(155,140,255,.09) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(155,140,255,.09) 1px,transparent 1px)}
html[data-theme="dark"] .mth-flow-title{color:var(--ink,#fff)}
html[data-theme="dark"] .mth-flow-title .mf-ax{color:#C9BEFF;background:rgba(155,140,255,.14);
  border-color:rgba(155,140,255,.32)}
html[data-theme="dark"] .mth-flow-sub{color:var(--ink-3)}
html[data-theme="dark"] .mf-metric{background:rgba(255,255,255,.05);
  border-color:var(--hair-strong,rgba(255,255,255,.13))}
html[data-theme="dark"] .mf-metric b{color:var(--ink,#fff)}
html[data-theme="dark"] .mf-metric span{color:var(--ink-3)}
html[data-theme="dark"] .mf-node{--nbg:rgba(255,255,255,.035);border-color:var(--hair-strong,rgba(255,255,255,.13))}
html[data-theme="dark"] .mf-node:hover,.mf-node:focus-visible{--nbg:rgba(255,255,255,.07)}
html[data-theme="dark"] .mf-dot{background:var(--surface,#1E1B2E)}
html[data-theme="dark"] .mf-node:hover .mf-dot{background:var(--surface,#1E1B2E)}
html[data-theme="dark"] .mf-name{color:var(--ink,#fff)}
html[data-theme="dark"] .mf-desc{color:var(--ink-3)}
html[data-theme="dark"] .mf-alt{color:var(--ink-3);border-color:rgba(255,255,255,.18)}
html[data-theme="dark"] .mth-flow-foot{border-top-color:var(--hair-strong,rgba(255,255,255,.13))}
html[data-theme="dark"] .mf-foot-lab{color:var(--ink-3)}
html[data-theme="dark"] .mf-chip{color:var(--ink-2);background:rgba(255,255,255,.05);
  border-color:var(--hair-strong,rgba(255,255,255,.13))}
html[data-theme="dark"] .mf-chip:hover{background:#6D5EFC;color:#fff;border-color:transparent}
html[data-theme="dark"] .mf-sep{background:var(--hair-strong,rgba(255,255,255,.13))}

/* ============================================================
   v2（2026-10-12）：每环配套功能按钮列 + 上下左右拖拽自定义
   每列第 1 个按钮 = 该环主按钮（实心主色 + 箭头）；徽标=真源数字
   ============================================================ */
.mf-btns{display:flex;flex-direction:column;gap:6px;width:100%;margin-top:10px}
.mf-btn{position:relative;z-index:2;display:flex;align-items:center;justify-content:space-between;gap:5px;
  width:100%;padding:7px 9px;border-radius:9px;font-size:12px;font-weight:700;text-decoration:none;color:#3d465e;
  background:#f4f7fe;border:1px solid #e6ecfa;cursor:grab;font-family:inherit;line-height:1.4;text-align:left;
  transition:background .15s ease,color .15s ease,border-color .15s ease,box-shadow .15s ease,transform .15s ease}
.mf-btn:hover{background:#fff;border-color:var(--c);color:var(--c);transform:translateY(-1px)}
.mf-btn:active{cursor:grabbing}
.mf-btn-main{color:#fff;background:var(--c);border-color:transparent;box-shadow:0 8px 16px -9px var(--c)}
.mf-btn-main:hover{background:var(--c);color:#fff;filter:brightness(1.07);transform:translateY(-1px)}
.mf-btn-main::after{content:'';flex:0 0 auto;width:11px;height:11px;background:currentColor;opacity:.9;
  -webkit-mask:no-repeat center/contain url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='2.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12h14M13 5l7 7-7 7'/%3E%3C/svg%3E");
  mask:no-repeat center/contain url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='2.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12h14M13 5l7 7-7 7'/%3E%3C/svg%3E")}
.mf-badge{position:absolute;top:-7px;right:5px;z-index:3;font-style:normal;font-size:10px;font-weight:800;
  line-height:1;padding:3px 6px;border-radius:999px;background:#fff;color:var(--c);white-space:nowrap;
  border:1px solid var(--c);font-variant-numeric:tabular-nums;box-shadow:0 2px 6px -3px rgba(63,86,196,.45)}
.mf-btn.mf-dragging{opacity:.38}
.mf-col.mf-over{border-color:var(--c)}
.mf-btn.mf-ins-top{box-shadow:inset 0 2px 0 var(--c)}
.mf-hint{position:relative;z-index:2;margin-top:11px;font-size:11.5px;line-height:1.6;color:#9aa2b6}

html[data-theme="dark"] .mf-btn{color:var(--ink-2);background:rgba(255,255,255,.05);
  border-color:var(--hair-strong,rgba(255,255,255,.13))}
html[data-theme="dark"] .mf-btn:hover{background:rgba(255,255,255,.09)}
html[data-theme="dark"] .mf-btn-main{color:#fff}
html[data-theme="dark"] .mf-badge{background:rgba(21,19,31,.88);color:var(--c)}
html[data-theme="dark"] .mf-btn-main .mf-badge{background:rgba(255,255,255,.25);color:#fff}
html[data-theme="dark"] .mf-hint{color:var(--ink-3)}

/* [v2 修复] 按钮列内容会把 auto-fit 轨道撑到 min-content 之上 → 六环掉行；
   压回 min-width:0 并允许按钮文字断行，轨道才能收在 112px */

/* [v2] 列卡片（承 .mf-node 视觉语言：白底细描边 + 数轴段），min-width:0 防 auto-fit 被内容撑掉行 */
.mf-col{--nbg:#fbfcff;position:relative;display:flex;flex-direction:column;align-items:flex-start;
  min-width:0;padding:11px 10px 10px;border-radius:14px;background:transparent;border:1px solid #e8edf8;
  transition:transform .16s ease,box-shadow .16s ease,border-color .16s ease,background .16s ease}
/* [批167g] 列卡片改「透明」——动线走 z-index:0 下层时能透过列内空白/列间缝隙显示
   （英语页 6 列实测 background:rgba(0,0,0,0) 正是这个效果；实心卡片会把下层线整列遮死） */
.mf-col:hover{background:rgba(63,86,196,.045);border-color:var(--c);box-shadow:0 13px 26px -16px rgba(63,86,196,.5)}
.mf-btn span{flex:1 1 0%;min-width:0;word-break:break-all;text-align:left}

/* [v3] 深色档补全：v2 新增的列卡片/按钮/徽标/芯片（此前深色段只覆盖 v1 的 .mf-node） */
html[data-theme="dark"] .mf-col{--nbg:var(--surface,#1E1B2E);background:transparent;border-color:var(--hair-strong,rgba(255,255,255,.13))}
html[data-theme="dark"] .mf-col:hover{background:rgba(255,255,255,.045);border-color:var(--c);box-shadow:0 13px 26px -16px rgba(0,0,0,.65)}
html[data-theme="dark"] .mf-btn{background:rgba(255,255,255,.05);border-color:rgba(255,255,255,.14);color:#c6cde0}
html[data-theme="dark"] .mf-btn:hover{background:rgba(255,255,255,.11);border-color:var(--c);color:#eef1fb;transform:translateY(-1px)}
html[data-theme="dark"] .mf-btn-main{color:#fff;background:var(--c);border-color:transparent}
html[data-theme="dark"] .mf-btn-main:hover{background:var(--c);color:#fff;filter:brightness(1.1)}
html[data-theme="dark"] .mf-badge{background:#161d33;color:#cdd6f0;border-color:rgba(255,255,255,.24);box-shadow:0 2px 6px -3px rgba(0,0,0,.55)}
html[data-theme="dark"] .mf-chip{background:rgba(255,255,255,.05);border-color:rgba(255,255,255,.14);color:#c6cde0}
html[data-theme="dark"] .mf-chip:hover{background:#5b6fe0;color:#fff;border-color:transparent}
html[data-theme="dark"] .mf-foot-lab{color:var(--ink-3,#8a93ad)}
html[data-theme="dark"] .mf-sep{background:rgba(255,255,255,.14)}
html[data-theme="dark"] .mf-hint{color:var(--ink-3,#8a93ad)}
html[data-theme="dark"] .mf-track{opacity:.5}
/* ============================================================
   v4（2026-10-12 批167）：六步动线（接真学情）+ 环节正式名 + 8 张核心卡
   母题延续「草稿纸网格 + 数轴进程线」：动线走铅笔虚线流水（细实底 + 六环渐变主线 +
   白色流动虚线 + 箭头），区别于英语页的航图弧线；芯片/建议条同数学紫蓝语汇
   ============================================================ */

/* 环节正式名辅注：口语主名下的课程正式称谓（诊断/学习/练习/纠错/复习/测验） */
.mf-form{display:block;margin-top:1px;font-size:10.5px;font-weight:600;font-style:normal;color:#8a93ad;letter-spacing:.5px}

/* 8 张核心能力卡标记：按钮尾部小紫点（主按钮内反白） */
.mf-core-dot{flex:0 0 auto;width:5px;height:5px;border-radius:50%;background:#6D5EFC;
  box-shadow:0 0 0 2px rgba(109,94,252,.18)}
.mf-btn-main .mf-core-dot{background:#fff;box-shadow:0 0 0 2px rgba(255,255,255,.4)}

/* 今天想怎么走 · 动线芯片 */
.mf-routes{position:relative;z-index:2;display:flex;align-items:center;gap:7px;flex-wrap:wrap;margin-top:13px}
.mf-routes-lab{flex:0 0 auto;font-size:12px;font-weight:800;color:#4d5878;letter-spacing:.2px}
.mf-route{appearance:none;cursor:pointer;font-family:inherit;font-size:12px;font-weight:700;color:#4d5878;
  padding:5px 11px;border-radius:999px;background:#f6f8ff;border:1px solid #e6ecfa;
  transition:background .15s ease,color .15s ease,border-color .15s ease,transform .15s ease}
.mf-route:hover{background:#fff;border-color:#3f56c4;color:#3f56c4;transform:translateY(-1px)}
.mf-route.on{color:#fff;background:linear-gradient(120deg,#3f56c4,#6D5EFC);border-color:transparent;
  box-shadow:0 8px 16px -9px rgba(63,86,196,.6)}
/* 专属推荐：暖色呼吸，区别于常规动线 */
.mf-route[data-route="advice"].on{background:linear-gradient(120deg,#6D5EFC,#FF6B35);
  animation:mfRoutePulse 2.4s ease-in-out infinite}
@keyframes mfRoutePulse{0%,100%{box-shadow:0 8px 16px -9px rgba(63,86,196,.6)}
  50%{box-shadow:0 8px 22px -6px rgba(255,107,53,.66)}}

/* 小伴建议条（真学情话术） */
.mf-advice{position:relative;z-index:2;display:none;margin-top:11px;font-size:12.5px;line-height:1.65;color:#3f56c4;
  background:rgba(63,86,196,.07);border:1px solid rgba(63,86,196,.18);border-radius:10px;padding:8px 12px}
.mf-advice .mf-mascot-ico{display:inline-block;width:22px;height:22px;margin-right:5px;vertical-align:-6px;
  border-radius:50%;object-fit:cover;background:#fff;box-shadow:0 2px 5px -2px rgba(63,86,196,.35)}

/* 动线 SVG 覆盖层：置于列卡片之下（卡片 z-index:2 压在线上） */
.mth-flow-wrap{position:relative;margin-top:32px}
.mth-flow-wrap .mth-flow-axis{margin-top:0}
.mf-flow{position:absolute;top:0;left:0;z-index:0;pointer-events:none;overflow:visible}
/* [批167g] 线回到列卡片下层（z-index:0）——列卡片已改透明，线在列内空白与列间缝隙全程可见，
   只被按钮本身遮住 = 英语页观感；挖洞(167c)/航带(167e)方案一并作废 */
.mf-base{fill:none;stroke:#dfe6f7;stroke-width:3;stroke-linecap:round;opacity:.85}
.mf-arc{fill:none;stroke:url(#mfGrad);stroke-width:3;stroke-linecap:round;
  filter:drop-shadow(0 1px 3px rgba(63,86,196,.28))}
.mf-flowdash{fill:none;stroke:#fff;stroke-width:2.6;stroke-linecap:round;
  stroke-dasharray:16 58;animation:mfFlow 1.7s linear infinite}
.mf-head{fill:#3f56c4}
@keyframes mfFlow{from{stroke-dashoffset:0}to{stroke-dashoffset:-74}}
/* 动线上的节点：命中高亮 / 未命中淡化 */
.mf-btn.is-active{border-color:var(--c);
  box-shadow:0 0 0 2px var(--c),0 14px 26px -14px rgba(63,86,196,.6);transform:translateY(-1px)}
.mf-btn.is-dim{opacity:.42;filter:saturate(.55)}
.mf-btn.is-dim:hover{opacity:.75}

/* ---- 深色：夜航草稿纸 ---- */
html[data-theme="dark"] .mf-form{color:var(--ink-3)}
html[data-theme="dark"] .mf-routes-lab{color:var(--ink-2)}
html[data-theme="dark"] .mf-route{color:var(--ink-2);background:rgba(255,255,255,.05);
  border-color:rgba(255,255,255,.14)}
html[data-theme="dark"] .mf-route:hover{background:rgba(255,255,255,.1);color:#C9BEFF;border-color:#6D5EFC}
html[data-theme="dark"] .mf-route.on{color:#fff}
html[data-theme="dark"] .mf-advice{color:#C9BEFF;background:rgba(109,94,252,.12);
  border-color:rgba(155,140,255,.3)}
html[data-theme="dark"] .mf-base{stroke:rgba(255,255,255,.16)}
html[data-theme="dark"] .mf-flowdash{stroke:rgba(21,19,31,.86)}
html[data-theme="dark"] .mf-head{fill:#C9BEFF}