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

:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --success: #16a34a;
  --danger: #dc2626;
  --radius: 10px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "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: 0 20px;
}

/* Header */
.header {
  background: linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
  color: #fff;
  padding: 36px 0 32px;
  text-align: center;
}

.header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.subtitle {
  font-size: 0.95rem;
  opacity: 0.9;
}

.badges {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 14px;
  flex-wrap: wrap;
}

.badges span {
  background: rgba(255, 255, 255, 0.18);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 8px;
  margin: 24px 0 16px;
  background: var(--card);
  padding: 6px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  width: fit-content;
}

.tab {
  padding: 10px 24px;
  border: none;
  background: transparent;
  border-radius: 8px;
  font-size: 0.95rem;
  cursor: pointer;
  color: var(--text-muted);
  font-weight: 500;
  transition: all 0.2s;
}

.tab:hover {
  color: var(--text);
}

.tab.active {
  background: var(--primary);
  color: #fff;
}

/* Panels */
.panel {
  display: none;
}

.panel.active {
  display: block;
}

/* Cards */
.card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 16px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.card h2 {
  font-size: 1.1rem;
  margin-bottom: 16px;
  color: var(--text);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.card-header h2 {
  margin-bottom: 0;
}

.btn-group {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.hint {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.empty-hint {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  padding: 24px 0 8px;
}

/* Form */
.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

label span {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text-muted);
}

input[type="text"],
input[type="month"],
input[type="number"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
  transition: border-color 0.2s;
}

input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

/* Table */
.table-wrap {
  overflow-x: auto;
  margin: 0 -8px;
  padding: 0 8px;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
  min-width: 900px;
}

.data-table th {
  background: #f1f5f9;
  padding: 10px 8px;
  text-align: left;
  font-weight: 600;
  white-space: nowrap;
  border-bottom: 2px solid var(--border);
}

.data-table td {
  padding: 6px 4px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.data-table input {
  width: 100%;
  min-width: 60px;
  padding: 6px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.85rem;
}

.data-table input[name="name"] {
  min-width: 80px;
}

.data-table .calc-cell {
  font-weight: 600;
  color: var(--primary);
  padding-left: 8px;
  white-space: nowrap;
}

.total-row td {
  background: #f8fafc;
  font-size: 0.95rem;
  padding: 12px 8px;
  border-top: 2px solid var(--border);
}

/* Name list for attendance */
.name-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.name-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

.name-row input {
  flex: 1;
  max-width: 300px;
}

/* Buttons */
.btn {
  padding: 8px 16px;
  border: none;
  border-radius: 8px;
  font-size: 0.9rem;
  cursor: pointer;
  font-weight: 500;
  transition: all 0.2s;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-hover);
}

.btn-secondary {
  background: #f1f5f9;
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  background: #e2e8f0;
}

.btn-danger {
  background: transparent;
  color: var(--danger);
  padding: 4px 10px;
  font-size: 0.8rem;
}

.btn-danger:hover {
  background: #fef2f2;
}

.btn-large {
  padding: 14px 32px;
  font-size: 1rem;
}

.actions {
  text-align: center;
  padding: 8px 0 32px;
}

/* Footer */
.footer {
  text-align: center;
  padding: 24px 0;
  color: var(--text-muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}

.footer-note {
  margin-top: 6px;
  font-size: 0.8rem;
  opacity: 0.8;
}

/* Modal */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  padding: 20px;
}

.modal[hidden] {
  display: none !important;
}

.modal-content {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px;
  max-width: 400px;
  width: 100%;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.modal-content h3 {
  margin-bottom: 12px;
}

.modal-content p {
  margin-bottom: 12px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.modal-content ul {
  margin: 0 0 20px 20px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.modal-content .btn {
  width: 100%;
}

.upgrade-box {
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  margin-bottom: 16px;
}

.upgrade-price {
  font-size: 1rem;
  margin-bottom: 6px;
}

.upgrade-features {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.upgrade-contact {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.upgrade-contact code {
  background: #e2e8f0;
  padding: 1px 5px;
  border-radius: 4px;
  font-size: 0.75rem;
}

.activate-form {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

.activate-form input {
  flex: 1;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
}

.activate-form .btn {
  white-space: nowrap;
}

.activate-error {
  color: var(--danger);
  font-size: 0.85rem;
  margin-top: 8px;
}

.btn-block {
  width: 100%;
  margin-top: 12px;
}

.link-upgrade {
  color: var(--primary);
  background: none;
  border: none;
  padding: 0;
  margin-left: 4px;
  font-size: inherit;
  font-family: inherit;
  cursor: pointer;
  text-decoration: underline;
}

.link-upgrade:hover {
  color: var(--primary-hover);
}

.btn-outline {
  background: #fff;
  color: var(--primary);
  border: 2px solid var(--primary);
  margin-top: 12px;
}

.btn-outline:hover {
  background: #eff6ff;
}

.actions .btn-outline[hidden] {
  display: none;
}

.pro-badge {
  display: inline-block;
  margin-top: 12px;
  background: #fbbf24;
  color: #78350f;
  padding: 4px 14px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
}

/* Toast */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background: #1e293b;
  color: #fff;
  padding: 12px 24px;
  border-radius: 8px;
  font-size: 0.9rem;
  z-index: 200;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  max-width: 90%;
  text-align: center;
}

.toast[hidden] {
  display: none !important;
}

.toast-success {
  background: #16a34a;
}

.toast-error {
  background: #dc2626;
}

/* Responsive */
@media (max-width: 640px) {
  .header h1 {
    font-size: 1.4rem;
  }

  .card {
    padding: 16px;
  }

  .tabs {
    width: 100%;
  }

  .tab {
    flex: 1;
    text-align: center;
    padding: 10px 12px;
  }

  .card-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .btn-group {
    width: 100%;
  }

  .btn-group .btn {
    flex: 1;
    min-width: 0;
    font-size: 0.8rem;
    padding: 8px 10px;
  }
}