/* ============================================================
   TSF ADMIN — Desktop-first stylesheet
   ============================================================ */

:root {
  --bg-page: #0E0E10;
  --bg-surface: #17171A;
  --bg-surface-2: #1E1E22;
  --bg-elevated: #232328;
  --text-primary: #F5F4F1;
  --text-secondary: #A6A5A1;
  --text-muted: #6B6A67;
  --line-subtle: rgba(245, 244, 241, 0.06);
  --line-default: rgba(245, 244, 241, 0.10);
  --line-strong: rgba(245, 244, 241, 0.20);
  --red-core: #C81E1E;
  --red-hover: #A31515;
  --red-tint: rgba(200, 30, 30, 0.10);
  --green-attend: #4FA968;
  --amber: #C79A3C;
  --font-display: 'Instrument Serif', Georgia, serif;
  --font-sans: 'Inter Tight', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', Menlo, monospace;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --dur-fast: 180ms;
  --dur-base: 300ms;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --sidebar-width: 240px;
  color-scheme: dark;
}

[data-theme="light"] {
  --bg-page: #F5F4F1;
  --bg-surface: #FFFFFF;
  --bg-surface-2: #EFEEEB;
  --bg-elevated: #FFFFFF;
  --text-primary: #1A1A1A;
  --text-secondary: #5C5B58;
  --text-muted: #8E8D89;
  --line-subtle: rgba(26, 26, 26, 0.06);
  --line-default: rgba(26, 26, 26, 0.12);
  --line-strong: rgba(26, 26, 26, 0.24);
  --red-tint: rgba(200, 30, 30, 0.08);
  color-scheme: light;
}

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

html, body {
  height: 100%;
  background: var(--bg-page);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
}

img { display: block; max-width: 100%; height: auto; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
input, select, textarea { font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }

:focus-visible {
  outline: 2px solid var(--red-core);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

::selection { background: var(--red-core); color: #FFFFFF; }

/* ---------- Typography ---------- */
h1 {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 400;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

h2 {
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--text-primary);
}

.subtitle {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-top: 2px;
}

.stat-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* ============================================================
   LOGIN
   ============================================================ */

.view { display: none; }
.view.active { display: flex; }

#login-view.active {
  min-height: 100vh;
  align-items: center;
  justify-content: center;
  padding: var(--space-5);
}

.login-card {
  background: var(--bg-surface);
  border: 1px solid var(--line-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  width: 100%;
  max-width: 400px;
  text-align: center;
}

.login-logo {
  height: 40px;
  margin: 0 auto var(--space-5);
}

.login-card h1 { margin-bottom: var(--space-2); }
.login-card .subtitle { margin-bottom: var(--space-6); }

.form-group {
  margin-bottom: var(--space-4);
  text-align: left;
}

label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 6px;
}

input[type="text"],
input[type="tel"],
input[type="number"],
input[type="date"],
input[type="email"],
input[type="password"],
input[type="search"],
select,
textarea {
  width: 100%;
  padding: 11px 14px;
  background: var(--bg-surface-2);
  border: 1px solid var(--line-default);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.9375rem;
  font-family: var(--font-sans);
  transition: border-color var(--dur-fast) var(--ease-out),
              background-color var(--dur-fast) var(--ease-out);
  appearance: none;
  -webkit-appearance: none;
}

input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--red-core);
  background: var(--bg-elevated);
}

input::placeholder { color: var(--text-muted); }

select {
  background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23A6A5A1' stroke-width='2'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 14px;
  padding-right: 36px;
  cursor: pointer;
}

select option { background: var(--bg-surface); color: var(--text-primary); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 12px 20px;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease-out),
              color var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-block { display: flex; width: 100%; }
.btn-sm { padding: 8px 14px; font-size: 0.8125rem; }

.btn-primary {
  background: var(--red-core);
  color: #FFFFFF;
}
.btn-primary:hover { background: var(--red-hover); }
.btn-primary:disabled { opacity: 0.55; cursor: not-allowed; }

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: var(--line-default);
}
.btn-ghost:hover { color: var(--text-primary); border-color: var(--line-strong); }

.btn-ghost-plain {
  background: transparent;
  color: var(--text-secondary);
}
.btn-ghost-plain:hover { color: var(--text-primary); }

.btn-sm-danger {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--line-default);
  padding: 6px 12px;
  font-size: 0.75rem;
  border-radius: var(--radius-md);
}
.btn-sm-danger:hover { color: var(--red-core); border-color: rgba(200,30,30,0.4); }

.form-message {
  margin-top: var(--space-3);
  min-height: 1.2em;
  font-size: 0.8125rem;
  color: var(--text-secondary);
  text-align: center;
}
.form-message.error { color: #E38B8B; }
.form-message.success { color: var(--green-attend); }

/* ============================================================
   APP SHELL
   ============================================================ */

.app-shell {
  display: none;
  grid-template-columns: var(--sidebar-width) 1fr;
  height: 100vh;
  width: 100%;
}
.app-shell.active { display: grid; }

/* ---------- Sidebar ---------- */
.sidebar {
  background: var(--bg-surface);
  border-right: 1px solid var(--line-subtle);
  display: flex;
  flex-direction: column;
  padding: var(--space-5) var(--space-4);
  overflow-y: auto;
}

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 0 var(--space-3) var(--space-5);
  border-bottom: 1px solid var(--line-subtle);
  margin-bottom: var(--space-5);
}

.brand-logo { height: 26px; width: auto; }

.brand-label {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 1;
}

.sidebar-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 10px 12px;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  transition: background-color var(--dur-fast) var(--ease-out),
              color var(--dur-fast) var(--ease-out);
  text-align: left;
  width: 100%;
}

.sidebar-link svg { width: 18px; height: 18px; flex-shrink: 0; }

.sidebar-link:hover {
  background: var(--bg-surface-2);
  color: var(--text-primary);
}

.sidebar-link.active {
  background: var(--bg-surface-2);
  color: var(--text-primary);
}

.sidebar-footer {
  border-top: 1px solid var(--line-subtle);
  padding-top: var(--space-4);
  margin-top: var(--space-4);
}

.admin-chip {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 8px;
  margin-bottom: var(--space-3);
}

.admin-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--bg-surface-2);
  border: 1px solid var(--line-default);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-size: 0.875rem;
  flex-shrink: 0;
}

.admin-meta {
  display: flex;
  flex-direction: column;
  gap: 1px;
  min-width: 0;
}

.admin-name {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.admin-email {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ---------- Main ---------- */
.main {
  overflow-y: auto;
  padding: var(--space-6) var(--space-7);
}

.tab-panel { display: none; }
.tab-panel.active { display: block; }

.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

/* ============================================================
   CARDS & STATS
   ============================================================ */

.card {
  background: var(--bg-surface);
  border: 1px solid var(--line-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  margin-bottom: var(--space-5);
}

.card-header { margin-bottom: var(--space-4); }
.card-sub {
  color: var(--text-secondary);
  font-size: 0.8125rem;
  margin-top: 2px;
}

.stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-4);
  margin-bottom: var(--space-5);
}

.stat-card {
  background: var(--bg-surface);
  border: 1px solid var(--line-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.stat-value {
  font-family: var(--font-display);
  font-size: 2.25rem;
  line-height: 1;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.stat-value.is-due { color: var(--amber); }
.stat-value.is-overdue { color: var(--red-core); }

/* ---------- Attention list ---------- */
.attention-list {
  display: flex;
  flex-direction: column;
}

.attention-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--line-subtle);
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease-out);
  padding-left: var(--space-3);
  padding-right: var(--space-3);
  border-radius: var(--radius-md);
}

.attention-item:hover { background: var(--bg-surface-2); }
.attention-item:last-child { border-bottom: none; }

.attention-name {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-primary);
}

.attention-meta {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  margin-top: 2px;
}

.attention-right {
  text-align: right;
  flex-shrink: 0;
}

.attention-amount {
  font-family: var(--font-display);
  font-size: 1.125rem;
  color: var(--text-primary);
}

.attention-days {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  margin-top: 2px;
  letter-spacing: 0.05em;
}

.empty-state {
  text-align: center;
  padding: var(--space-6) var(--space-4);
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* ============================================================
   TOOLBAR & TABLE
   ============================================================ */

.toolbar {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.toolbar input[type="search"] {
  flex: 1;
  max-width: 360px;
}

.toolbar select { width: 180px; }

.toolbar-count {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.table-card { padding: 0; overflow: hidden; }

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

.data-table thead th {
  text-align: left;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 14px 20px;
  border-bottom: 1px solid var(--line-subtle);
  background: var(--bg-surface-2);
  white-space: nowrap;
}

.data-table tbody td {
  padding: 14px 20px;
  border-bottom: 1px solid var(--line-subtle);
  font-size: 0.875rem;
  color: var(--text-primary);
  vertical-align: middle;
}

.data-table tbody tr:last-child td { border-bottom: none; }

.data-table tbody tr {
  transition: background-color var(--dur-fast) var(--ease-out);
}

.data-table tbody tr.is-clickable { cursor: pointer; }
.data-table tbody tr.is-clickable:hover { background: var(--bg-surface-2); }

.col-amount { text-align: right; }
.col-action { width: 40px; }

.cell-amount {
  font-family: var(--font-display);
  font-size: 1rem;
}

.cell-name { font-weight: 500; }

.cell-sub {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  margin-top: 2px;
  letter-spacing: 0.05em;
}

/* ---------- Status pills ---------- */
.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: 1px solid transparent;
}

.status-pill::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.status-paid {
  color: var(--green-attend);
  background: rgba(79, 169, 104, 0.10);
  border-color: rgba(79, 169, 104, 0.25);
}

.status-due {
  color: var(--amber);
  background: rgba(199, 154, 60, 0.10);
  border-color: rgba(199, 154, 60, 0.25);
}

.status-overdue {
  color: #E38B8B;
  background: var(--red-tint);
  border-color: rgba(200, 30, 30, 0.30);
}

/* ============================================================
   DRAWER
   ============================================================ */

.drawer {
  position: fixed;
  inset: 0;
  z-index: 200;
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--dur-base) var(--ease-out);
}

.drawer.open {
  pointer-events: auto;
  opacity: 1;
}

.drawer-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
}

.drawer-panel {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: 480px;
  max-width: 100%;
  background: var(--bg-surface);
  border-left: 1px solid var(--line-subtle);
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform var(--dur-base) var(--ease-out);
}

.drawer.open .drawer-panel { transform: translateX(0); }

.drawer-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-5);
  border-bottom: 1px solid var(--line-subtle);
}

.drawer-header h2 { margin-bottom: 2px; }

.drawer-sub {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.drawer-close {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  flex-shrink: 0;
}
.drawer-close:hover { color: var(--text-primary); background: var(--bg-surface-2); }
.drawer-close svg { width: 18px; height: 18px; }

.drawer-body {
  flex: 1;
  overflow-y: auto;
  padding: var(--space-5);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.drawer-section {
  background: var(--bg-surface-2);
  border-radius: var(--radius-md);
  padding: var(--space-4);
}

.drawer-section h3 {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: var(--space-3);
}

.detail-list { display: flex; flex-direction: column; }

.detail-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: var(--space-4);
  padding: 8px 0;
  border-bottom: 1px solid var(--line-subtle);
  font-size: 0.875rem;
}
.detail-row:last-child { border-bottom: none; }
.detail-row:first-child { padding-top: 0; }

.detail-row dt {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  color: var(--text-muted);
  flex-shrink: 0;
}

.detail-row dd {
  color: var(--text-primary);
  text-align: right;
  overflow-wrap: break-word;
}

.drawer-actions {
  display: flex;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.drawer-actions .btn { flex: 1; }

.drawer-edit-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
}

.drawer-edit-grid .form-group { margin-bottom: 0; }

.payment-history {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  max-height: 220px;
  overflow-y: auto;
}

.payment-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 8px 0;
  border-bottom: 1px solid var(--line-subtle);
  font-size: 0.8125rem;
}

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

.payment-date {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  letter-spacing: 0.05em;
}

.payment-amount {
  font-family: var(--font-display);
  font-size: 0.9375rem;
  color: var(--text-primary);
}

/* ============================================================
   TOAST
   ============================================================ */

.toast {
  position: fixed;
  bottom: var(--space-5);
  left: 50%;
  transform: translate(-50%, 120%);
  background: var(--bg-elevated);
  border: 1px solid var(--line-default);
  border-radius: var(--radius-md);
  padding: 12px 20px;
  font-size: 0.875rem;
  color: var(--text-primary);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
  transition: transform var(--dur-base) var(--ease-out);
  z-index: 300;
  pointer-events: none;
  max-width: 480px;
}

.toast.show { transform: translate(-50%, 0); }
.toast.error { border-color: rgba(200, 30, 30, 0.4); color: #E38B8B; }
.toast.success { border-color: rgba(79, 169, 104, 0.4); color: var(--green-attend); }

/* ============================================================
   RESPONSIVE — collapse sidebar on small screens
   ============================================================ */

@media (max-width: 900px) {
  :root { --sidebar-width: 200px; }
  .main { padding: var(--space-5); }
}

@media (max-width: 720px) {
  .app-shell { grid-template-columns: 1fr; }
  .sidebar {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    top: auto;
    flex-direction: row;
    padding: var(--space-2) var(--space-3);
    border-right: none;
    border-top: 1px solid var(--line-subtle);
    z-index: 100;
    height: auto;
  }
  .sidebar-brand, .sidebar-footer { display: none; }
  .sidebar-nav {
    flex-direction: row;
    gap: var(--space-2);
    justify-content: space-around;
    width: 100%;
  }
  .sidebar-link {
    flex-direction: column;
    font-size: 0.625rem;
    padding: 6px 8px;
    gap: 4px;
  }
  .main { padding: var(--space-4) var(--space-4) 80px; }
  .stats-row { grid-template-columns: 1fr 1fr; }
  .drawer-panel { width: 100%; }
}