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

:root {
  --primary-color: #4361ee;
  --primary-dark: #3a56d4;
  --secondary-color: #7209b7;
  --success-color: #06d6a0;
  --danger-color: #ef476f;
  --warning-color: #ffd166;
  --dark-color: #1e1e2f;
  --light-color: #f8f9fa;
  --gray-color: #6c757d;
  --border-radius: 12px;
  --box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  --box-shadow-hover: 0 15px 40px rgba(67, 97, 238, 0.15);
  --transition: all 0.3s ease;
}

body {
  font-family:
    "Inter",
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  color: var(--dark-color);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

/* Header */
header {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius);
  padding: 20px 30px;
  margin-bottom: 30px;
  box-shadow: var(--box-shadow);
  display: flex;
  justify-content: space-between;
  align-items: center;
  border: 1px solid rgba(255, 255, 255, 0.2);
  animation: slideDown 0.5s ease;
}

@keyframes slideDown {
  from {
    transform: translateY(-20px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

h1 {
  font-size: 28px;
  font-weight: 700;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Навигация */
.main-nav {
  display: flex;
  gap: 15px;
  align-items: center;
}

.nav-link {
  text-decoration: none;
  color: var(--gray-color);
  padding: 10px 20px;
  border-radius: 30px;
  font-weight: 500;
  transition: var(--transition);
  position: relative;
}

.nav-link:hover {
  color: var(--primary-color);
  background: rgba(67, 97, 238, 0.05);
}

.nav-link.active {
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  color: white;
  box-shadow: 0 5px 15px rgba(67, 97, 238, 0.3);
}

/* Кнопки */
.btn {
  padding: 12px 24px;
  border: none;
  border-radius: 30px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  transition: var(--transition);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition:
    width 0.6s,
    height 0.6s;
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  color: white;
  box-shadow: 0 5px 15px rgba(67, 97, 238, 0.3);
}

.btn-primary:hover {
  box-shadow: 0 8px 25px rgba(67, 97, 238, 0.4);
}

.btn-success {
  background: linear-gradient(135deg, #06d6a0, #1b9aaa);
  color: white;
  box-shadow: 0 5px 15px rgba(6, 214, 160, 0.3);
}

.btn-danger {
  background: linear-gradient(135deg, #ef476f, #d62828);
  color: white;
  box-shadow: 0 5px 15px rgba(239, 71, 111, 0.3);
}

/* Каталог */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 25px;
  animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.product-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  padding: 20px;
  box-shadow: var(--box-shadow);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.product-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  transform: translateX(-100%);
  transition: transform 0.3s ease;
}

.product-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--box-shadow-hover);
}

.product-card:hover::before {
  transform: translateX(0);
}

.product-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--dark-color);
}

.product-card .price {
  font-size: 24px;
  font-weight: 700;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin: 15px 0 10px;
}

.product-card .stock {
  color: var(--gray-color);
  font-size: 14px;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 5px;
}

.product-card button {
  margin-top: auto;
  width: 100%;
}

/* Корзина */
.cart-items {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 30px;
}

.cart-item {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius);
  padding: 25px;
  box-shadow: var(--box-shadow);
  display: flex;
  justify-content: space-between;
  align-items: center;
  animation: slideIn 0.3s ease;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

@keyframes slideIn {
  from {
    transform: translateX(-20px);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.cart-item-info h3 {
  font-size: 18px;
  margin-bottom: 5px;
  color: var(--dark-color);
}

.cart-item-info p {
  color: var(--gray-color);
  font-size: 14px;
}

.cart-item-actions {
  display: flex;
  align-items: center;
  gap: 15px;
}

.cart-item-actions input {
  width: 80px;
  padding: 10px;
  border: 2px solid #e0e0e0;
  border-radius: 30px;
  text-align: center;
  font-size: 16px;
  transition: var(--transition);
}

.cart-item-actions input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.1);
}

.cart-item-actions button {
  padding: 10px 20px;
  font-size: 13px;
}

/* Баланс */
.balance-info {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  padding: 20px 25px;
  border-radius: var(--border-radius);
  margin-bottom: 25px;
  box-shadow: var(--box-shadow);
  font-size: 18px;
  display: flex;
  align-items: center;
  gap: 15px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% {
    box-shadow: 0 5px 20px rgba(67, 97, 238, 0.2);
  }
  50% {
    box-shadow: 0 5px 30px rgba(67, 97, 238, 0.4);
  }
  100% {
    box-shadow: 0 5px 20px rgba(67, 97, 238, 0.2);
  }
}

#balance {
  font-size: 32px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--success-color), #1b9aaa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Кнопка покупки */
.buy-btn {
  width: 100%;
  padding: 18px;
  font-size: 18px;
  margin-top: 20px;
  background: linear-gradient(135deg, var(--success-color), #1b9aaa);
  box-shadow: 0 10px 30px rgba(6, 214, 160, 0.3);
}

.buy-btn:hover {
  box-shadow: 0 15px 40px rgba(6, 214, 160, 0.4);
}

/* Логин */
.login-container {
  max-width: 450px;
  margin: 100px auto;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  padding: 40px;
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  animation: scaleIn 0.5s ease;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

@keyframes scaleIn {
  from {
    transform: scale(0.9);
    opacity: 0;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}

.login-container h1 {
  text-align: center;
  margin-bottom: 16px;
  font-size: 28px;
}

.login-info {
  text-align: center;
  color: var(--gray-color);
  margin-bottom: 30px;
  font-size: 14px;
  line-height: 1.5;
}

/* Формы */
.form-group {
  margin-bottom: 25px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--dark-color);
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.form-group input {
  width: 100%;
  padding: 15px 20px;
  border: 2px solid #e0e0e0;
  border-radius: 30px;
  font-size: 16px;
  transition: var(--transition);
  background: white;
}

.form-group input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 4px rgba(67, 97, 238, 0.1);
}

/* Кнопка логина — на всю ширину */
.login-container .btn {
  width: 100%;
  padding: 15px;
  font-size: 15px;
}

/* Пустая корзина */
.empty-cart {
  text-align: center;
  padding: 60px;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius);
  color: var(--gray-color);
  font-size: 18px;
  border: 2px dashed var(--primary-color);
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

/* ============================
   АДАПТИВНОСТЬ — МОБИЛЬНЫЕ
   ============================ */

/* Планшеты */
@media (max-width: 768px) {
  .container {
    padding: 15px;
  }

  header {
    flex-direction: column;
    gap: 15px;
    text-align: center;
    padding: 15px 20px;
  }

  h1 {
    font-size: 22px;
  }

  .main-nav {
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
  }

  .nav-link {
    padding: 8px 14px;
    font-size: 13px;
  }

  .cart-item {
    flex-direction: column;
    gap: 15px;
    text-align: center;
    padding: 20px;
  }

  .cart-item-actions {
    flex-wrap: wrap;
    justify-content: center;
  }

  .login-container {
    margin: 40px auto;
    padding: 30px 25px;
  }

  .product-image {
    height: 150px;
  }

  .image-placeholder {
    font-size: 48px;
  }

  .product-title {
    font-size: 16px;
  }

  .product-price {
    font-size: 20px;
  }

  .buy-btn {
    font-size: 16px;
    padding: 15px;
  }

  #balance {
    font-size: 26px;
  }
}

/* Мобильные телефоны */
@media (max-width: 480px) {
  .container {
    padding: 10px;
  }

  header {
    padding: 12px 15px;
    border-radius: 10px;
    margin-bottom: 20px;
  }

  h1 {
    font-size: 20px;
  }

  .login-container {
    margin: 20px auto;
    padding: 25px 20px;
    border-radius: 16px;
  }

  .login-container h1 {
    font-size: 22px;
    margin-bottom: 12px;
  }

  .login-info {
    font-size: 13px;
    margin-bottom: 22px;
  }

  .form-group {
    margin-bottom: 18px;
  }

  .form-group input {
    padding: 13px 16px;
    font-size: 15px;
  }

  .products-grid {
    grid-template-columns: 1fr;
    gap: 15px;
  }

  .product-card {
    padding: 15px;
  }

  .cart-item {
    padding: 15px;
  }

  .cart-item-info h3 {
    font-size: 16px;
  }

  .cart-item-actions input {
    width: 70px;
    font-size: 14px;
  }

  .balance-info {
    flex-direction: column;
    text-align: center;
    padding: 15px;
    font-size: 15px;
    gap: 8px;
  }

  #balance {
    font-size: 28px;
  }

  .empty-cart {
    padding: 40px 20px;
    font-size: 15px;
  }

  .notification {
    left: 10px;
    right: 10px;
    min-width: unset;
    top: 10px;
  }
}

/* Очень маленькие экраны */
@media (max-width: 360px) {
  .login-container {
    margin: 10px;
    padding: 20px 15px;
  }

  .main-nav {
    gap: 5px;
  }

  .nav-link {
    padding: 6px 10px;
    font-size: 12px;
  }
}

/* ============================
   ПРОЧИЕ СТИЛИ
   ============================ */

/* Каталог — заголовок */
.catalog-header {
  text-align: center;
  margin-bottom: 40px;
  animation: fadeIn 0.5s ease;
}

.catalog-header h2 {
  font-size: 36px;
  font-weight: 700;
  background: linear-gradient(135deg, #fff, #f0f0f0);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 10px;
}

.catalog-header p {
  color: rgba(255, 255, 255, 0.8);
  font-size: 18px;
}

@media (max-width: 480px) {
  .catalog-header h2 {
    font-size: 26px;
  }

  .catalog-header p {
    font-size: 15px;
  }
}

/* Бейдж */
.product-badge {
  position: absolute;
  top: 15px;
  right: 15px;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  color: white;
  padding: 5px 15px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  z-index: 1;
  box-shadow: 0 3px 10px rgba(67, 97, 238, 0.3);
  animation: pulse 2s infinite;
}

/* Изображение товара */
.product-image {
  width: 100%;
  height: 180px;
  display: flex;
  justify-content: center;
  align-items: center;
  margin-bottom: 15px;
  background: linear-gradient(135deg, #f5f7fa, #e9ecef);
  border-radius: 15px;
  overflow: hidden;
}

.image-placeholder {
  font-size: 64px;
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

/* Информация о товаре */
.product-info {
  flex: 1;
  display: flex;
  flex-direction: column;
}

.product-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--dark-color);
}

.product-description {
  font-size: 14px;
  color: var(--gray-color);
  margin-bottom: 15px;
  line-height: 1.4;
}

/* Цена */
.product-price {
  font-size: 24px;
  font-weight: 700;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin: 10px 0;
  display: flex;
  align-items: center;
  gap: 10px;
}

.old-price {
  font-size: 16px;
  color: var(--gray-color);
  text-decoration: line-through;
  background: none;
  -webkit-text-fill-color: var(--gray-color);
}

/* Наличие */
.product-stock {
  margin-bottom: 15px;
}

.stock-status {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 12px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
}

.in-stock {
  background: rgba(6, 214, 160, 0.1);
  color: #06d6a0;
  border: 1px solid rgba(6, 214, 160, 0.3);
}

.low-stock {
  background: rgba(255, 209, 102, 0.1);
  color: #ffd166;
  border: 1px solid rgba(255, 209, 102, 0.3);
}

.out-of-stock {
  background: rgba(239, 71, 111, 0.1);
  color: #ef476f;
  border: 1px solid rgba(239, 71, 111, 0.3);
}

/* Кнопка добавления */
.add-to-cart {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px;
  font-size: 14px;
}

.btn-icon {
  font-size: 16px;
}

.add-to-cart:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background: linear-gradient(135deg, #95a5a6, #7f8c8d);
}

.add-to-cart:disabled:hover {
  transform: none;
  box-shadow: none;
}

.add-to-cart:disabled::before {
  display: none;
}

@keyframes addToCart {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.1);
  }
  100% {
    transform: scale(1);
  }
}

.add-to-cart:active {
  animation: addToCart 0.3s ease;
}

/* Уведомления */
.notification {
  position: fixed;
  top: 20px;
  right: 20px;
  padding: 15px 25px;
  border-radius: 30px;
  background: white;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
  transform: translateX(400px);
  transition: transform 0.3s ease;
  z-index: 1000;
  font-weight: 500;
  min-width: 250px;
  text-align: center;
}

.notification.show {
  transform: translateX(0);
}

.notification-success {
  background: linear-gradient(135deg, #06d6a0, #1b9aaa);
  color: white;
}

.notification-error {
  background: linear-gradient(135deg, #ef476f, #d62828);
  color: white;
}

.notification-info {
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  color: white;
}

/* Загрузка */
.loading-spinner {
  width: 50px;
  height: 50px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 1s ease-in-out infinite;
  margin: 50px auto;
}

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

/* Ошибка */
.error-message {
  text-align: center;
  padding: 40px;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius);
  color: white;
  font-size: 18px;
  border: 1px solid rgba(239, 71, 111, 0.3);
}