/* ================================================================
   PayQR — Style System
   ================================================================ */

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

:root {
  --bg-deep: #060608;
  --bg-base: #0c0c10;
  --bg-surface: #141418;
  --bg-elevated: #1a1a20;
  --bg-hover: #222228;

  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-default: rgba(255, 255, 255, 0.10);
  --border-focus: #00c896;

  --text-primary: #eaeaef;
  --text-secondary: #8e8e9a;
  --text-muted: #5a5a66;
  --text-inverse: #0c0c10;

  --accent: #00c896;
  --accent-dim: rgba(0, 200, 150, 0.12);
  --accent-glow: rgba(0, 200, 150, 0.25);
  --accent-hover: #00dda6;

  --danger: #ff4d6a;
  --warning: #f5a623;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --shadow-card: 0 1px 3px rgba(0, 0, 0, .4), 0 8px 32px rgba(0, 0, 0, .35);
  --shadow-glow: 0 0 40px rgba(0, 200, 150, 0.08);

  --transition-fast: 150ms cubic-bezier(.4, 0, .2, 1);
  --transition-base: 250ms cubic-bezier(.4, 0, .2, 1);
  --transition-slow: 400ms cubic-bezier(.4, 0, .2, 1);
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-deep);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* --- Ambient Background Glows --- */
.ambient-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(120px);
  pointer-events: none;
  z-index: 0;
  opacity: 0.35;
}

.ambient-glow--1 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(0, 200, 150, 0.15), transparent 70%);
  top: -100px;
  right: -100px;
  animation: floatGlow1 20s ease-in-out infinite;
}

.ambient-glow--2 {
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(0, 150, 200, 0.10), transparent 70%);
  bottom: -50px;
  left: -80px;
  animation: floatGlow2 25s ease-in-out infinite;
}

@keyframes floatGlow1 {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  33% {
    transform: translate(-40px, 30px) scale(1.1);
  }

  66% {
    transform: translate(20px, -20px) scale(0.95);
  }
}

@keyframes floatGlow2 {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  50% {
    transform: translate(30px, -40px) scale(1.08);
  }
}

/* --- Header --- */
.site-header {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 48px 20px 12px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}

.logo-icon {
  width: 30px;
  height: 30px;
  color: var(--accent);
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  color: var(--text-primary);
}

.logo-accent {
  color: var(--accent);
}

.header-tagline {
  font-size: 0.875rem;
  color: var(--text-muted);
  font-weight: 400;
  letter-spacing: 0.2px;
}

/* --- Main Container --- */
.main-container {
  position: relative;
  z-index: 2;
  max-width: 480px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}

/* --- Tab Bar --- */
.tab-bar {
  display: flex;
  position: relative;
  background: var(--bg-surface);
  border-radius: var(--radius-md);
  padding: 4px;
  margin-bottom: 28px;
  border: 1px solid var(--border-subtle);
}

.tab-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 16px;
  background: transparent;
  border: none;
  border-radius: calc(var(--radius-md) - 3px);
  color: var(--text-muted);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: color var(--transition-base);
  position: relative;
  z-index: 1;
}

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

.tab-btn.active {
  color: var(--text-primary);
}

.tab-indicator {
  position: absolute;
  top: 4px;
  left: 4px;
  width: calc(50% - 4px);
  height: calc(100% - 8px);
  background: var(--bg-elevated);
  border-radius: calc(var(--radius-md) - 3px);
  transition: transform var(--transition-base);
  box-shadow: 0 1px 4px rgba(0, 0, 0, .3);
}

.tab-bar[data-active="upi"] .tab-indicator {
  transform: translateX(calc(100% + 4px));
}

/* --- Tab Panels --- */
.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
  animation: panelIn 0.35s ease-out;
}

@keyframes panelIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* --- Card --- */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.card-body {
  padding: 28px 24px 24px;
}

/* --- Section Title --- */
.section-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--text-muted);
  margin-bottom: 20px;
}

/* --- Fields --- */
.field {
  margin-bottom: 20px;
}

.field-label {
  display: block;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.field-label-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 6px;
}

.field-label-row .field-label {
  margin-bottom: 0;
}

.field-input {
  width: 100%;
  padding: 11px 14px;
  background: var(--bg-base);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  outline: none;
}

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

.field-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-dim);
}

.field-input:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.field-input.has-error {
  border-color: var(--danger);
  box-shadow: 0 0 0 3px rgba(255, 77, 106, 0.12);
}

.field-textarea {
  resize: vertical;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.5;
}

.field-hint {
  display: block;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 5px;
}

.field-error {
  display: block;
  font-size: 0.75rem;
  color: var(--danger);
  margin-top: 5px;
  min-height: 0;
}

.field-row {
  display: flex;
  gap: 12px;
}

.field--grow {
  flex: 1;
}

.optional-tag {
  font-size: 0.6875rem;
  font-weight: 400;
  color: var(--text-muted);
  font-style: italic;
}

/* --- Toggle Switch --- */
.toggle-switch {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
}

.toggle-switch input {
  display: none;
}

.toggle-track {
  position: relative;
  width: 36px;
  height: 20px;
  background: var(--bg-hover);
  border-radius: 12px;
  border: 1px solid var(--border-default);
  transition: background var(--transition-fast), border-color var(--transition-fast);
}

.toggle-track::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 14px;
  height: 14px;
  background: var(--text-muted);
  border-radius: 50%;
  transition: transform var(--transition-fast), background var(--transition-fast);
}

.toggle-switch input:checked+.toggle-track {
  background: var(--accent-dim);
  border-color: var(--accent);
}

.toggle-switch input:checked+.toggle-track::after {
  transform: translateX(16px);
  background: var(--accent);
}

.toggle-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.toggle-switch input:checked~.toggle-label {
  color: var(--accent);
}

/* --- Buttons --- */
.btn-primary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  padding: 13px 20px;
  background: var(--accent);
  color: var(--text-inverse);
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
  margin-top: 4px;
  position: relative;
  overflow: hidden;
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 4px 20px var(--accent-glow);
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: translateY(0) scale(0.985);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 16px;
  background: var(--bg-elevated);
  color: var(--text-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
}

.btn-secondary:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  border-color: rgba(255, 255, 255, .15);
}

/* --- QR Output --- */
.qr-output {
  margin-top: 28px;
}

.qr-output.hidden {
  display: none;
}

.qr-output.visible {
  animation: qrReveal 0.5s ease-out;
}

@keyframes qrReveal {
  from {
    opacity: 0;
    transform: scale(0.92) translateY(16px);
  }

  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

.qr-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card), var(--shadow-glow);
  padding: 28px 24px;
  text-align: center;
  position: relative;
}

.qr-badge {
  display: inline-block;
  padding: 3px 12px;
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  border-radius: 20px;
  background: var(--accent-dim);
  color: var(--accent);
  margin-bottom: 20px;
}

.qr-badge.expired {
  background: rgba(255, 77, 106, 0.12);
  color: var(--danger);
}

.qr-frame {
  display: inline-block;
  background: #ffffff;
  border-radius: var(--radius-md);
  padding: 16px;
  margin-bottom: 20px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, .2);
}

.qr-meta {
  margin-bottom: 20px;
}

.qr-payee {
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 2px;
}

.qr-upi {
  font-size: 0.8125rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 4px;
}

.qr-amount {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--accent);
}

.qr-expiry {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.qr-actions {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

.upi-link-display {
  margin-top: 16px;
  padding: 10px 14px;
  background: var(--bg-base);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  word-break: break-all;
  line-height: 1.5;
  text-align: left;
}

/* --- Footer --- */
.site-footer {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 20px;
  border-top: 1px solid var(--border-subtle);
}

.site-footer p {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* --- Toast --- */
.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--bg-elevated);
  color: var(--text-primary);
  padding: 10px 20px;
  border-radius: var(--radius-xl);
  font-size: 0.8125rem;
  font-weight: 500;
  box-shadow: 0 4px 24px rgba(0, 0, 0, .5);
  border: 1px solid var(--border-default);
  z-index: 999;
  opacity: 0;
  transition: opacity var(--transition-base), transform var(--transition-base);
  pointer-events: none;
}

.toast.visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.toast.hidden {
  display: block;
  opacity: 0;
  transform: translateX(-50%) translateY(20px);
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--bg-hover);
  border-radius: 8px;
}

/* --- Date input fix for dark mode --- */
input[type="date"]::-webkit-calendar-picker-indicator {
  filter: invert(0.7);
  cursor: pointer;
}

/* --- Number input arrows --- */
input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
  opacity: 0.5;
}

/* --- Responsive --- */
@media (max-width: 520px) {
  .main-container {
    padding: 16px 14px 48px;
  }

  .card-body {
    padding: 22px 18px 20px;
  }

  .qr-card {
    padding: 22px 18px;
  }

  .qr-actions {
    flex-direction: column;
  }

  .btn-secondary {
    justify-content: center;
  }

  .site-header {
    padding-top: 32px;
  }
}