/* ============================================================
   BMI Contact Manager — Design System
   Swiss grid, minimal, mobile-first
   ============================================================ */

/* --- CSS Custom Properties --- */
:root {
  --bg: #FFFFFF;
  --surface: #F8F8F8;
  --text-primary: #1A1A1A;
  --text-secondary: #6B7280;
  --accent: #2563EB;
  --accent-hover: #1D4ED8;
  --accent-active: #1E40AF;
  --accent-disabled: #93C5FD;
  --error: #DC2626;
  --error-bg: #FEF2F2;
  --success: #16A34A;
  --warning: #D97706;
  --border: #E5E7EB;
  --row-hover: #F3F4F6;

  --font: "Helvetica Neue", -apple-system, Arial, sans-serif;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;

  --radius: 4px;
  --radius-lg: 8px;

  --transition: 150ms ease-out;
  --transition-modal: 150ms ease-in-out;
}

/* --- Reset & Base --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  font-size: 14px;
  font-weight: 400;
  line-height: 1.4;
  color: var(--text-primary);
  background: var(--bg);
  min-height: 100vh;
}

button {
  font-family: var(--font);
  cursor: pointer;
  border: none;
  background: none;
}

input {
  font-family: var(--font);
}

/* --- Layout --- */
.app {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 var(--space-4);
}

/* --- Header --- */
.header {
  padding: var(--space-4) 0 var(--space-3);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.page-title {
  font-size: 20px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--text-primary);
}

.search-wrap {
  margin-top: var(--space-2);
}

/* --- Search Input --- */
.search-input {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  font-size: 14px;
  font-weight: 400;
  color: var(--text-primary);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  outline: none;
  transition: box-shadow var(--transition);
  -webkit-appearance: none;
}

.search-input::placeholder {
  color: var(--text-secondary);
}

.search-input:focus {
  box-shadow: 0 0 0 2px var(--accent);
}

/* --- Main --- */
.main {
  padding-bottom: var(--space-8);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-4);
  font-size: 14px;
  font-weight: 500;
  line-height: 1;
  border-radius: var(--radius);
  transition: background-color var(--transition), color var(--transition);
  white-space: nowrap;
}

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

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

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

.btn-primary:disabled {
  background: var(--accent-disabled);
  color: #fff;
  cursor: not-allowed;
}

.btn-ghost {
  background: transparent;
  color: var(--accent);
  padding: var(--space-2) var(--space-4);
}

.btn-ghost:hover {
  background: rgba(37, 99, 235, 0.08);
}

.btn-ghost:active {
  background: rgba(37, 99, 235, 0.15);
}

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

.btn-danger:hover {
  background: #B91C1C;
}

/* --- Icon Buttons --- */
.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  padding: var(--space-2);
  border-radius: var(--radius);
  color: var(--text-secondary);
  transition: background-color var(--transition), color var(--transition);
  flex-shrink: 0;
}

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

.btn-icon.btn-edit:hover {
  color: var(--accent);
}

.btn-icon.btn-delete:hover {
  color: var(--error);
}

.btn-icon svg {
  display: block;
  flex-shrink: 0;
}

/* --- Contact Table (Desktop) --- */
.contacts-table {
  width: 100%;
  border-collapse: collapse;
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.contacts-table thead tr {
  background: var(--surface);
  border-bottom: 2px solid var(--border);
}

.contacts-table th {
  padding: var(--space-2) var(--space-3);
  font-size: 12px;
  font-weight: 600;
  text-align: left;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-secondary);
  white-space: nowrap;
}

.contacts-table th.col-actions {
  text-align: right;
}

.contacts-table td {
  padding: var(--space-3);
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.contacts-table tbody tr {
  transition: background-color var(--transition);
}

.contacts-table tbody tr:hover {
  background: var(--row-hover);
}

.contacts-table .col-actions {
  text-align: right;
  white-space: nowrap;
}

.contacts-table .contact-name {
  font-weight: 500;
}

.contacts-table .contact-email {
  color: var(--text-secondary);
}

.contacts-table .contact-phone {
  color: var(--text-secondary);
}

/* --- Inline Add/Edit Row (Desktop) --- */
.inline-form-row td {
  padding: var(--space-3);
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.inline-form {
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.inline-form .form-group {
  flex: 1;
  min-width: 120px;
}

.inline-form input {
  width: 100%;
  padding: var(--space-2);
  font-size: 14px;
  color: var(--text-primary);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  outline: none;
  transition: box-shadow var(--transition);
}

.inline-form input:focus {
  box-shadow: 0 0 0 2px var(--accent);
}

.inline-form input.error {
  border-color: var(--error);
}

.inline-form .form-error {
  display: block;
  font-size: 12px;
  color: var(--error);
  margin-top: var(--space-1);
}

.inline-form .btn {
  margin-top: 1px;
}

/* --- Contact Cards (Mobile) --- */
.contact-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: var(--space-3);
  margin-bottom: var(--space-2);
}

.contact-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-2);
  margin-bottom: var(--space-2);
}

.contact-card-name {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
}

.contact-card-actions {
  display: flex;
  gap: var(--space-1);
  flex-shrink: 0;
}

.contact-card-detail {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: var(--space-1);
}

.contact-card-detail:last-child {
  margin-bottom: 0;
}

/* --- Empty State --- */
.empty-state {
  text-align: center;
  padding: var(--space-10) var(--space-4);
  color: var(--text-secondary);
}

.empty-state p {
  font-size: 14px;
}

.empty-state .empty-state-sub {
  font-size: 12px;
  margin-top: var(--space-2);
}

/* --- Form Elements (shared) --- */
.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.form-group label {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-primary);
}

.label-optional {
  font-weight: 400;
  color: var(--text-secondary);
}

.form-error {
  font-size: 12px;
  color: var(--error);
  min-height: 16px;
}

.form-error.visible {
  display: block;
}

/* --- Inline Form Validation Error Container --- */
.inline-form .form-group {
  position: relative;
}

.inline-form .form-error {
  position: absolute;
  bottom: -18px;
  left: 0;
}

/* --- Export Button --- */
.export-wrap {
  margin-top: var(--space-4);
}

.btn-export {
  border: 1px solid transparent;
}

.btn-export:hover {
  border-color: var(--accent);
}

/* --- Toast --- */
.toast-region {
  position: fixed;
  bottom: var(--space-6);
  left: 50%;
  transform: translateX(-50%);
  z-index: 1000;
  pointer-events: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.toast {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  padding: var(--space-3) var(--space-4);
  font-size: 13px;
  font-weight: 500;
  line-height: 1.2;
  color: var(--text-primary);
  pointer-events: auto;
  animation: toast-in var(--transition) ease-out forwards;
  min-width: 200px;
  max-width: 360px;
  text-align: center;
  border-left-width: 3px;
}

.toast.toast-out {
  animation: toast-out var(--transition) ease-in forwards;
}

.toast.toast-success {
  border-left-color: var(--success);
}

.toast.toast-error {
  border-left-color: var(--error);
}

.toast.toast-warning {
  border-left-color: var(--warning);
}

@keyframes toast-in {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes toast-out {
  from { opacity: 1; transform: translateY(0); }
  to   { opacity: 0; transform: translateY(8px); }
}

/* --- Modal Overlay --- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 900;
  padding: var(--space-4);
  animation: modal-overlay-in var(--transition-modal) ease-out;
}

.modal-overlay[hidden] {
  display: none;
}

.modal-overlay.modal-closing {
  animation: modal-overlay-out var(--transition-modal) ease-in forwards;
}

@keyframes modal-overlay-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes modal-overlay-out {
  from { opacity: 1; }
  to   { opacity: 0; }
}

.modal-panel {
  background: var(--bg);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 400px;
  animation: modal-panel-in var(--transition-modal) ease-out;
}

.modal-panel--sm {
  max-width: 360px;
}

@keyframes modal-panel-in {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4);
  border-bottom: 1px solid var(--border);
}

.modal-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.modal-form {
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.modal-body-text {
  padding: var(--space-4);
  font-size: 14px;
  color: var(--text-secondary);
}

.modal-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-2);
  padding: var(--space-4);
  border-top: 1px solid var(--border);
}

.modal-form .modal-actions {
  border-top: none;
  padding: 0;
}

/* --- Responsive: Desktop Table (≥640px) --- */
@media (min-width: 640px) {
  .app {
    padding: 0 var(--space-6);
  }

  .contacts-list {
    display: none;
  }

  .contacts-table-wrap {
    display: block;
  }
}

/* --- Responsive: Mobile Cards (<640px) --- */
@media (max-width: 639px) {
  .contacts-table-wrap {
    display: none;
  }

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

/* --- Reduced Motion --- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}