/* ==========================================================================
   School Fee Payment Portal — mobile-first, responsive fintech layout
   ========================================================================== */

:root {
  --color-bg: #f0f4f9;
  --color-surface: #ffffff;
  --color-text: #1a2332;
  --color-text-muted: #5c6b7a;
  --color-border: #e2e8f0;
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-primary-soft: #eff6ff;
  --color-success: #059669;
  --color-success-bg: #ecfdf5;
  --color-danger: #dc2626;
  --color-danger-bg: #fef2f2;
  --color-warning: #d97706;
  --color-warning-bg: #fffbeb;
  --color-orange: #ea580c;
  --color-orange-bg: #fff7ed;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 1px 3px rgba(15, 23, 42, 0.06), 0 4px 14px rgba(15, 23, 42, 0.05);
  --shadow-elevated: 0 8px 30px rgba(15, 23, 42, 0.08);
  --font: "DM Sans", system-ui, -apple-system, sans-serif;
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --touch-min: 48px;
  --transition: 0.2s ease;
  --app-max: 1120px;
  --aside-width: 380px;
}

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

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.5;
  color: var(--color-text);
  background: var(--color-bg);
  min-height: 100dvh;
}

.app {
  width: 100%;
  max-width: var(--app-max);
  margin: 0 auto;
  padding: var(--space-md);
  padding-bottom: var(--space-xl);
}

/* Header */
.header {
  text-align: center;
  padding: var(--space-lg) 0 var(--space-md);
}

.header__title {
  margin: 0;
  font-size: 1.375rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.header__subtitle {
  margin: var(--space-xs) 0 0;
  font-size: 0.9375rem;
  color: var(--color-text-muted);
}

/* Workspace layout */
.main {
  margin: 0;
}

.workspace {
  display: grid;
  gap: var(--space-md);
  align-items: start;
}

.workspace__primary {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  min-width: 0;
}

.workspace__aside {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  min-width: 0;
}

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

/* Tablet: slightly wider, still stacked until desktop */
@media (min-width: 640px) {
  .app {
    padding: var(--space-lg);
  }

  .header__title {
    font-size: 1.5rem;
  }

  .panel--selection .field {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-sm);
    margin-bottom: 0;
  }

  .panel--selection .field--student {
    grid-column: 1 / -1;
    margin-top: var(--space-sm);
  }
}

/* Desktop: two-column dashboard */
@media (min-width: 960px) {
  .workspace--pay-active {
    grid-template-columns: minmax(0, 1fr) var(--aside-width);
    gap: var(--space-xl);
  }

  .workspace__aside {
    position: sticky;
    top: var(--space-md);
  }

  .header {
    text-align: left;
    padding-bottom: var(--space-lg);
  }
}

/* Panels */
.panel,
.card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.panel {
  padding: var(--space-lg);
  opacity: 1;
  transform: translateY(0);
  transition: opacity var(--transition), transform var(--transition), box-shadow var(--transition);
}

.panel.is-entering {
  opacity: 0;
  transform: translateY(8px);
}

.panel__title {
  margin: 0 0 var(--space-md);
  font-size: 1.0625rem;
  font-weight: 600;
}

.panel__meta {
  margin: -0.5rem 0 var(--space-md);
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.panel__hint {
  margin: -0.25rem 0 var(--space-md);
  font-size: 0.9375rem;
  line-height: 1.5;
  color: var(--color-text-muted);
}

.panel__hint strong {
  color: var(--color-text);
  font-weight: 600;
}

.quarter-selection-status {
  margin: 0 0 var(--space-md);
  padding: var(--space-sm) var(--space-md);
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-primary);
  background: var(--color-primary-soft);
  border-radius: var(--radius-sm);
  border: 1px solid #bfdbfe;
}

.card {
  padding: var(--space-lg);
  transition: opacity var(--transition), transform var(--transition);
}

.card.is-entering {
  opacity: 0;
  transform: translateY(8px);
}

.card__heading {
  margin: 0 0 var(--space-md);
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
}

/* Form fields */
.field {
  margin-bottom: var(--space-md);
}

.panel--selection .field {
  margin-bottom: var(--space-xs);
}

.field:last-child {
  margin-bottom: 0;
}

.field__label {
  display: block;
  margin-bottom: var(--space-xs);
  font-size: 0.875rem;
  font-weight: 600;
}

.field__control {
  width: 100%;
  min-height: var(--touch-min);
  padding: 0 var(--space-md);
  font-family: inherit;
  font-size: 1rem;
  color: var(--color-text);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  appearance: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.field__control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.field__control:disabled {
  background: #f1f5f9;
  color: var(--color-text-muted);
  cursor: not-allowed;
}

select.field__control {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%235c6b7a' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  padding-right: 2.5rem;
}

.field__hint {
  margin: var(--space-xs) 0 0;
  font-size: 0.875rem;
  color: var(--color-primary);
}

.field__hint--muted {
  color: var(--color-text-muted);
}

/* Combobox */
.combobox {
  position: relative;
}

.combobox__list {
  position: absolute;
  z-index: 20;
  top: calc(100% + 4px);
  left: 0;
  right: 0;
  max-height: 220px;
  margin: 0;
  padding: var(--space-xs);
  list-style: none;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-elevated);
  overflow-y: auto;
}

.combobox__option {
  padding: var(--space-sm) var(--space-md);
  min-height: var(--touch-min);
  display: flex;
  align-items: center;
  font-size: 1rem;
  border-radius: 6px;
  cursor: pointer;
}

.combobox__option:hover,
.combobox__option.is-focused {
  background: var(--color-primary-soft);
}

.combobox__option[aria-selected="true"] {
  background: var(--color-primary-soft);
  font-weight: 600;
}

/* Student details */
.detail-list {
  margin: 0;
}

.detail-list__row {
  margin-bottom: var(--space-md);
}

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

.detail-list dt {
  margin: 0;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-muted);
}

.detail-list dd {
  margin: 0.125rem 0 0;
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.35;
}

/* Alert */
.alert {
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  margin-bottom: var(--space-md);
}

.alert--warning {
  background: var(--color-warning-bg);
  color: #92400e;
  border: 1px solid #fcd34d;
}

/* Quarter grid */
.quarter-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-sm);
}

@media (min-width: 480px) {
  .quarter-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.quarter-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 88px;
  padding: var(--space-md);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition), transform 0.15s ease;
  -webkit-tap-highlight-color: transparent;
}

.quarter-card__label {
  font-size: 1.125rem;
}

.quarter-card__status {
  margin-top: var(--space-xs);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.quarter-card--paid {
  background: var(--color-success-bg);
  border-color: var(--color-success);
  color: var(--color-success);
  cursor: default;
  opacity: 0.9;
}

.quarter-card--overdue {
  background: var(--color-danger-bg);
  border-color: var(--color-danger);
  color: var(--color-danger);
}

.quarter-card--pending {
  background: var(--color-orange-bg);
  border-color: var(--color-orange);
  color: var(--color-orange);
}

.quarter-card--selected {
  border-color: var(--color-primary);
  background: var(--color-primary-soft);
  color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.quarter-card--selected .quarter-card__label::after {
  content: " ✓";
  font-size: 0.875rem;
}

.quarter-card:not(.quarter-card--paid):active {
  transform: scale(0.98);
}

.quarter-card:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Fee breakdown (aside) */
.breakdown {
  margin: 0;
}

.breakdown__row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--color-border);
}

.breakdown__row:last-child {
  border-bottom: none;
}

.breakdown__row dt {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
}

.breakdown__row dd {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 600;
}

.breakdown__row--total {
  padding-top: var(--space-md);
  margin-top: var(--space-xs);
  border-top: 2px solid var(--color-border);
}

.breakdown__row--total dt,
.breakdown__row--total dd {
  font-size: 1.125rem;
  font-weight: 700;
}

.breakdown__note {
  margin: 0 0 var(--space-sm);
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  line-height: 1.45;
}

/* Payment panel — focus state */
.panel--payment.panel--payment-ready {
  border: 1px solid #bfdbfe;
  box-shadow: var(--shadow-elevated);
}

.panel--payment .panel__title {
  color: var(--color-primary);
}

/* Pay hero — amount & quarters above QR */
.pay-hero {
  text-align: center;
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border);
}

.pay-hero__label {
  margin: 0;
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
}

.pay-hero__amount {
  margin: var(--space-xs) 0 var(--space-sm);
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-text);
  line-height: 1.2;
}

@media (min-width: 960px) {
  .pay-hero__amount {
    font-size: 2.25rem;
  }
}

.pay-chips {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-xs);
}

.pay-chip {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-primary);
  background: var(--color-primary-soft);
  border-radius: 999px;
}

/* QR stage */
.qr-stage {
  margin-bottom: var(--space-lg);
}

.qr-stage__empty {
  margin: 0;
  padding: var(--space-xl) var(--space-md);
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  text-align: center;
  background: #f8fafc;
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
}

.qr-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-lg);
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: 0 4px 24px rgba(15, 23, 42, 0.06);
}

.qr-stage--ready .qr-panel {
  animation: qrFadeIn 0.25s ease;
}

@keyframes qrFadeIn {
  from {
    opacity: 0;
    transform: scale(0.98);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.qr-container {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 220px;
  max-width: 100%;
  margin: 0 auto;
  padding: var(--space-md);
  background: #ffffff;
  border-radius: var(--radius-sm);
  line-height: 0;
  overflow: hidden;
}

.qr-logo {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 52px;
  height: 52px;
  transform: translate(-50%, -50%);
  z-index: 5;

  background: white;
  border-radius: 50%;
  padding: 6px;

  object-fit: contain;

  box-shadow:
    0 2px 10px rgba(0,0,0,0.12),
    0 0 0 4px white;
}

@media (min-width: 960px) {
  .qr-container {
    width: 260px;
  }
}

.qr-container table {
  margin: 0 auto !important;
  border: 0 !important;
  border-collapse: collapse;
}

/* Image (preferred — works on all mobile browsers) */
.qr-container > img.qr-image {
  display: block !important;
  width: 220px;
  max-width: 100%;
  height: auto;
  aspect-ratio: 1;
  object-fit: contain;
  border-radius: 4px;
}

/* Fallback if canvas is kept (older WebKit) */
.qr-container canvas {
  display: block !important;
  width: 220px;
  max-width: 100%;
  height: auto;
  aspect-ratio: 1;
}

@media (min-width: 960px) {
 .qr-container > img.qr-image
  .qr-container canvas {
    width: 260px;
  }
}

/* After "I Have Paid" — hide QR and UPI pay button */
.payment--submitted .qr-stage,
.payment--submitted #upiPayBtn {
  display: none !important;
}

.qr-panel:not([hidden]) {
  display: flex;
}

.qr-image {
  display: block;
  width: 100%;
  max-width: 220px;
  height: auto;
  aspect-ratio: 1;
  object-fit: contain;
  margin: 0 auto;
}

@media (min-width: 960px) {
  .qr-image {
    max-width: 260px;
  }
}

.qr-panel__hint {
  margin: var(--space-md) 0 0;
  font-size: 0.875rem;
  color: var(--color-text-muted);
  text-align: center;
  line-height: 1.45;
}

/* Collapsible payment details */
.payment-details {
  margin-bottom: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: #f8fafc;
}

.payment-details__summary {
  padding: var(--space-sm) var(--space-md);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-muted);
  cursor: pointer;
  list-style: none;
}

.payment-details__summary::-webkit-details-marker {
  display: none;
}

.payment-details[open] .payment-details__summary {
  border-bottom: 1px solid var(--color-border);
}

.payment-summary {
  padding: var(--space-sm) var(--space-md) var(--space-md);
}

.payment-summary__row {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-xs) 0;
  font-size: 0.875rem;
}

.payment-summary__label {
  color: var(--color-text-muted);
}

.payment-summary__value {
  font-weight: 600;
  text-align: right;
  word-break: break-word;
}

.payment-summary__value--mono {
  font-family: ui-monospace, "Cascadia Mono", monospace;
  font-size: 0.75rem;
  font-weight: 500;
}

.payment-actions {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.btn {
  display: block;
  width: 100%;
  min-height: var(--touch-min);
  padding: 0 var(--space-lg);
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition), opacity var(--transition);
  -webkit-tap-highlight-color: transparent;
}

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

.btn--primary:hover:not(:disabled) {
  background: var(--color-primary-hover);
}

.btn--secondary {
  color: var(--color-primary);
  background: var(--color-surface);
  border: 2px solid var(--color-primary);
}

.btn--secondary:hover:not(:disabled) {
  background: var(--color-primary-soft);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.processing {
  margin-top: var(--space-md);
  padding: var(--space-lg);
  text-align: center;
  background: var(--color-success-bg);
  border-radius: var(--radius-sm);
  border: 1px solid #a7f3d0;
}

.processing__text {
  margin: 0;
  font-size: 1rem;
  line-height: 1.6;
  color: #065f46;
}

.footer {
  text-align: center;
  padding: var(--space-md) 0;
}

.footer p {
  margin: 0;
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}