/* ============================================================
   join.css — 加入实验室
   · 整体：DeepSeek 深色风格（暗底、圆角大卡片、柔光、蓝紫渐变点缀）
   · 三个阶段 = 瑞士网格"三个框"（01 风格：连体三框，切忌三竖列）
   · 点击按钮内容在下方呈现（同页展开 + 焦点下移）
   · 门禁：阶段2 需阶段1；阶段3 需阶段1+2；重置按钮
   ============================================================ */

.section-join {
  background:
    radial-gradient(90% 60% at 85% -10%, rgba(120, 92, 255, .12), transparent 60%),
    radial-gradient(70% 50% at 8% 110%, rgba(77, 159, 255, .10), transparent 55%),
    #0d0f14;
}
.join-head { border-bottom-color: rgba(255, 255, 255, .08); }

.join-phase-wrapper {
  max-width: 1360px;
  margin: 0 auto 30px;
}

/* ---- 瑞士网格三框（连体：共用边框，非竖列） ---- */
.join-phases {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border: 2px solid var(--swiss-line);
  background: #fff;
  border-radius: 14px;
  overflow: hidden;
  box-shadow: 0 24px 70px rgba(0, 0, 0, .45);
}
.join-phase {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 24px 20px;
  background: #fff;
  color: var(--swiss-ink);
  border: none;
  border-left: 2px solid var(--swiss-line);
  text-align: left;
  transition: background .2s;
  min-height: 190px;
}
.join-phase:first-child { border-left: none; }
.join-phase:hover { background: #f8f8f6; }
.join-phase .jp-num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .3em;
  color: var(--swiss-blue);
}
.join-phase .jp-title { font-size: 22px; font-weight: 800; letter-spacing: .02em; }
.join-phase .jp-desc { font-size: 13px; color: #4b4b4b; line-height: 1.7; flex: 1; }
.join-phase .jp-state {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  font-weight: 700;
}
.join-phase .jp-arrow {
  margin-left: auto;
  width: 34px; height: 34px;
  border-radius: 50%;
  border: 2px solid var(--swiss-ink);
  display: flex; align-items: center; justify-content: center;
  font-size: 15px;
  transition: all .2s;
  flex: none;
}
.join-phase:hover .jp-arrow { background: var(--swiss-ink); color: #fff; }
.join-phase.disabled { cursor: not-allowed; opacity: .62; }
.join-phase.disabled:hover { background: #fff; }
.join-phase.disabled .jp-arrow { border-color: #999; color: #666; }
.join-phase.done { background: #eef6ff; }
.join-phase.done .jp-state { color: #0d7a3f; }

/* ---- 阶段内容区（点击后在下方呈现 + 焦点下移） ---- */
.join-phase-content {
  margin-top: 26px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, .12);
  background: rgba(255, 255, 255, .04);
  padding: 30px 32px;
  min-height: 120px;
}
.jpc-head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 22px;
}
.jpc-title { font-size: 21px; font-weight: 800; letter-spacing: .03em; }
.jpc-sub { font-size: 12.5px; color: var(--text-2); }
.jpc-guide { font-size: 12.5px; color: var(--text-1); background: rgba(77, 159, 255, .07); border: 1px dashed rgba(77, 159, 255, .3); border-radius: 10px; padding: 11px 15px; line-height: 1.8; margin-bottom: 20px; }

/* 报名表单（三部分 + 左表单右QQ列布局） */
.apply-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 270px;
  gap: 26px;
  align-items: start;
}
/* 电脑端：每部分内元素按"行"排 —— Ⅰ三元素一行 / Ⅱ两元素一行 / Ⅲ一元素一行 */
.apply-form { display: grid; gap: 18px 22px; max-width: 860px; }
.af-field { display: flex; flex-direction: column; gap: 6px; }
.af-field.full { grid-column: 1 / -1; }
.af-label { font-size: 12.5px; color: var(--text-1); letter-spacing: .03em; }
.af-label em { color: var(--bad); font-style: normal; }
.af-hint { font-size: 11px; color: var(--text-2); }
.af-input, .af-select, .af-textarea {
  background: #0f141c;
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: 10px;
  color: var(--text-0);
  font-size: 13.5px;
  padding: 11px 14px;
  outline: none;
  transition: border-color .2s, box-shadow .2s;
}
.af-input:focus, .af-select:focus, .af-textarea:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(77, 159, 255, .18);
}
.af-input:disabled, .af-select:disabled, .af-textarea:disabled { opacity: .62; cursor: not-allowed; }
.af-readonly { background: rgba(77, 159, 255, .06); border-style: dashed; color: #cfe3ff; }
/* 限位文本域（不再自由拉伸）：固定高度 + 字数统计 */
.af-textarea { resize: none; min-height: 96px; max-height: 96px; }
.af-count { font-size: 11px; color: var(--text-2); text-align: right; font-family: var(--font-mono); }
/* 三部分与分隔线：电脑端仅部分之间画横线（Row 内不画）
   序号列用绝对定位（不参与 grid 轨道），避免完成态 display:none 后重排塌陷 */
.af-section { display: grid; grid-template-columns: minmax(0, 1fr); gap: 12px; align-items: start; position: relative; padding-left: 30px; }
.af-num {
  position: absolute;
  left: 0;
  top: 8px;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 800;
  color: var(--accent-blue);
  letter-spacing: .1em;
}
.af-section-grid { display: grid; gap: 16px 22px; }
.af-section-grid > .af-field.full { grid-column: 1 / -1; }
/* 申请成功后：横线消失、序号淡出；保留原行布局（Ⅰ 3列/Ⅱ 2列/Ⅲ 1列），
   左侧不压缩 —— 右侧仅留 QQ 群图列（270px），表单仍清晰可读 */
.apply-form.done .af-divider { display: none; }
.apply-form.done .af-section { padding-left: 0; }
.apply-form.done .af-num { display: none; }
.apply-form.done .af-input, .apply-form.done .af-select, .apply-form.done .af-textarea { opacity: 1; }
.af-divider { height: 1px; background: linear-gradient(90deg, rgba(255,255,255,.22), rgba(255,255,255,.04)); margin: 8px 0 14px; }
/* 提交成功态：QQ 群竖列（图宽与示例一致，高度可裁剪） */
.apply-qq {
  position: sticky;
  top: 118px;
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: 14px;
  background: rgba(255, 255, 255, .04);
  padding: 16px 14px;
  text-align: center;
}
.aqq-title { font-size: 14.5px; font-weight: 800; color: #9ecbff; margin-bottom: 10px; letter-spacing: .04em; }
.aqq-imgbox {
  width: 100%;
  height: 300px;              /* 竖直高度可裁剪：容器限高 */
  overflow: hidden;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, .16);
}
.aqq-imgbox img { width: 100%; height: 100%; object-fit: cover; object-position: top; display: block; }
.aqq-note { margin-top: 10px; font-size: 12px; color: var(--text-2); font-family: var(--font-mono); }
/* 提交按钮行：与上方表单元素拉开间距（不再挤在一起） */
.apply-submit-row {
  grid-column: 1 / -1;
  margin-top: 14px;
  display: flex;
  justify-content: flex-start;
}
/* 提交按钮三态：学号登录=封面主色材质 / 游客=暗色禁用 / 已提交 */
.af-submit {
  padding: 13px 34px;
  border-radius: 10px;
  background: linear-gradient(120deg, #4d9fff, #7b5cff);
  border: none;
  color: #fff;
  font-size: 14.5px;
  font-weight: 700;
  letter-spacing: .1em;
  box-shadow: 0 12px 34px rgba(77, 159, 255, .35);
  transition: transform .18s, box-shadow .18s;
}
.af-submit:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 16px 44px rgba(77, 159, 255, .5); }
/* 学号登录态：与封面"学号登录"同材质（蓝色实心高亮） */
.af-submit-primary {
  background: #2f7bff;
  box-shadow: 0 0 0 1px rgba(255, 255, 255, .18) inset, 0 12px 36px rgba(47, 123, 255, .42);
}
.af-submit-primary:hover:not(:disabled) { background: #3c86ff; }
/* 游客态：暗色禁用（置于 disabled 规则之前，保证优先级） */
.af-submit-locked, .af-submit-locked:disabled {
  background: rgba(255, 255, 255, .05);
  border: 1px solid rgba(255, 255, 255, .12);
  color: rgba(255, 255, 255, .32);
  box-shadow: none;
  cursor: not-allowed;
  transform: none;
}
.af-submit-locked:hover { transform: none; box-shadow: none; }
/* 成功提交后的已提交按钮（仅 .af-submit 无 locked 类的 disabled 态） */
.af-submit:disabled:not(.af-submit-locked) {
  background: rgba(61, 220, 132, .1);
  border: 1px solid rgba(61, 220, 132, .35);
  color: rgba(185, 244, 210, .75);
}

/* ---------- 四方向并列卡 ---------- */
.dir-cards-block { max-width: 1360px; margin: 30px auto 0; }
.dir-cards-note { font-size: 12px; color: var(--text-2); letter-spacing: .1em; }
.dir-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}
.dir-card0 {
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 16px;
  overflow: hidden;
  background: rgba(255, 255, 255, .04);
  transition: transform .22s, border-color .22s, box-shadow .22s;
  display: flex;
  flex-direction: column;
}
.dir-card0:hover {
  transform: translateY(-5px);
  border-color: hsla(var(--dh, 210), 90%, 62%, .55);
  box-shadow: 0 22px 50px rgba(0, 0, 0, .45), 0 0 0 1px hsla(var(--dh, 210), 90%, 62%, .2);
}
.dc-imgbox { aspect-ratio: 4 / 3; overflow: hidden; }
.dc-imgbox img { width: 100%; height: 100%; object-fit: cover; transition: transform .4s ease; }
.dir-card0:hover .dc-imgbox img { transform: scale(1.06); }
.dc-title { padding: 13px 16px 4px; font-size: 16.5px; font-weight: 800; letter-spacing: .05em; }
.dc-title::before { content: ""; display: inline-block; width: 8px; height: 8px; border-radius: 2px; background: hsla(var(--dh, 210), 90%, 60%, .9); margin-right: 8px; vertical-align: middle; }
.dc-desc { padding: 0 16px 16px; font-size: 12.5px; color: var(--text-2); line-height: 1.8; flex: 1; }

/* ---------- 阶段3 学习：方向认知（立绘 + 引言 + 四方向按钮 + 展开图文） ---------- */
.learn-intro {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 26px;
  align-items: start;
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 16px;
  padding: 22px;
  background: rgba(255, 255, 255, .03);
}
.li-figure { border-radius: 12px; overflow: hidden; border: 1px solid rgba(255, 255, 255, .12); }
.li-figure img { width: 100%; display: block; }
.li-quote {
  font-family: var(--font-serif);
  font-size: 19px;
  line-height: 2;
  color: #f1e6d0;
  letter-spacing: .06em;
  margin-top: 6px;
}
.li-quote-src { font-size: 12px; color: var(--text-2); margin: 8px 0 18px; }
.li-post { font-size: 15px; font-weight: 800; color: #9ecbff; letter-spacing: .05em; }
.li-post-note { font-size: 12px; color: var(--text-2); margin-top: 4px; margin-bottom: 14px; }
.learn-dir-btns { display: flex; gap: 10px; flex-wrap: wrap; }
.learn-dir-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: 99px;
  border: 1px solid rgba(255, 255, 255, .2);
  background: rgba(255, 255, 255, .05);
  color: var(--text-0);
  font-size: 13.5px;
  letter-spacing: .06em;
  transition: all .2s;
}
.learn-dir-btn:hover { border-color: rgba(77, 159, 255, .6); background: rgba(77, 159, 255, .1); }
.learn-dir-btn.on { border-color: var(--accent-blue); background: rgba(77, 159, 255, .18); color: #fff; box-shadow: 0 0 18px rgba(77, 159, 255, .25); }
.ldb-ico {
  width: 22px; height: 22px;
  border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 11px;
  font-weight: 800;
  color: #fff;
  background: hsla(var(--dh, 210), 70%, 55%, .9);
}
.learn-dir-panels { margin-top: 14px; }
.ldp { border-radius: 12px; overflow: hidden; border: 1px solid rgba(255, 255, 255, .1); background: rgba(4, 18, 40, .35); }
.ldp-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  font-size: 13.5px;
  font-weight: 800;
  color: #9ecbff;
  border-bottom: 1px solid rgba(255, 255, 255, .08);
}
/* 编辑排版按钮（学习培养方向图文：与日历胶片窗一致的可编辑能力） */
.ldp-edit-btn {
  margin-left: auto;
  padding: 6px 14px;
  font-size: 12px;
  border-radius: 99px;
  border: 1px solid rgba(77, 159, 255, .5);
  background: rgba(77, 159, 255, .1);
  color: #cfe3ff;
  letter-spacing: .05em;
  transition: all .18s;
}
.ldp-edit-btn:hover { background: rgba(77, 159, 255, .22); transform: translateY(-1px); }
/* 内容完全展示：不设固定高度，按内容自适应（图片保持比例） */
.ldp-body { max-height: 0; overflow: hidden; transition: max-height .5s cubic-bezier(.25, .9, .3, 1); }
.ldp-body.open { max-height: 1400px; }
.ldp-stage { position: relative; overflow: hidden; min-height: 320px; padding: 18px; }
.ldp-item img { width: 100%; border-radius: 8px; border: 2px solid #f4ead6; box-shadow: 0 10px 26px rgba(0, 0, 0, .5); display: block; }
.ldp-txt { font-family: var(--font-serif); color: #f1e6d0; letter-spacing: .04em; line-height: 1.5; text-shadow: 0 2px 8px rgba(0, 0, 0, .6); }

/* ---- 方向图文内嵌编辑器 ---- */
.ldp-edit-toolbar {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  align-items: center;
  padding: 10px 12px;
  border-bottom: 1px solid rgba(255, 255, 255, .08);
  background: rgba(10, 16, 26, .6);
}
.ldp-edit-toolbar .ed-btn {
  background: rgba(77, 159, 255, .1);
  border: 1px solid rgba(77, 159, 255, .4);
  color: #cfe3ff;
  font-size: 12px;
  padding: 7px 14px;
  border-radius: 8px;
  transition: all .15s;
}
.ldp-edit-toolbar .ed-btn:hover { background: rgba(77, 159, 255, .22); }
.ldp-edit-toolbar .ed-file-label {
  margin: 0;
  padding: 7px 14px;
  border: 1px dashed rgba(77, 159, 255, .5);
  border-radius: 8px;
  color: #cfe3ff;
  font-size: 12px;
  cursor: pointer;
}
.ldp-edit-toolbar .ed-file-label:hover { background: rgba(77, 159, 255, .14); }
.dir-edit-hint {
  padding: 8px 14px;
  font-size: 11.5px;
  color: var(--text-2);
  border-bottom: 1px solid rgba(255, 255, 255, .08);
}
.dir-edit-side {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  padding: 10px 14px 12px;
  background: rgba(10, 16, 26, .5);
}
.dir-edit-side .ed-slider-row {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  color: #cfe3ff;
}
.dir-edit-side .ed-slider-row input[type="range"] { width: 110px; accent-color: #4d9fff; }
.ldp-item.postable { cursor: grab; position: absolute; }
.ldp-item.postable.selected { outline: 2px dashed rgba(255, 220, 140, .9); outline-offset: 2px; }

@media (max-width: 900px) {
  .dir-cards { grid-template-columns: repeat(2, 1fr); }
  .apply-wrap { grid-template-columns: 1fr; }
  .apply-qq { position: static; }
  .learn-intro { grid-template-columns: 1fr; }
}

/* 任务卡片 */
.task-list { display: grid; gap: 16px; max-width: 900px; }
.task-card {
  border: 1px solid rgba(255, 255, 255, .12);
  border-radius: 14px;
  background: rgba(255, 255, 255, .035);
  padding: 20px 22px;
  transition: border-color .2s;
}
.task-card.done { border-color: rgba(61, 220, 132, .55); background: rgba(61, 220, 132, .05); }
.task-card-head { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.task-card-title { font-size: 16.5px; font-weight: 800; }
.task-card-dirs { display: flex; gap: 6px; margin-left: auto; }
.task-dir-tag { font-size: 10.5px; color: #9ecbff; border: 1px solid rgba(77, 159, 255, .4); padding: 1px 8px; border-radius: 99px; }
.task-banner { font-size: 12px; color: var(--text-1); margin: 8px 0 14px; }
.task-guide { font-size: 12px; color: var(--text-2); line-height: 1.9; margin-bottom: 16px; }
.task-guide li { margin-left: 20px; }
.task-payload { margin-bottom: 14px; }
.task-foot { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.task-submit {
  padding: 10px 26px;
  border-radius: 9px;
  background: linear-gradient(120deg, #4d9fff, #7b5cff);
  border: none;
  color: #fff;
  font-weight: 700;
  font-size: 13.5px;
  letter-spacing: .06em;
  transition: transform .15s;
}
.task-submit:hover { transform: translateY(-2px); }
.task-status { font-size: 12.5px; color: var(--text-2); font-family: var(--font-mono); }
.task-status.ok { color: var(--ok); }

/* 连线题 */
.wire-stage {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 70px 1fr;
  gap: 10px;
  border: 1px dashed rgba(255, 255, 255, .2);
  border-radius: 12px;
  padding: 16px;
  background: rgba(4, 18, 40, .4);
  min-height: 230px;
}
.wire-panel { display: flex; flex-direction: column; gap: 8px; }
.wire-panel-title { font-size: 12.5px; font-weight: 700; color: #9ecbff; margin-bottom: 2px; }
.wire-pin {
  padding: 10px 13px;
  border-radius: 9px;
  border: 1.5px solid rgba(255, 255, 255, .18);
  background: rgba(255, 255, 255, .05);
  color: var(--text-0);
  font-size: 13px;
  text-align: left;
  transition: all .15s;
  position: relative;
}
.wire-pin:hover { border-color: rgba(77, 159, 255, .6); }
.wire-pin.sel { border-color: var(--accent-blue); background: rgba(77, 159, 255, .18); box-shadow: 0 0 16px rgba(77, 159, 255, .3); }
.wire-pin.used { opacity: .38; cursor: not-allowed; }
.wire-svg { position: absolute; inset: 0; pointer-events: none; z-index: 2; }

/* 选择题 */
.q-item { margin-bottom: 18px; }
.q-text { font-size: 13.5px; font-weight: 600; margin-bottom: 9px; line-height: 1.7; }
.q-opts { display: grid; grid-template-columns: repeat(2, 1fr); gap: 9px; }
.q-opt {
  padding: 10px 14px;
  border-radius: 9px;
  border: 1.5px solid rgba(255, 255, 255, .14);
  background: rgba(255, 255, 255, .04);
  color: var(--text-1);
  font-size: 13px;
  text-align: left;
  transition: all .15s;
}
.q-opt:hover { border-color: rgba(77, 159, 255, .5); color: #fff; }
.q-opt.sel { border-color: var(--accent-blue); background: rgba(77, 159, 255, .2); color: #fff; }
.q-note { font-size: 12px; color: var(--text-2); margin-top: 10px; padding: 9px 13px; border-left: 3px solid var(--accent-blue); background: rgba(77, 159, 255, .06); border-radius: 0 8px 8px 0; }

/* 完成句 */
.sentence-banner {
  margin-top: 20px;
  padding: 16px 20px;
  border-radius: 12px;
  border: 1px solid rgba(61, 220, 132, .4);
  background: rgba(61, 220, 132, .07);
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.sentence-words {
  font-size: 25px;
  font-weight: 900;
  letter-spacing: .12em;
  color: var(--ok);
  text-shadow: 0 0 22px rgba(61, 220, 132, .4);
}
.sentence-note { font-size: 12.5px; color: var(--text-1); }

/* 学习培养 */
.learn-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; max-width: 900px; }
.learn-card {
  border: 1px solid rgba(255, 255, 255, .12);
  border-radius: 13px;
  padding: 16px 18px;
  background: rgba(255, 255, 255, .035);
  transition: transform .18s, border-color .18s;
}
.learn-card:hover { transform: translateY(-3px); border-color: rgba(77, 159, 255, .5); }
.learn-type {
  display: inline-block;
  font-size: 10.5px;
  color: #9ecbff;
  border: 1px solid rgba(77, 159, 255, .4);
  border-radius: 99px;
  padding: 1px 9px;
  margin-bottom: 8px;
}
.learn-title { font-size: 15px; font-weight: 700; }
.learn-desc { font-size: 12.5px; color: var(--text-2); margin-top: 5px; }
.learn-note { margin-top: 18px; font-size: 12px; color: var(--text-2); }

/* 重置按钮 */
.join-tools { display: flex; align-items: center; gap: 14px; margin-top: 20px; flex-wrap: wrap; }
.join-reset {
  padding: 9px 20px;
  border-radius: 99px;
  background: transparent;
  border: 1px solid rgba(255, 93, 93, .5);
  color: #ff9c9c;
  font-size: 12.5px;
  letter-spacing: .05em;
  transition: all .18s;
}
.join-reset:hover { background: rgba(255, 93, 93, .14); border-color: var(--bad); }
/* B-08 两步确认：第一次点击后的待确认态（变红提示，3s 未确认自动复原） */
.join-reset.arm { background: var(--bad); border-color: var(--bad); color: #fff; animation: armPulse 1s ease infinite; }
@keyframes armPulse { 0%, 100% { box-shadow: 0 0 0 0 rgba(255, 93, 93, .4); } 50% { box-shadow: 0 0 0 7px rgba(255, 93, 93, 0); } }
@media (prefers-reduced-motion: reduce) { .join-reset.arm { animation: none; } }
.join-reset-note { font-size: 11.5px; color: var(--text-2); }

/* ---- 常见问题 ---- */
.faq-block { max-width: 1060px; margin: 34px auto 0; padding-top: 24px; border-top: 1px solid rgba(255, 255, 255, .08); }
.faq-live {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .2em;
  color: var(--ok);
  border: 1px solid rgba(61, 220, 132, .4);
  border-radius: 99px;
  padding: 3px 11px;
  animation: faqLive 2s ease-in-out infinite;
}
@keyframes faqLive { 0%, 100% { box-shadow: 0 0 0 rgba(61, 220, 132, 0); } 50% { box-shadow: 0 0 14px rgba(61, 220, 132, .45); } }

.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-item {
  border-radius: 13px;
  border: 1px solid rgba(255, 255, 255, .1);
  background: rgba(255, 255, 255, .03);
  overflow: hidden;
  transition: border-color .2s;
}
.faq-item.open { border-color: rgba(77, 159, 255, .45); }
.faq-q {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 13px;
  padding: 15px 18px;
  background: transparent;
  border: none;
  color: var(--text-0);
  font-size: 14.5px;
  font-weight: 600;
  text-align: left;
  letter-spacing: .02em;
}
.faq-q:hover { background: rgba(255, 255, 255, .03); }
.faq-num { font-family: var(--font-mono); font-size: 11px; color: var(--accent-blue); flex: none; }
.faq-icon {
  margin-left: auto;
  width: 28px; height: 28px;
  flex: none;
  border-radius: 50%;
  border: 1.5px solid rgba(255, 255, 255, .25);
  display: flex; align-items: center; justify-content: center;
  font-size: 14px;
  color: var(--text-1);
  transition: all .25s;
}
.faq-item.open .faq-icon { transform: rotate(45deg); border-color: var(--accent-blue); color: var(--accent-blue); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height .45s cubic-bezier(.25, .9, .3, 1);
}
.faq-item.open .faq-a { max-height: 300px; }
.faq-a-inner {
  padding: 2px 20px 17px 48px;
  font-size: 13.5px;
  color: var(--text-1);
  line-height: 1.85;
}

@media (max-width: 900px) {
  .join-phases { grid-template-columns: 1fr; }
  .join-phase { border-left: none; border-top: 2px solid var(--swiss-line); min-height: 0; }
  .join-phase:first-child { border-top: none; }
  /* 手机端：全部竖向排列，每个部分之间画横线（行内不再并排） */
  .af-section-grid { grid-template-columns: 1fr !important; }
  .apply-form { grid-template-columns: 1fr; }
  /* 手机端成功后：横线消失，QQ 群图收在表单底部（整宽） */
  .apply-wrap { grid-template-columns: 1fr; }
  .apply-qq { position: static; }
  .learn-grid { grid-template-columns: 1fr; }
  .q-opts { grid-template-columns: 1fr; }
}