*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0.05);
}

a,
button,
select,
[role="button"],
label[for],
input[type="checkbox"],
input[type="radio"],
input[type="submit"],
summary,
.btn,
.btn-link,
.tab {
  cursor: pointer !important;
}

button:disabled,
.btn:disabled,
a[disabled] {
  cursor: not-allowed !important;
}

:root {
  --bg: #fafafa;
  --surface: #ffffff;
  --border: #e5e7eb;
  --text: #111827;
  --text-secondary: #6b7280;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --success: #059669;
  --success-bg: #ecfdf5;
  --warning: #d97706;
  --warning-bg: #fffbeb;
  --error: #dc2626;
  --error-bg: #fef2f2;
  --radius: 8px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --mono: "SF Mono", "Fira Code", "Fira Mono", monospace;
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  min-height: 100vh;
  padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}

/* Nav */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-brand {
  font-weight: 700;
  font-size: 18px;
  color: var(--text);
  text-decoration: none;
}

.nav-tag {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--success);
  background: var(--success-bg);
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 14px;
}

.nav-right a {
  color: var(--text-secondary);
  text-decoration: none;
}

.nav-right a:hover {
  color: var(--text);
}

#userEmail {
  color: var(--text-secondary);
  font-size: 13px;
}

/* Layout */
.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 32px 24px;
}

.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

.page-header h1 {
  font-size: 22px;
  font-weight: 700;
}

/* Cards */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  margin-bottom: 20px;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.card h2 {
  font-size: 18px;
  font-weight: 600;
}

/* Forms */
.form-group {
  margin-bottom: 16px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 4px;
  color: var(--text);
}

.form-group .hint {
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 2px;
}

.form-group .hint a {
  cursor: pointer;
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="date"],
textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-family: var(--font);
  font-size: 14px;
  outline: none;
  transition: border-color 0.15s;
}

input:focus,
textarea:focus {
  border-color: var(--primary);
}

textarea {
  resize: vertical;
  min-height: 60px;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 10px 18px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: background-color 0.15s;
}

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

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

.btn-primary:active {
  transform: scale(0.98);
  opacity: 0.9;
}

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

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

.btn-secondary:active {
  transform: scale(0.98);
}

.btn-danger {
  background: var(--error);
  color: white;
}

.btn-danger:active {
  transform: scale(0.98);
  opacity: 0.9;
}

.btn-small {
  padding: 6px 12px;
  font-size: 13px;
}

.btn-link {
  background: none;
  color: var(--primary);
  padding: 0;
  border: none;
  font-size: 13px;
  cursor: pointer;
}

.btn-link:hover {
  text-decoration: underline;
}

.btn-link:active {
  opacity: 0.7;
}

a:active {
  opacity: 0.85;
}

/* Errors */
.error-message {
  background: var(--error-bg);
  color: var(--error);
  padding: 10px 14px;
  border-radius: 6px;
  font-size: 14px;
  display: none;
  margin-bottom: 16px;
}

.success-message {
  background: var(--success-bg);
  color: var(--success);
  padding: 10px 14px;
  border-radius: 6px;
  font-size: 14px;
  display: none;
  margin-bottom: 16px;
}

/* Table */
.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th, td {
  padding: 10px 12px;
  text-align: left;
  font-size: 14px;
  border-bottom: 1px solid var(--border);
}

th {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  font-weight: 600;
}

/* Badges */
.badge {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 3px 8px;
  border-radius: 4px;
}

.badge-open { background: var(--warning-bg); color: var(--warning); }
.badge-paid { background: var(--success-bg); color: var(--success); }
.badge-void { background: var(--error-bg); color: var(--error); }
.badge-expired { background: #f3f4f6; color: var(--text-secondary); }
.badge-verified { background: var(--success-bg); color: var(--success); }
.badge-unverified { background: #f3f4f6; color: var(--text-secondary); }

/* Auth page */
.auth-container {
  max-width: 400px;
  margin: 80px auto;
  padding: 0 24px;
}

.auth-container h1 {
  font-size: 24px;
  margin-bottom: 8px;
}

.auth-container p {
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.auth-toggle {
  text-align: center;
  margin-top: 16px;
  font-size: 14px;
  color: var(--text-secondary);
}

.auth-toggle a {
  color: var(--primary);
}

/* Empty state */
.empty {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-secondary);
}

.empty p {
  margin-bottom: 16px;
}

/* Line items */
.line-items-list {
  border: 1px solid var(--border);
  border-radius: 6px;
  margin-bottom: 8px;
}

.line-item-row {
  display: grid;
  grid-template-columns: 1fr 80px 120px 40px;
  gap: 8px;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  align-items: center;
}

.line-item-row:last-child {
  border-bottom: none;
}

.line-item-row input {
  width: 100%;
}

/* Copy field */
.copy-field {
  display: flex;
  gap: 8px;
  align-items: center;
}

.copy-field input {
  flex: 1;
  font-family: var(--mono);
  font-size: 13px;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0;
  border-bottom: 2px solid var(--border);
  margin-bottom: 24px;
}

.tab {
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  background: none;
  border-top: none;
  border-left: none;
  border-right: none;
}

.tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

/* Wallet card */
.wallet-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}

.wallet-item:last-child {
  border-bottom: none;
}

.wallet-address {
  font-family: var(--mono);
  font-size: 13px;
}

/* Toast notifications */
.toast-container {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 9000;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  padding: 12px 18px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  max-width: 380px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
  cursor: pointer;
  pointer-events: auto;
  opacity: 0;
  transform: translateX(20px);
  transition: opacity 0.2s, transform 0.2s;
}

.toast-visible {
  opacity: 1;
  transform: translateX(0);
}

.toast-exit {
  opacity: 0;
  transform: translateX(20px);
}

.toast-error {
  background: var(--error-bg);
  color: var(--error);
  border: 1px solid var(--error);
}

.toast-success {
  background: var(--success-bg);
  color: var(--success);
  border: 1px solid var(--success);
}

.toast-info {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
}

/* Confirm modal */
.confirm-overlay {
  position: fixed;
  inset: 0;
  z-index: 9500;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0);
  transition: background 0.15s;
}

.confirm-visible {
  background: rgba(0, 0, 0, 0.35);
}

.confirm-dialog {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  max-width: 400px;
  width: 90%;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.confirm-message {
  font-size: 15px;
  line-height: 1.5;
  margin-bottom: 20px;
  color: var(--text);
}

.confirm-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
}

/* Responsive */
@media (max-width: 600px) {
  .container { padding: 20px 16px; }
  .page-header { flex-direction: column; align-items: flex-start; gap: 12px; }
  .line-item-row { grid-template-columns: 1fr; }
  .tabs {
    overflow-x: auto;
    flex-wrap: nowrap;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  .tabs::-webkit-scrollbar { display: none; }
  .tab {
    padding: 8px 12px;
    font-size: 13px;
    white-space: nowrap;
    flex-shrink: 0;
  }
  .wallet-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }
  .wallet-address {
    font-size: 11px;
    word-break: break-all;
  }
}

/* Touch device targets */
@media (any-pointer: coarse) {
  .btn-small { min-height: 44px; padding: 12px 16px; display: inline-flex; align-items: center; justify-content: center; }
  .btn-link { min-height: 44px; display: inline-flex; align-items: center; }
  .tab { min-height: 44px; }
  .nav-right a { min-height: 44px; display: inline-flex; align-items: center; }
  select { min-height: 44px; }
}