/* ============ 结伴同行 · 英语学习打卡 ============ */
:root {
  --primary: #10B981;
  --primary-dark: #059669;
  --primary-light: #D1FAE5;
  --accent: #F59E0B;
  --bg: #F3F4F6;
  --card: #FFFFFF;
  --text: #1F2937;
  --text-sub: #6B7280;
  --border: #E5E7EB;
  --danger: #EF4444;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
}

#app {
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
}

.hidden { display: none !important; }

/* ============ 顶部栏 ============ */
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  background: var(--card);
  border-bottom: 1px solid var(--border);
}
.topbar-left {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 17px;
  font-weight: 600;
}
.topbar-right { font-size: 14px; color: var(--text-sub); }

/* ============ 页面容器 ============ */
.page {
  flex: 1;
  padding: 16px 16px 84px;
}

.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
  margin-bottom: 14px;
}

.section-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 14px;
  color: var(--text);
}

/* ============ 底部导航 ============ */
.tabbar {
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: 480px;
  display: flex;
  background: var(--card);
  border-top: 1px solid var(--border);
  z-index: 30;
  padding-bottom: env(safe-area-inset-bottom);
}
.tab-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 8px 0;
  font-size: 11px;
  color: var(--text-sub);
  text-decoration: none;
}
.tab-item .tab-icon { font-size: 22px; }
.tab-item.active { color: var(--primary); font-weight: 600; }

/* ============ 登录页 ============ */
.login-card {
  padding-top: 12vh;
  text-align: center;
}
.login-logo { font-size: 56px; margin-bottom: 12px; }
.login-card h1 { font-size: 24px; margin-bottom: 8px; }
.login-sub { color: var(--text-sub); font-size: 14px; margin-bottom: 32px; }

.input-wrap { margin-bottom: 14px; text-align: left; }
.input-label {
  display: block;
  font-size: 13px;
  color: var(--text-sub);
  margin-bottom: 6px;
}
.input {
  width: 100%;
  padding: 13px 14px;
  border: 1.5px solid var(--border);
  border-radius: 10px;
  font-size: 16px;
  background: var(--card);
  color: var(--text);
  outline: none;
  transition: border-color .2s;
}
.input:focus { border-color: var(--primary); }
textarea.input { resize: none; min-height: 72px; }

/* ============ 按钮 ============ */
.btn-primary {
  width: 100%;
  padding: 14px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background .2s;
}
.btn-primary:active { background: var(--primary-dark); }
.btn-primary:disabled { opacity: .6; cursor: not-allowed; }

.btn-ghost {
  width: 100%;
  padding: 12px;
  background: transparent;
  color: var(--text-sub);
  border: 1.5px solid var(--border);
  border-radius: 10px;
  font-size: 15px;
  cursor: pointer;
}

.link-btn {
  display: inline-block;
  margin-top: 18px;
  color: var(--text-sub);
  font-size: 13px;
  text-decoration: underline;
  background: none;
  border: none;
  cursor: pointer;
}

/* ============ 打卡首页 ============ */
.date-line {
  text-align: center;
  color: var(--text-sub);
  font-size: 14px;
  margin-bottom: 14px;
}
.checkin-hero {
  text-align: center;
  padding: 26px 18px;
}
.streak-flame { font-size: 40px; }
.streak-num {
  font-size: 52px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.1;
}
.streak-num .streak-unit { font-size: 18px; color: var(--text-sub); font-weight: 500; margin-left: 2px; }
.streak-label { color: var(--text-sub); font-size: 14px; margin-top: 4px; }

.done-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--primary-light);
  color: var(--primary-dark);
  padding: 10px 22px;
  border-radius: 999px;
  font-size: 16px;
  font-weight: 600;
  margin-top: 14px;
}

.stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 14px;
}
.stat-item {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 14px 8px;
  text-align: center;
}
.stat-num { font-size: 22px; font-weight: 700; color: var(--text); }
.stat-label { font-size: 12px; color: var(--text-sub); margin-top: 3px; }

/* ============ 成员列表 ============ */
.member-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}
.member-item:last-child { border-bottom: none; }
.avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 17px;
  font-weight: 600;
  flex-shrink: 0;
}
.member-info { flex: 1; min-width: 0; }
.member-name { font-size: 15px; font-weight: 600; }
.member-note {
  font-size: 13px;
  color: var(--text-sub);
  margin-top: 2px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.member-status {
  flex-shrink: 0;
  font-size: 13px;
  font-weight: 600;
}
.member-status.done { color: var(--primary); }
.member-status.pending { color: #9CA3AF; }

/* ============ 进度条 ============ */
.progress-wrap { margin: 8px 0 4px; }
.progress-bar {
  height: 8px;
  background: var(--border);
  border-radius: 999px;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 999px;
  transition: width .4s ease;
}
.progress-text {
  font-size: 13px;
  color: var(--text-sub);
  margin-top: 6px;
  display: flex;
  justify-content: space-between;
}

/* ============ 小组卡片（可展开） ============ */
.group-card { cursor: pointer; }
.group-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}
.group-name { font-size: 16px; font-weight: 600; }
.group-count { font-size: 13px; color: var(--text-sub); flex-shrink: 0; }
.expand-arrow {
  transition: transform .2s;
  color: var(--text-sub);
  flex-shrink: 0;
}
.group-card.expanded .expand-arrow { transform: rotate(180deg); }
.group-card-detail { margin-top: 12px; border-top: 1px dashed var(--border); padding-top: 4px; }

/* ============ 统计排行 ============ */
.rank-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}
.rank-row:last-child { border-bottom: none; }
.rank-badge {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 700;
  background: var(--bg);
  color: var(--text-sub);
  flex-shrink: 0;
}
.rank-badge.r1 { background: #FEF3C7; color: #D97706; }
.rank-badge.r2 { background: #F1F5F9; color: #64748B; }
.rank-badge.r3 { background: #FDE8D8; color: #C2560C; }
.rate-num { font-weight: 700; color: var(--primary-dark); font-size: 15px; flex-shrink: 0; }
.rate-detail { font-size: 12px; color: var(--text-sub); margin-top: 2px; }

.seg-tabs {
  display: flex;
  background: var(--border);
  border-radius: 10px;
  padding: 3px;
  margin-bottom: 14px;
}
.seg-tab {
  flex: 1;
  padding: 8px;
  text-align: center;
  font-size: 14px;
  color: var(--text-sub);
  border-radius: 8px;
  cursor: pointer;
  border: none;
  background: transparent;
}
.seg-tab.active {
  background: var(--card);
  color: var(--text);
  font-weight: 600;
  box-shadow: var(--shadow);
}

/* ============ 管理后台 ============ */
.admin-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 11px 0;
  border-bottom: 1px solid var(--border);
}
.admin-row:last-child { border-bottom: none; }
.admin-row-name { flex: 1; font-size: 15px; }
.admin-row-sub { font-size: 12px; color: var(--text-sub); }
.mini-btn {
  padding: 6px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--card);
  font-size: 13px;
  color: var(--text);
  cursor: pointer;
}
.mini-btn.danger { color: var(--danger); border-color: #FECACA; }
.mini-btn.primary { color: var(--primary-dark); border-color: var(--primary-light); background: var(--primary-light); }

.form-row { display: flex; gap: 10px; margin-bottom: 12px; }
.form-row .input { flex: 1; }

/* ============ Toast ============ */
.toast {
  position: fixed;
  top: 70px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(31, 41, 55, .92);
  color: #fff;
  padding: 10px 20px;
  border-radius: 999px;
  font-size: 14px;
  z-index: 100;
  max-width: 86%;
  text-align: center;
}
.toast.error { background: rgba(239, 68, 68, .95); }
.toast.success { background: rgba(16, 185, 129, .95); }

/* ============ 空状态 ============ */
.empty {
  text-align: center;
  padding: 40px 0;
  color: var(--text-sub);
  font-size: 14px;
}
.empty-icon { font-size: 40px; margin-bottom: 10px; }

/* ============ 加载 ============ */
.loading {
  text-align: center;
  padding: 40px 0;
  color: var(--text-sub);
  font-size: 14px;
}