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

:root {
  --green: #22c55e;
  --green-dark: #16a34a;
  --bg: #f3f4f6;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --border: #d1d5db;
  --radius: 8px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
}

.container {
  max-width: 520px;
  margin: 0 auto;
  padding: 20px 16px 40px;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0;
  margin-bottom: 24px;
}

.tab {
  flex: 1;
  padding: 12px;
  text-align: center;
  font-weight: 600;
  font-size: 14px;
  border: 2px solid var(--border);
  background: var(--card);
  color: var(--muted);
  cursor: pointer;
  transition: all .2s;
}

.tab:first-child { border-radius: var(--radius) 0 0 var(--radius); }
.tab:last-child { border-radius: 0 var(--radius) var(--radius) 0; }

.tab.active {
  background: var(--green);
  border-color: var(--green);
  color: #fff;
}

.tab.completed {
  background: var(--green-dark);
  border-color: var(--green-dark);
  color: #fff;
}

/* Steps */
.step { display: none; }
.step.active { display: block; }

/* Card */
.card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: 0 1px 3px rgba(0,0,0,.08);
  margin-bottom: 16px;
}

/* Product */
.product {
  display: flex;
  gap: 16px;
  align-items: center;
  margin-bottom: 20px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}

.product-img {
  width: 80px;
  height: 80px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--green), #059669);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 28px;
  flex-shrink: 0;
}

.product-info h2 {
  font-size: 16px;
  margin-bottom: 4px;
}

.price {
  display: flex;
  align-items: center;
  gap: 8px;
}

.price-old {
  text-decoration: line-through;
  color: var(--muted);
  font-size: 16px;
}

.price-new {
  font-size: 24px;
  font-weight: 700;
  color: var(--green);
}

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

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text);
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: 15px;
  transition: border-color .2s;
  outline: none;
  background: #fff;
}

.form-group input:focus,
.form-group select:focus {
  border-color: var(--green);
}

.form-group input.error {
  border-color: #ef4444;
}

.form-group .error-msg {
  color: #ef4444;
  font-size: 12px;
  margin-top: 4px;
  display: none;
}

.form-group input.error + .error-msg {
  display: block;
}

.phone-row {
  display: flex;
  gap: 8px;
}

.phone-row select {
  width: 110px;
  flex-shrink: 0;
}

.phone-row input {
  flex: 1;
}

.row-2 {
  display: flex;
  gap: 12px;
}

.row-2 .form-group {
  flex: 1;
}

/* Buttons */
.btn {
  width: 100%;
  padding: 14px;
  border: none;
  border-radius: var(--radius);
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: background .2s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

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

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

.btn-primary:disabled {
  background: #9ca3af;
  cursor: not-allowed;
}

.btn-back {
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
  margin-bottom: 12px;
  padding: 10px;
}

/* Spinner */
.spinner {
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255,255,255,.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin .6s linear infinite;
  display: none;
}

@keyframes spin { to { transform: rotate(360deg); } }

.btn.loading .spinner { display: block; }
.btn.loading .btn-text { display: none; }

/* Guarantee */
.guarantee {
  text-align: center;
  padding: 16px;
  color: var(--muted);
  font-size: 13px;
}

.guarantee .shield {
  font-size: 24px;
  display: block;
  margin-bottom: 4px;
}

/* Payment logos */
.pay-logos {
  display: flex;
  justify-content: center;
  gap: 12px;
  padding: 12px 0;
  flex-wrap: wrap;
}

.pay-logo {
  background: #f9fafb;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 6px 10px;
  font-size: 11px;
  font-weight: 700;
  color: var(--muted);
}

/* Payment methods */
.pay-methods {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}

.pay-method {
  flex: 1;
  padding: 10px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  text-align: center;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: all .2s;
  background: #fff;
}

.pay-method.active {
  border-color: var(--green);
  background: #f0fdf4;
}

/* Order summary */
.order-summary {
  background: #f9fafb;
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 20px;
}

.order-line {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  font-size: 14px;
}

.order-line.total {
  border-top: 1px solid var(--border);
  margin-top: 8px;
  padding-top: 12px;
  font-weight: 700;
  font-size: 18px;
}

.order-line.total .amount {
  color: var(--green);
}

/* Toast */
.toast {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%) translateY(-100px);
  background: #ef4444;
  color: #fff;
  padding: 12px 24px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  z-index: 1000;
  transition: transform .3s ease;
  max-width: 90%;
  text-align: center;
}

.toast.show {
  transform: translateX(-50%) translateY(0);
}

.toast.success {
  background: var(--green);
}

/* Success */
.success-view {
  text-align: center;
  padding: 40px 20px;
}

.success-view .checkmark {
  width: 64px;
  height: 64px;
  background: var(--green);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-size: 32px;
  color: #fff;
}

.success-view h2 {
  margin-bottom: 8px;
}

.success-view p {
  color: var(--muted);
}

@media (max-width: 480px) {
  .container { padding: 12px 12px 32px; }
  .card { padding: 18px; }
  .product { flex-direction: column; text-align: center; }
  .price { justify-content: center; }
}