/* ============================================================
   作业管理 - 移动优先响应式 UI
   ============================================================ */
:root {
  --primary: #4f46e5;
  --primary-600: #4338ca;
  --primary-100: #eef2ff;
  --green: #16a34a;   --green-bg: #dcfce7;
  --blue: #2563eb;    --blue-bg: #dbeafe;
  --orange: #d97706;  --orange-bg: #fef3c7;
  --red: #dc2626;     --red-bg: #fee2e2;
  --ink: #0f172a;
  --ink-2: #475569;
  --ink-3: #94a3b8;
  --line: #e5e9f0;
  --bg: #f2f4f8;
  --card: #ffffff;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .05), 0 6px 18px rgba(15, 23, 42, .06);
  --topbar-h: 52px;
  --bnav-h: 58px;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "HarmonyOS Sans SC",
               "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.5;
}
svg.ic {
  width: 20px; height: 20px; flex: none;
  fill: none; stroke: currentColor; stroke-width: 2;
  stroke-linecap: round; stroke-linejoin: round;
}
svg.ic-lg { width: 26px; height: 26px; }
h1 { font-size: 20px; margin: 14px 0 10px; }
h2 { font-size: 16px; margin: 12px 0 8px; }
h3 { font-size: 15px; margin: 0 0 10px; }
a { color: var(--primary); text-decoration: none; }
.muted { color: var(--ink-2); }
.small { font-size: 12px; }
.text-red { color: var(--red); }
.empty { color: var(--ink-3); padding: 14px 0; text-align: center; }
.center { text-align: center; }

/* ---------------- 顶栏 ---------------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  max-width: 1080px; margin: 0 auto; height: var(--topbar-h);
  padding: 0 14px; display: flex; align-items: center; justify-content: space-between;
}
.brand {
  display: flex; align-items: center; gap: 9px;
  font-weight: 800; font-size: 17px; color: var(--ink);
}
.brand-mark {
  width: 26px; height: 26px; border-radius: 8px;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  display: flex; align-items: center; justify-content: center; color: #fff;
}
.brand-mark .ic { width: 16px; height: 16px; }
.topbar-right { display: flex; align-items: center; gap: 6px; }
.user-chip {
  display: flex; align-items: center; gap: 5px;
  font-size: 13px; color: var(--ink-2);
  background: var(--bg); border-radius: 999px; padding: 4px 10px;
}
.user-chip .ic { width: 15px; height: 15px; }
.toplink {
  display: flex; align-items: center; gap: 4px;
  font-size: 13px; color: var(--ink-2); padding: 6px 8px; border-radius: 8px;
}
.toplink:hover { background: var(--bg); color: var(--ink); }

/* ---------------- 底部导航(仅移动端) ---------------- */
.bottom-nav {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 60;
  display: flex;
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-top: 1px solid var(--line);
  height: calc(var(--bnav-h) + env(safe-area-inset-bottom));
  padding-bottom: env(safe-area-inset-bottom);
}
.bn-item {
  flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 2px; color: var(--ink-3); font-size: 11px;
}
.bn-item .ic { width: 22px; height: 22px; }
.bn-item.active { color: var(--primary); font-weight: 600; }
.bn-item.active .ic { stroke-width: 2.4; }

/* ---------------- 页面容器 ---------------- */
.page {
  max-width: 1080px; margin: 0 auto;
  padding: 8px 14px calc(var(--bnav-h) + 26px);
}
@media (min-width: 768px) {
  .bottom-nav { display: none; }
  .page { padding: 16px 22px 48px; }
  h1 { font-size: 24px; }
}

/* ---------------- 卡片 ---------------- */
.card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 14px; margin: 12px 0;
  box-shadow: var(--shadow);
}
@media (min-width: 768px) { .card { padding: 18px; } }
.grid { display: grid; grid-template-columns: 1fr; gap: 12px; }
@media (min-width: 620px) { .grid { grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); } }

/* 班级卡片 */
.class-card { display: block; color: inherit; position: relative; padding-right: 40px; }
.class-card:hover { border-color: var(--primary); }
.class-name { font-size: 16px; font-weight: 700; }
.class-meta { color: var(--ink-3); font-size: 12px; margin-top: 3px; }
.class-arrow {
  position: absolute; right: 14px; top: 50%; transform: translateY(-50%);
  color: var(--ink-3);
}
.dash-card { border: 1.5px dashed var(--line); color: var(--ink-3); text-align: center; justify-content: center; align-items: center; }
.dash-card:hover { border-color: var(--primary); color: var(--primary); }

/* 概览统计 */
.overview { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin: 12px 0; }
.ov-item {
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  padding: 10px 4px; text-align: center;
}
.ov-item b { font-size: 20px; display: block; line-height: 1.3; }
.ov-item span { font-size: 11px; color: var(--ink-3); }
@media (min-width: 768px) { .overview { gap: 12px; } .ov-item b { font-size: 24px; } }

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 7px;
  min-height: 40px; padding: 0 16px;
  border: 1px solid var(--line); border-radius: 10px;
  background: #fff; color: var(--ink);
  font-size: 14px; cursor: pointer; text-decoration: none;
  line-height: 1.3; white-space: nowrap;
}
.btn:hover { border-color: var(--primary); color: var(--primary); }
.btn-primary {
  background: var(--primary); border-color: var(--primary); color: #fff;
  box-shadow: 0 4px 14px rgba(79, 70, 229, .28);
}
.btn-primary:hover { background: var(--primary-600); border-color: var(--primary-600); color: #fff; }
.btn-danger { color: var(--red); border-color: #fecaca; }
.btn-danger:hover { background: var(--red-bg); color: var(--red); }
.btn-warn { color: var(--orange); border-color: #fde68a; }
.btn-warn:hover { background: var(--orange-bg); color: var(--orange); }
.btn-ghost { background: transparent; border-color: transparent; color: var(--ink-2); }
.btn-lg { min-height: 48px; font-size: 16px; border-radius: 12px; padding: 0 20px; width: 100%; }
.btn-sm { min-height: 30px; padding: 0 10px; font-size: 13px; border-radius: 8px; }
.btn-block { width: 100%; }
@media (min-width: 768px) {
  .btn { min-height: 36px; }
  .btn-lg { min-height: 44px; width: auto; }
}
.btn-row { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin: 8px 0; }
.sep { color: var(--ink-3); font-size: 13px; }
form.inline { display: inline; }
.inline-form { display: grid; grid-template-columns: 1fr; gap: 8px; margin-bottom: 8px; }
@media (min-width: 768px) {
  .inline-form { display: flex; flex-wrap: wrap; align-items: center; }
  .inline-form input, .inline-form select { width: auto; }
}
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-bottom: 8px; }
.form-grid .full { grid-column: 1 / -1; }
.form-grid .btn { margin-top: 2px; }
@media (max-width: 380px) { .form-grid { grid-template-columns: 1fr; } }

/* ---------------- 表单 ---------------- */
input, select, textarea {
  width: 100%;
  padding: 11px 12px;
  border: 1px solid var(--line); border-radius: 10px;
  font-size: 16px; background: #fff; color: var(--ink);
  -webkit-appearance: none; appearance: none;
}
input:focus, select:focus, textarea:focus {
  outline: 2px solid var(--primary); outline-offset: -1px; border-color: var(--primary);
}
textarea { resize: vertical; min-height: 110px; font-family: inherit; line-height: 1.6; }
@media (min-width: 768px) {
  input, select, textarea { font-size: 14px; padding: 8px 10px; }
}

/* 模式切换(单个/批量添加) */
.mode-toggle { display: inline-flex; gap: 4px; background: var(--ink-0); border: 1px solid var(--line); border-radius: 10px; padding: 3px; margin: 4px 0 10px; }
.mode-btn { min-height: 34px; padding: 0 14px; font-size: 13px; border: none; border-radius: 8px; background: transparent; color: var(--ink-2); cursor: pointer; }
.mode-btn.active { background: #fff; color: var(--primary); font-weight: 600; box-shadow: 0 1px 4px rgba(15, 23, 42, .08); }
.mode-btn:active { transform: scale(.97); }

/* 卡片标题行(标题 + 右侧操作/徽章) */
.card-head-row { display: flex; align-items: center; justify-content: space-between; gap: 10px; flex-wrap: wrap; margin-bottom: 4px; }
.card-head-row h3 { margin: 0; }

/* 复选框(账号管理等) */
input[type="checkbox"] {
  width: 18px; height: 18px; min-height: 18px; margin-right: 6px;
  -webkit-appearance: checkbox; appearance: auto;
  accent-color: var(--primary);
}
.checkbox-line { display: flex; align-items: center; gap: 4px; font-size: 14px; color: var(--ink); margin: 4px 0; }
select { background-image: linear-gradient(45deg, transparent 50%, var(--ink-3) 50%), linear-gradient(135deg, var(--ink-3) 50%, transparent 50%); background-position: calc(100% - 18px) 55%, calc(100% - 13px) 55%; background-size: 5px 5px; background-repeat: no-repeat; padding-right: 30px; }
label { display: block; font-size: 13px; color: var(--ink-2); margin: 10px 0 4px; }

/* ---------------- 表格(桌面) / 卡片(移动) ---------------- */
.table { width: 100%; border-collapse: collapse; font-size: 14px; margin-top: 6px; }
.table th { color: var(--ink-3); font-weight: 600; font-size: 12px; text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--line); white-space: nowrap; }
.table td { padding: 10px; border-bottom: 1px solid var(--line); vertical-align: middle; }
.table tbody tr:last-child td { border-bottom: none; }
.table td .inline { display: inline-flex; gap: 6px; align-items: center; }
.table td select { width: auto; }
.table-wrap { overflow-x: auto; }
@media (max-width: 767.98px) {
  .table thead { display: none; }
  .table, .table tbody, .table tr { display: block; width: 100%; }
  .table tr {
    background: #fff; border: 1px solid var(--line); border-radius: 12px;
    margin: 0 0 10px; padding: 2px 14px;
  }
  .table td {
    display: flex; justify-content: space-between; align-items: center; gap: 14px;
    padding: 8px 0; border-bottom: 1px dashed var(--line);
  }
  .table td:last-child { border-bottom: none; }
  .table td::before {
    content: attr(data-label);
    color: var(--ink-3); font-size: 12px; flex: none;
  }
  .table td .inline select { max-width: 110px; }
}

/* 名单(作业页)移动端专属布局 */
@media (max-width: 767.98px) {
  .roster thead { display: none; }
  .roster tbody { display: block; }
  .roster tr {
    display: grid;
    grid-template-columns: 1fr auto;
    grid-template-areas: "nm st" "no st" "meta st";
    align-items: center;
    background: #fff; border: 1px solid var(--line); border-radius: 12px;
    margin: 0 0 10px; padding: 10px 14px;
  }
  .roster td { display: block; border: none !important; padding: 1px 0; }
  .roster td.nm { grid-area: nm; font-weight: 700; font-size: 15px; }
  .roster td.no { grid-area: no; font-size: 12px; color: var(--ink-3); }
  .roster td.st { grid-area: st; }
  .roster td.meta { grid-area: meta; font-size: 11px; color: var(--ink-3); }
  .roster td::before { content: none !important; }
}

/* ---------------- 状态徽章 ---------------- */
.badge {
  display: inline-block; padding: 2px 10px; border-radius: 999px;
  font-size: 12px; font-weight: 600; line-height: 1.7; white-space: nowrap;
}
.b0 { background: var(--red-bg); color: var(--red); }
.b1 { background: var(--blue-bg); color: var(--blue); }
.b2 { background: var(--green-bg); color: var(--green); }
.b-active { background: var(--green-bg); color: var(--green); }
.b-closed { background: #e8ecf2; color: var(--ink-3); }
.status-badge {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 64px; min-height: 30px;
  border-radius: 999px; cursor: pointer; user-select: none;
  font-size: 12px; font-weight: 700;
}
.status-badge:active { transform: scale(.95); }
@media (min-width: 768px) { .status-badge:hover { filter: brightness(.95); } }

/* ---------------- 提示 ---------------- */
.flash {
  padding: 11px 14px; border-radius: 10px; margin: 10px 0;
  font-size: 14px;
}
.flash.error { background: var(--red-bg); color: var(--red); }
.flash.info { background: var(--blue-bg); color: var(--blue); }
.flash.warn { background: var(--orange-bg); color: var(--orange); }

/* ---------------- 标签 ---------------- */
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
.chip {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--bg); border: 1px solid var(--line); border-radius: 999px;
  padding: 5px 12px; font-size: 13px;
}
.chip-red { background: var(--red-bg); color: var(--red); border-color: #fecaca; }
.chip-x {
  border: none; background: transparent; color: var(--ink-3); cursor: pointer;
  font-size: 15px; padding: 0 2px; line-height: 1;
}
.chip-x:hover { color: var(--red); }

/* ---------------- 页头 ---------------- */
.page-head { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px; }
.page-head h1 { margin: 14px 0 6px; }
.page-head-actions { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }

/* 作业信息 */
.assign-info { display: flex; flex-direction: column; gap: 12px; }
.assign-info h2 { margin: 0 0 4px; font-size: 17px; }
.assign-meta { font-size: 13px; color: var(--ink-2); }
.stats-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; }
.stat-chip {
  background: var(--bg); border-radius: 12px; padding: 9px 4px; text-align: center;
}
.stat-chip b { font-size: 19px; display: block; line-height: 1.35; }
.stat-chip span { font-size: 11px; color: var(--ink-3); }
.stat-chip.miss b { color: var(--red); }
@media (min-width: 768px) {
  .assign-info { flex-direction: row; justify-content: space-between; align-items: center; }
  .stats-row { gap: 12px; }
}

/* 扫码面板(移动端吸顶, 保证扫码按钮随时可点) */
.scan-panel {
  border: 1.5px solid #c7d2fe;
  position: sticky; top: calc(var(--topbar-h) + 6px); z-index: 30;
}
@media (min-width: 768px) { .scan-panel { position: static; } }
.feed { list-style: none; margin: 8px 0 0; padding: 0; max-height: 190px; overflow-y: auto; }
.feed-item { padding: 7px 12px; border-radius: 8px; margin: 5px 0; font-size: 13px; }
.toast-green { background: var(--green-bg); color: var(--green); }
.toast-yellow { background: var(--orange-bg); color: var(--orange); }
.toast-orange { background: #ffedd5; color: #c2410c; }
.toast-red { background: var(--red-bg); color: var(--red); }

/* ---------------- 扫码浮层 ---------------- */
.scan-overlay {
  position: fixed; inset: 0; z-index: 1000;
  background: rgba(2, 6, 23, .96);
  display: flex; align-items: center; justify-content: center; padding: 14px;
}
.scan-box {
  width: 100%; max-width: 520px; position: relative;
  background: #000; border-radius: 18px; overflow: hidden;
  box-shadow: 0 24px 80px rgba(0, 0, 0, .55);
}
.scan-head {
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 14px; background: #0f172a; color: #fff;
}
.scan-title { font-size: 15px; font-weight: 600; display: flex; align-items: center; gap: 7px; }
.scan-stage { position: relative; }
.scan-box video { display: block; width: 100%; max-height: 66vh; background: #000; }
.scan-frame {
  position: absolute; left: 11%; right: 11%; top: 13%; bottom: 16%;
  border: 2.5px solid rgba(255, 255, 255, .9);
  border-radius: 18px;
  box-shadow: 0 0 0 9999px rgba(2, 6, 23, .32);
  pointer-events: none;
}
.scan-line {
  position: absolute; left: 12%; right: 12%; height: 2.5px;
  background: linear-gradient(90deg, transparent, #34d399, transparent);
  border-radius: 2px;
  animation: scanmove 2.2s ease-in-out infinite;
  pointer-events: none;
}
@keyframes scanmove {
  0% { top: 15%; } 50% { top: 80%; } 100% { top: 15%; }
}
.scan-status {
  padding: 11px 14px; background: #0f172a; color: #cbd5e1;
  font-size: 13px; text-align: center; line-height: 1.6;
}
.scan-box .btn-ghost { color: #cbd5e1; }
.scan-box .btn-ghost:hover { color: #fff; background: rgba(255,255,255,.08); }

/* 全屏扫码反馈 */
.scan-flash {
  position: fixed; top: 50%; left: 50%; transform: translate(-50%, -50%);
  z-index: 2000;
  padding: 18px 30px; border-radius: 16px;
  font-size: 20px; font-weight: 800; text-align: center;
  max-width: 86vw;
  box-shadow: 0 16px 50px rgba(0, 0, 0, .35);
  animation: pop .16s ease-out;
}
@keyframes pop { from { transform: translate(-50%, -50%) scale(.82); opacity: .3; } }

/* ---------------- 进度条 ---------------- */
.progress { background: #e6eaf1; border-radius: 999px; height: 8px; margin: 8px 0; overflow: hidden; }
.progress-bar { background: var(--green); height: 100%; border-radius: 999px; transition: width .3s; }
.bar-warn { background: var(--orange); }
.small-bar { height: 6px; display: inline-block; width: 110px; vertical-align: middle; margin-right: 8px; }

/* ---------------- 标签页(报表) ---------------- */
.tabs {
  position: sticky; top: var(--topbar-h); z-index: 40;
  display: flex; gap: 6px; padding: 10px 0;
  background: var(--bg);
}
.tab {
  flex: 1; text-align: center;
  padding: 10px 4px;
  background: #fff; border: 1px solid var(--line); border-radius: 10px;
  color: var(--ink-2); font-size: 13px; font-weight: 500;
}
.tab.active { background: var(--primary); border-color: var(--primary); color: #fff; font-weight: 700; }

/* ---------------- 登录页 ---------------- */
.login-hero {
  min-height: calc(100dvh - var(--topbar-h));
  display: flex; align-items: center; justify-content: center;
  padding: 22px 16px 60px;
  background: radial-gradient(120% 90% at 15% 0%, #6366f1 0%, #4f46e5 38%, #7c3aed 75%, #6d28d9 100%);
}
.login-card {
  width: 100%; max-width: 380px;
  background: #fff; border-radius: 20px; padding: 30px 24px 22px;
  box-shadow: 0 24px 70px rgba(15, 23, 42, .35);
}
.login-logo {
  width: 54px; height: 54px; margin: 0 auto 12px;
  border-radius: 15px;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  display: flex; align-items: center; justify-content: center; color: #fff;
  box-shadow: 0 8px 20px rgba(99, 102, 241, .4);
}
.login-logo .ic { width: 28px; height: 28px; }
.login-title { text-align: center; font-size: 22px; margin: 0 0 4px; }
.login-sub { text-align: center; color: var(--ink-3); font-size: 13px; margin: 0 0 20px; }
.login-card form { display: grid; gap: 10px; }
.login-foot { text-align: center; color: var(--ink-3); font-size: 12px; margin: 16px 0 0; }

/* 访客搜索 */
.guest-hero { background: linear-gradient(135deg, #4f46e5, #7c3aed); border: none; }
.guest-hero h2 { color: #fff; margin: 0 0 4px; }
.guest-hero p { color: rgba(255, 255, 255, .85); margin: 0 0 12px; font-size: 13px; }
.search-row { display: grid; gap: 8px; }
@media (min-width: 620px) { .search-row { grid-template-columns: 1fr auto; } }
.search-row input { border-radius: 12px; }
.guest-hero .guest-scan {
  margin-top: 8px; width: 100%;
  background: rgba(255, 255, 255, .16); border-color: rgba(255, 255, 255, .45); color: #fff;
}
.guest-hero .guest-scan:hover { background: rgba(255, 255, 255, .26); color: #fff; }

/* ---------------- 其他 ---------------- */
.missing summary { cursor: pointer; color: var(--red); font-size: 13px; font-weight: 700; }
.missing-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
.ok-text { color: var(--green); font-weight: 700; }
.brand-line { display: flex; align-items: center; gap: 8px; margin: 4px 0 10px; }
.brand-line h1 { margin: 0; }
@media (max-width: 767.98px) { .hide-m { display: none !important; } }

/* ---------------- 状态选择遮罩 ---------------- */
.status-mask {
  position: fixed; inset: 0; z-index: 120;
  background: rgba(15, 23, 42, .45);
  display: flex; align-items: flex-end; justify-content: center;
  animation: maskIn .18s ease;
}
@keyframes maskIn { from { opacity: 0; } }
.status-sheet {
  width: 100%; max-width: 420px;
  background: #fff; border-radius: 18px 18px 0 0;
  padding: 18px 16px calc(14px + env(safe-area-inset-bottom));
  animation: sheetUp .2s ease;
}
@keyframes sheetUp { from { transform: translateY(30px); opacity: .6; } }
@media (min-width: 768px) {
  .status-mask { align-items: center; }
  .status-sheet { border-radius: 18px; padding: 20px; animation: maskIn .18s ease; }
}
.sheet-head h4 { margin: 0; font-size: 17px; }
.sheet-sub { margin: 4px 0 0; font-size: 13px; color: var(--ink-3); }
.sheet-opts { margin: 14px 0 10px; display: grid; gap: 8px; }
.status-opt {
  display: flex; align-items: center; gap: 10px;
  width: 100%; padding: 11px 14px;
  border: 1px solid var(--line); border-radius: 12px;
  background: #fff; font-size: 14px; color: var(--ink);
  cursor: pointer; -webkit-tap-highlight-color: transparent;
}
.status-opt .status-badge { pointer-events: none; }
.status-opt .opt-label { flex: 1; text-align: left; }
.status-opt .opt-mark { font-size: 12px; color: var(--primary); font-weight: 700; }
.status-opt.active { border-color: var(--primary); background: var(--primary-100); }
.status-opt:active { transform: scale(.98); }
.sheet-cancel { width: 100%; }