/* 表格转换器 - 全局样式 */
:root {
  --bg: #f5f5f7;
  --surface: #ffffff;
  --border: #e0e0e0;
  --text: #1a1a1a;
  --text2: #555555;
  --text3: #999999;
  --accent: #1a1a1a;
  --accent-light: #f0f0f0;
  --success: #16a34a;
  --warn: #ca8a04;
  --danger: #dc2626;
  --radius: 10px;
  --shadow: 0 2px 8px rgba(0,0,0,0.06);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}
.container { max-width: 1100px; margin: 0 auto; padding: 20px; }

/* Header */
.header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 24px; background: var(--surface); border-bottom: 1px solid var(--border);
  margin: -20px -20px 24px -20px; flex-wrap: wrap; gap: 10px;
}
.header h1 { font-size: 18px; font-weight: 700; }

/* Nav menu */
.nav-menu { display: flex; gap: 4px; }
.nav-menu a {
  padding: 6px 16px; border-radius: 6px; font-size: 13px; color: var(--text2);
  text-decoration: none; transition: all 0.2s;
}
.nav-menu a:hover { background: var(--accent-light); color: var(--text); }
.nav-menu a.active { background: var(--accent); color: #fff; }

.header .user { font-size: 13px; color: var(--text2); display: flex; align-items: center; gap: 10px; }
.header .user button {
  padding: 4px 12px; border-radius: 6px; border: 1px solid var(--border);
  background: transparent; cursor: pointer; font-size: 12px;
}
.header .user button:hover { border-color: var(--accent); }

/* Step bar */
.step-bar { display: flex; gap: 8px; margin-bottom: 24px; }
.step {
  flex: 1; padding: 12px 8px; border-radius: var(--radius);
  border: 1px solid var(--border); text-align: center; font-size: 13px;
  font-weight: 500; color: var(--text3); background: var(--surface);
  transition: all 0.3s; cursor: default; position: relative;
}
.step.active { border-color: var(--accent); color: var(--text); font-weight: 600; }
.step.done { border-color: var(--success); color: var(--success); }
.step::after {
  content: attr(data-num); position: absolute; top: -8px; left: 50%; transform: translateX(-50%);
  width: 20px; height: 20px; border-radius: 50%; background: var(--border);
  color: #fff; font-size: 11px; line-height: 20px; font-weight: 700;
}
.step.active::after { background: var(--accent); }
.step.done::after { background: var(--success); }

/* Panel */
.panel {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 24px; margin-bottom: 16px;
  box-shadow: var(--shadow);
}
.panel-title { font-size: 15px; font-weight: 600; margin-bottom: 16px; display: flex; align-items: center; gap: 8px; }

/* Upload */
.upload-zone {
  border: 2px dashed var(--border); border-radius: var(--radius);
  padding: 48px 24px; text-align: center; cursor: pointer;
  transition: all 0.2s; background: var(--bg);
}
.upload-zone:hover { border-color: var(--accent); background: #f0f0f2; }
.upload-zone.dragover { border-color: var(--accent); background: #ebebed; }
.upload-zone .icon { font-size: 40px; margin-bottom: 12px; }
.upload-zone p { color: var(--text2); font-size: 14px; }
.upload-zone .hint { color: var(--text3); font-size: 12px; margin-top: 8px; }
input[type="file"] { display: none; }

/* Tables */
.data-table { width: 100%; border-collapse: collapse; font-size: 12px; }
.data-table th, .data-table td {
  border: 1px solid var(--border); padding: 7px 10px; text-align: left;
  white-space: nowrap;
}
.data-table th { background: #f5f5f5; font-weight: 600; position: sticky; top: 0; z-index: 1; }
.data-table tr:nth-child(even) td { background: #fafafa; }
.table-wrap { max-height: 360px; overflow: auto; border-radius: var(--radius); border: 1px solid var(--border); }

/* Sheet tabs */
.sheet-tabs { display: flex; gap: 6px; margin-bottom: 14px; flex-wrap: wrap; }
.sheet-tab {
  padding: 6px 16px; border-radius: 6px; border: 1px solid var(--border);
  background: var(--surface); cursor: pointer; font-size: 12px; transition: all 0.2s;
}
.sheet-tab:hover { border-color: var(--accent); }
.sheet-tab.active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* Mapping */
.mapping-grid { display: grid; grid-template-columns: 110px 30px 1fr 90px; gap: 10px 12px; align-items: center; }
.mapping-label { font-size: 13px; font-weight: 600; text-align: right; }
.mapping-arrow { text-align: center; color: var(--text3); font-size: 16px; }
.mapping-select {
  padding: 8px 12px; border-radius: 8px; border: 1px solid var(--border);
  font-size: 13px; background: var(--surface); width: 100%; cursor: pointer;
}
.mapping-select:focus { outline: none; border-color: var(--accent); }
.mapping-select.matched { border-color: var(--success); background: #f0fdf4; }
.mapping-select.manual { border-color: var(--warn); background: #fefce8; }
.mapping-select.missing { border-color: var(--danger); background: #fef2f2; }
.mapping-score { font-size: 11px; text-align: center; }
.mapping-score .tag {
  display: inline-block; padding: 2px 10px; border-radius: 10px; font-size: 11px; font-weight: 500;
}
.tag-high { background: #dcfce7; color: var(--success); }
.tag-med { background: #fef9c3; color: var(--warn); }
.tag-low { background: #fee2e2; color: var(--danger); }

/* Buttons */
.btn {
  padding: 9px 22px; border-radius: 8px; border: 1px solid var(--border);
  background: var(--surface); cursor: pointer; font-size: 13px; font-weight: 500;
  transition: all 0.2s;
}
.btn:hover { border-color: var(--accent); }
.btn-primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn-primary:hover { opacity: 0.88; }
.btn-success { background: var(--success); color: #fff; border-color: var(--success); }
.btn-success:hover { opacity: 0.88; }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.action-bar { display: flex; gap: 10px; justify-content: flex-end; margin-top: 18px; }

/* Stats */
.stats-row { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 16px; }
.stat-box {
  text-align: center; min-width: 100px; padding: 14px 18px;
  border-radius: var(--radius); background: var(--bg); border: 1px solid var(--border);
}
.stat-box .num { font-size: 28px; font-weight: 700; }
.stat-box .label { font-size: 12px; color: var(--text3); margin-top: 2px; }

/* Alerts */
.alert { padding: 10px 14px; border-radius: 8px; font-size: 13px; margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
.alert-info { background: #eff6ff; border: 1px solid #bfdbfe; color: #1e40af; }
.alert-warn { background: #fefce8; border: 1px solid #fde047; color: #854d0e; }
.alert-error { background: #fef2f2; border: 1px solid #fecaca; color: #991b1b; }
.alert-success { background: #f0fdf4; border: 1px solid #86efac; color: #166534; }

/* Badge */
.badge { display: inline-block; padding: 2px 8px; border-radius: 10px; font-size: 11px; font-weight: 500; }
.badge-success { background: #dcfce7; color: var(--success); }
.badge-warn { background: #fef9c3; color: var(--warn); }
.badge-error { background: #fee2e2; color: var(--danger); }

/* Footer */
.page-footer, .login-footer {
  text-align: center; padding: 20px 0; font-size: 12px; color: var(--text3);
}
.page-footer a, .login-footer a { color: var(--text3); text-decoration: none; }
.page-footer a:hover, .login-footer a:hover { color: var(--text2); text-decoration: underline; }
.login-footer { position: fixed; bottom: 0; left: 0; right: 0; }

/* Login page */
.login-body { display: flex; align-items: center; justify-content: center; min-height: 100vh; flex-direction: column; }
.login-box {
  width: 100%; max-width: 380px; padding: 40px 32px;
  background: var(--surface); border-radius: var(--radius);
  border: 1px solid var(--border); box-shadow: var(--shadow);
}
.login-box h2 { font-size: 20px; margin-bottom: 6px; text-align: center; }
.login-box .sub { font-size: 13px; color: var(--text3); text-align: center; margin-bottom: 24px; }
.login-box input {
  width: 100%; padding: 11px 14px; border-radius: 8px; border: 1px solid var(--border);
  font-size: 14px; margin-bottom: 14px;
}
.login-box input:focus { outline: none; border-color: var(--accent); }
.login-box button {
  width: 100%; padding: 11px; border-radius: 8px; border: none;
  background: var(--accent); color: #fff; font-size: 14px; font-weight: 600;
  cursor: pointer; transition: opacity 0.2s;
}
.login-box button:hover { opacity: 0.88; }
.login-box .error { color: var(--danger); font-size: 13px; margin-top: 10px; text-align: center; display: none; }

/* ===================== 学生信息页布局 ===================== */
.students-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 16px;
}

.sidebar .panel { padding: 16px; }
.sidebar .form-group { margin-bottom: 12px; }
.sidebar .form-group label {
  display: block; font-size: 12px; font-weight: 600; color: var(--text2); margin-bottom: 4px;
}
.sidebar .form-group select,
.sidebar .form-group input {
  width: 100%; padding: 8px 10px; border-radius: 6px; border: 1px solid var(--border);
  font-size: 13px; background: var(--surface);
}

.source-tabs { display: flex; gap: 4px; margin-bottom: 12px; }
.source-tab {
  flex: 1; padding: 6px 0; border-radius: 6px; border: 1px solid var(--border);
  background: transparent; cursor: pointer; font-size: 12px; text-align: center;
}
.source-tab.active { background: var(--accent); color: #fff; border-color: var(--accent); }

.mini-upload {
  border: 1px dashed var(--border); border-radius: 6px; padding: 16px;
  text-align: center; cursor: pointer; font-size: 12px; color: var(--text2);
  transition: all 0.2s;
}
.mini-upload:hover { border-color: var(--accent); background: var(--bg); }
.hint-text { font-size: 11px; color: var(--text3); margin-top: 6px; }

.mini-stats { display: flex; gap: 8px; }
.mini-stat {
  flex: 1; text-align: center; padding: 10px 4px;
  border-radius: 6px; background: var(--bg); border: 1px solid var(--border);
}
.mini-stat .num { font-size: 20px; font-weight: 700; }
.mini-stat .label { font-size: 11px; color: var(--text3); }

.search-box input {
  padding: 6px 12px; border-radius: 6px; border: 1px solid var(--border);
  font-size: 13px; width: 220px;
}
.search-box input:focus { outline: none; border-color: var(--accent); }

/* ===================== 弹窗 ===================== */
.modal { position: fixed; inset: 0; z-index: 100; display: flex; align-items: center; justify-content: center; }
.modal-overlay { position: absolute; inset: 0; background: rgba(0,0,0,0.4); }
.modal-content {
  position: relative; background: var(--surface); border-radius: var(--radius);
  border: 1px solid var(--border); box-shadow: 0 8px 32px rgba(0,0,0,0.15);
  width: 90%; max-width: 520px; max-height: 80vh; overflow: hidden;
  display: flex; flex-direction: column;
}
.modal-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 20px; border-bottom: 1px solid var(--border);
}
.modal-header h3 { font-size: 15px; }
.modal-close {
  background: none; border: none; font-size: 20px; cursor: pointer; color: var(--text3);
}
.modal-body { padding: 16px 20px; overflow-y: auto; flex: 1; }
.modal-footer {
  display: flex; justify-content: flex-end; gap: 8px;
  padding: 12px 20px; border-top: 1px solid var(--border); background: var(--bg);
}

/* 重名选择列表 */
.dup-list { display: flex; flex-direction: column; gap: 8px; }
.dup-item {
  display: flex; align-items: flex-start; gap: 10px;
  padding: 10px 12px; border-radius: 8px; border: 1px solid var(--border);
  cursor: pointer; transition: all 0.2s;
}
.dup-item:hover { border-color: var(--accent); background: var(--bg); }
.dup-item input { margin-top: 3px; }
.dup-info { flex: 1; }
.dup-name { font-size: 14px; font-weight: 600; }
.dup-no { font-size: 12px; color: var(--text2); font-weight: 400; margin-left: 6px; }
.dup-meta { font-size: 12px; color: var(--text3); margin-top: 2px; }

/* Misc */
.hidden { display: none !important; }
.preview-note { font-size: 12px; color: var(--text3); margin-bottom: 10px; }
.hint-box { font-size: 13px; color: var(--text2); line-height: 1.8; }
.hint-box b { color: var(--text); }

/* Responsive */
@media (max-width: 768px) {
  .students-layout { grid-template-columns: 1fr; }
  .mapping-grid { grid-template-columns: 1fr; gap: 6px; }
  .mapping-label { text-align: left; }
  .mapping-arrow { display: none; }
  .step-bar { flex-wrap: wrap; }
  .step { flex: 1 1 40%; font-size: 11px; padding: 10px 4px; }
  .header { flex-direction: column; gap: 8px; align-items: flex-start; }
  .nav-menu { order: 3; width: 100%; }
  .search-box input { width: 100%; }
}

/* 跳转加载 */
.login-loading {
  text-align: center;
  padding: 60px 40px;
}
.login-loading .icon {
  font-size: 48px;
  margin-bottom: 16px;
  animation: spin 1s linear infinite;
}
.login-loading p {
  color: var(--text2);
  font-size: 14px;
}
@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* 高亮面板 */
.panel-highlight {
  border: 2px solid var(--accent);
  background: linear-gradient(135deg, #fafafa 0%, #f5f5f7 100%);
}
.panel-highlight .panel-title {
  color: var(--accent);
  font-size: 16px;
}

/* 学期选择 */
#syncSemester {
  width: 100%;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  font-size: 14px;
  background: var(--surface);
  margin-bottom: 12px;
}
#syncSemester:focus {
  outline: none;
  border-color: var(--accent);
}

/* 一键同步按钮 */
.btn-sync-all {
  width: 100%;
  padding: 12px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.5px;
}

/* 步骤优化提示 */
.step-hint {
  text-align: center;
  color: var(--text3);
  font-size: 13px;
  margin: -16px 0 16px 0;
}

/* 快速操作栏 */
.quick-actions {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}
.quick-actions .btn {
  flex: 1;
  min-width: 120px;
}