/* ===========================================================
   学生端样式（移动优先 · 明亮版）
   =========================================================== */

body.student {
  padding-bottom: calc(112px + env(safe-area-inset-bottom));
}

/* ---------- 顶栏 + 页面导航 ---------- */
/* student / idea 两页共用：品牌行和页签一起吸顶，滚动时始终能切页 */
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  width: 100%;
  max-width: 760px;
  margin: 0 auto;
  padding: 13px 18px 9px;
}

/* 两个页签：探究过程 / 改进方法 */
.pager {
  display: flex;
  gap: 7px;
  width: 100%;
  max-width: 760px;
  margin: 0 auto;
  padding: 0 16px 11px;
}

.pager .pg {
  flex: 1;
  min-width: 0;
  padding: 9px 10px;
  border-radius: 11px;
  border: 1px solid transparent;
  background: var(--surface-2);
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--txt-soft);
  text-align: center;
  text-decoration: none;
  transition: all 0.16s ease;
}

.pager .pg:active {
  transform: scale(0.98);
}

.pager .pg:hover {
  color: var(--brand);
}

.pager .pg.on {
  color: #0a6b9d;
  background: linear-gradient(135deg, #e6f4fd, #ececfe);
  border-color: rgba(11, 135, 199, 0.45);
  box-shadow: 0 2px 10px rgba(11, 135, 199, 0.16);
}

.brand {
  display: flex;
  align-items: center;
  gap: 11px;
}

.brand .logo {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  color: var(--brand);
  background: var(--brand-soft);
  border: 1px solid rgba(11, 135, 199, 0.2);
}

.brand .logo svg { width: 21px; height: 21px; }

.brand .t {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--txt);
}

.brand .s {
  font-size: 12px;
  color: var(--dim);
  margin-top: 1px;
}

/* ---------- 顶栏右侧：组别按钮 + 连接状态 ---------- */
.top-right {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: none;
}

/* 组别只在这里显示，主界面不再摆 9 个按钮，避免学生做实验时误点换组 */
.group-chip {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 7px 11px;
  border-radius: 999px;
  background: var(--brand-soft);
  border: 1px solid rgba(11, 135, 199, 0.32);
  font-size: 12.5px;
  font-weight: 700;
  line-height: 1;
  color: #0a6b9d;
  transition: all 0.15s ease;
}

.group-chip b {
  font-size: 14.5px;
  font-weight: 900;
  padding: 0 1px;
}

.group-chip .chip-edit {
  margin-left: 5px;
  padding-left: 7px;
  border-left: 1px solid rgba(11, 135, 199, 0.28);
  font-size: 11px;
  font-weight: 600;
  color: var(--dim);
}

.group-chip:active {
  transform: scale(0.96);
}

.group-chip:hover {
  border-color: rgba(11, 135, 199, 0.6);
}

/* 窄屏把「已连接」三个字收起来，只留圆点，别把组号挤掉 */
@media (max-width: 430px) {
  #connText {
    display: none;
  }
}

/* ---------- 任务条 ---------- */
.task {
  /* 和卡片同宽对齐：移动端两侧各留 16，宽屏锁 728 居中 */
  width: calc(100% - 32px);
  max-width: 728px;
  margin: 14px auto 0;
  padding: 11px 16px;
  border-radius: 13px;
  font-size: 13.5px;
  color: #14577b;
  background: linear-gradient(100deg, #e7f4fb, #eef0fd);
  border: 1px solid rgba(11, 135, 199, 0.16);
  text-align: center;
}

.task b {
  color: var(--brand);
  font-size: 15px;
  padding: 0 2px;
}

/* ---------- 内容区 ---------- */
.stack {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 14px 16px 24px;
  max-width: 760px;
  margin: 0 auto;
}

.card {
  padding: 16px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: #ffffff;
  box-shadow: var(--shadow);
}

.step-head {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--txt);
  margin-bottom: 4px;
}

.step-head .num {
  width: 24px;
  height: 24px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  font-size: 13px;
  font-weight: 800;
  color: #ffffff;
  background: linear-gradient(135deg, #35b3ea, #5b5bd6);
  flex: none;
}

.step-head .hist-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 4px rgba(14, 154, 114, 0.14);
  margin-left: 8px;
}

.hint {
  margin: 2px 0 13px 34px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--dim);
}

.hint .hint-sub {
  display: inline-block;
  margin-top: 3px;
  color: rgba(11, 135, 199, 0.85);
  font-weight: 600;
}

/* ---------- 组别 ---------- */
.group-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 9px;
  margin-top: 12px;
}

.group-btn {
  position: relative;
  padding: 14px 6px;
  border-radius: 13px;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  transition: all 0.16s ease;
}

.group-btn .n {
  font-size: 21px;
  font-weight: 800;
  letter-spacing: -0.02em;
  display: block;
  line-height: 1.1;
  color: var(--txt);
}

.group-btn .u {
  font-size: 11px;
  color: var(--dim);
  margin-top: 2px;
  letter-spacing: 0.06em;
}

.group-btn:active { transform: scale(0.96); }

.group-btn.on {
  border-color: rgba(11, 135, 199, 0.65);
  background: var(--brand-soft);
  box-shadow: 0 0 0 1px rgba(11, 135, 199, 0.45), 0 6px 16px rgba(11, 135, 199, 0.12);
}

.group-btn.on .n { color: var(--brand); }
.group-btn.on .u { color: var(--brand); }

/* ---------- 通用选项 ---------- */
.opt-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.opt {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 7px;
  padding: 7px 7px 9px;
  border-radius: 13px;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  text-align: center;
  transition: all 0.16s ease;
  min-width: 0;
}

.opt:active { transform: scale(0.97); }

/* 材料实拍图 */
.opt .thumb {
  display: block;
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 9px;
  overflow: hidden;
  background: #f6fafc;
  border: 1px solid var(--line);
}

.opt .thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* 没有配图时的兜底：首字 */
.opt .thumb.ph {
  display: grid;
  place-items: center;
  font-size: 20px;
  font-weight: 800;
  color: var(--dim);
}

.opt .name {
  font-size: 13.5px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--txt);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 选中打勾 */
.opt .tick {
  position: absolute;
  top: 2px;
  right: 2px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 11px;
  font-weight: 800;
  color: #ffffff;
  background: var(--brand);
  border: 2px solid #ffffff;
  box-shadow: 0 1px 4px rgba(12, 42, 66, 0.25);
  opacity: 0;
  transform: scale(0.6);
  transition: opacity 0.14s ease, transform 0.14s ease;
}

.opt.on {
  border-color: rgba(11, 135, 199, 0.75);
  background: var(--brand-soft);
  box-shadow: 0 0 0 1.5px rgba(11, 135, 199, 0.55);
}

.opt.on .thumb {
  border-color: rgba(11, 135, 199, 0.45);
}

.opt.on .tick {
  opacity: 1;
  transform: scale(1);
}

.opt.on .name { color: #0a6b9d; }

/* ---------- 瓶子 ---------- */
.bottle-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 9px;
  margin-top: 12px;
}

.bottle {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 9px 9px 11px;
  border-radius: 14px;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  transition: all 0.16s ease;
  min-width: 0;
}

/* 瓶子实拍图：3:4 竖版，跟导出的图比例一致，瓶子不会缩成一条 */
.bottle .thumb {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 4;
  border-radius: 10px;
  overflow: hidden;
  background: #f6fafc;
  border: 1px solid var(--line);
}

.bottle .thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* 没配图时的矢量瓶身兜底 */
.bottle .thumb.jar {
  width: 44px;
  flex: none;
  height: 60px;
  margin: 34px auto;
  border-radius: 7px 7px 9px 9px;
  border: 2px solid rgba(28, 46, 66, 0.32);
  background: transparent;
  position: relative;
}

.bottle .thumb.jar::before {
  content: '';
  position: absolute;
  top: -7px;
  left: 50%;
  transform: translateX(-50%);
  width: 14px;
  height: 7px;
  border-radius: 4px 4px 0 0;
  background: rgba(28, 46, 66, 0.32);
}

.bottle .lab {
  font-size: 15px;
  font-weight: 700;
  color: var(--txt);
}

.bottle:active { transform: scale(0.97); }

/* 选中打勾 */
.bottle .tick {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 11px;
  font-weight: 800;
  color: #ffffff;
  background: var(--brand);
  border: 2px solid #ffffff;
  box-shadow: 0 1px 4px rgba(12, 42, 66, 0.25);
  opacity: 0;
  transform: scale(0.6);
  transition: opacity 0.14s ease, transform 0.14s ease;
}

.bottle.on {
  border-color: rgba(11, 135, 199, 0.75);
  background: var(--brand-soft);
  box-shadow: 0 0 0 1.5px rgba(11, 135, 199, 0.55);
}

.bottle.on .thumb { border-color: rgba(11, 135, 199, 0.45); }
.bottle.on .thumb.jar { border-color: var(--brand); }
.bottle.on .thumb.jar::before { background: var(--brand); }
.bottle.on .tick { opacity: 1; transform: scale(1); }
.bottle.on .lab { color: #0a6b9d; }

/* ---------- 成功失败 ---------- */
.result-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 9px;
  margin-top: 14px;
}

.result-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
  padding: 17px 10px 15px;
  border-radius: 15px;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  transition: all 0.16s ease;
}

.result-btn .ico {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 19px;
  font-weight: 800;
  margin-bottom: 5px;
  border: 1px solid var(--line-strong);
  color: var(--dim);
  background: #ffffff;
}

.result-btn .lab {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--txt);
}

.result-btn .sub {
  font-size: 11.5px;
  color: var(--dim);
  text-align: center;
  line-height: 1.35;
}

.result-btn:active { transform: scale(0.97); }

.result-btn[data-success='true'].on {
  border-color: rgba(14, 154, 114, 0.6);
  background: var(--ok-soft);
  box-shadow: 0 0 0 1px rgba(14, 154, 114, 0.4), 0 8px 20px rgba(14, 154, 114, 0.12);
}

.result-btn[data-success='true'].on .ico {
  background: var(--ok);
  border-color: transparent;
  color: #ffffff;
}

.result-btn[data-success='true'].on .lab { color: var(--ok-strong); }

.result-btn[data-success='false'].on {
  border-color: rgba(217, 84, 104, 0.55);
  background: var(--bad-soft);
  box-shadow: 0 0 0 1px rgba(217, 84, 104, 0.35), 0 8px 20px rgba(217, 84, 104, 0.12);
}

.result-btn[data-success='false'].on .ico {
  background: var(--bad);
  border-color: transparent;
  color: #ffffff;
}

.result-btn[data-success='false'].on .lab { color: var(--bad-strong); }

/* ---------- 历史 ---------- */
.history-card {
  border-color: rgba(14, 154, 114, 0.22);
  background: linear-gradient(180deg, #f4fbf8, #ffffff);
}

.timeline {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.tl-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 11px;
  background: #ffffff;
  border: 1px solid var(--line);
  font-size: 13.5px;
}

.tl-item .pn {
  flex: none;
  padding: 3px 9px;
  border-radius: 7px;
  font-size: 11.5px;
  font-weight: 800;
  letter-spacing: 0.02em;
  background: var(--surface-2);
  color: var(--txt-soft);
  white-space: nowrap;
}

.tl-item.ok .pn { background: rgba(14, 154, 114, 0.14); color: var(--ok-strong); }
.tl-item.bad .pn { background: rgba(217, 84, 104, 0.12); color: var(--bad-strong); }

.tl-item .detail {
  flex: 1;
  min-width: 0;
  color: var(--txt-soft);
  line-height: 1.4;
}

.tl-item .detail b { font-weight: 700; color: var(--txt); }

.tl-item .time {
  flex: none;
  font-size: 12px;
  color: var(--dim);
  font-variant-numeric: tabular-nums;
}

.tl-item.ok { border-color: rgba(14, 154, 114, 0.3); }
.tl-item.bad { border-color: rgba(217, 84, 104, 0.26); }

.tl-item .res {
  flex: none;
  font-size: 12px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 999px;
}

.tl-item.ok .res { color: var(--ok-strong); background: var(--ok-soft); }
.tl-item.bad .res { color: var(--bad-strong); background: var(--bad-soft); }

.hist-tip {
  margin-top: 12px;
  font-size: 12px;
  color: var(--dim);
  text-align: center;
  line-height: 1.6;
}

/* ---------- 提交条 ---------- */
.submit-bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px calc(12px + env(safe-area-inset-bottom));
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(16px);
  border-top: 1px solid var(--line);
  box-shadow: 0 -6px 20px rgba(31, 52, 74, 0.06);
}

.submit-bar .summary {
  flex: 1;
  min-width: 0;
  font-size: 13px;
  line-height: 1.45;
  color: var(--dim);
}

.submit-bar .summary b {
  color: var(--brand);
  font-weight: 700;
}

.submit-bar .summary b.res.ok { color: var(--ok-strong); }
.submit-bar .summary b.res.bad { color: var(--bad-strong); }

.submit-bar .summary .sum-hint {
  font-size: 11.5px;
  color: var(--dim);
}

.submit-bar .submit {
  flex: none;
  padding: 14px 22px;
  font-size: 15.5px;
  border-radius: 14px;
}

/* 学生端 toast 上移，避免被提交条挡住 */
body.student #toast {
  bottom: calc(96px + env(safe-area-inset-bottom));
}

@media (min-width: 560px) {
  /* 大屏一行放满 6 个材料，跟课件的材料超市一致 */
  .opt-grid { grid-template-columns: repeat(6, 1fr); }
  .opt .name { font-size: 14px; }
  .group-grid { grid-template-columns: repeat(5, 1fr); }
  /* 瓶子图是 3:4 竖图，大屏要限宽，否则会撑成巨幅照片 */
  .bottle-grid { max-width: 460px; margin: 12px auto 0; }
  .bottle .thumb { max-width: 165px; margin: 0 auto; }
}

/* ---------- 选组弹窗 ---------- */
.modal {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: grid;
  place-items: center;
  padding: 18px;
}

.modal[hidden] {
  display: none;
}

.modal-mask {
  position: absolute;
  inset: 0;
  background: rgba(18, 32, 48, 0.44);
  backdrop-filter: blur(3px);
  animation: modalFade 0.18s ease;
}

.modal-card {
  position: relative;
  width: min(100%, 420px);
  max-height: 88vh;
  overflow: auto;
  padding: 22px 18px 16px;
  border-radius: 20px;
  background: #ffffff;
  box-shadow: var(--shadow-lg);
  animation: modalPop 0.22s cubic-bezier(0.22, 1, 0.36, 1);
}

.modal-title {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: var(--txt);
  text-align: center;
}

.modal-sub {
  margin: 7px 0 16px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--dim);
  text-align: center;
}

/* 弹窗里固定 3 列九宫格，跟「第几组」的直觉一致 */
.modal .group-grid {
  grid-template-columns: repeat(3, 1fr);
  gap: 9px;
  margin-top: 0;
}

.modal .group-btn {
  padding: 15px 6px;
}

.modal-foot {
  display: flex;
  gap: 10px;
  margin-top: 16px;
}

.modal-foot .btn {
  flex: 1;
  padding: 13px 0;
  font-size: 15px;
  border-radius: 13px;
}

@keyframes modalFade {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes modalPop {
  from { opacity: 0; transform: translateY(12px) scale(0.97); }
  to { opacity: 1; transform: none; }
}