/* ============================================
   Строительные калькуляторы — стили
   Адаптивный дизайн, светлая тема
   ============================================ */

:root {
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-secondary: #64748b;
  --color-success: #16a34a;
  --color-error: #dc2626;
  --color-bg: #f8fafc;
  --color-card: #ffffff;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-border: #e2e8f0;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --radius: 8px;
  --radius-lg: 12px;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

/* Тёмная тема — светлые шрифты для читаемости */
html.dark {
  --color-primary: #60a5fa;
  --color-primary-hover: #93c5fd;
  --color-bg: #0f172a;
  --color-card: #1e293b;
  --color-text: #ffffff;
  --color-text-muted: #cbd5e1;
  --color-border: #334155;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
}

html.dark .form-group input,
html.dark .form-group select {
  color: #ffffff;
  background: #334155;
  border-color: #475569;
}

html.dark .form-group select option {
  background: #1e293b;
  color: #ffffff;
}

html.dark .stepper-btn {
  background: #334155;
  border-color: #475569;
  color: #ffffff;
}

html.dark .stepper-btn:hover {
  background: #475569;
}

html.dark .result-value {
  color: #93c5fd;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
  padding: 0 1rem;
}

/* Header */
.header {
  background: var(--color-card);
  padding: 1.5rem 0;
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  margin: 0;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
}

.tagline {
  margin: 0.25rem 0 1rem;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.nav-link {
  display: inline-block;
  padding: 0.5rem 0.75rem;
  color: var(--color-primary);
  text-decoration: none;
  border-radius: var(--radius);
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
}

.nav-link:hover {
  background: rgba(37, 99, 235, 0.1);
}

/* Переключатель темы */
.theme-toggle {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 44px;
  height: 44px;
  min-width: 44px;
  min-height: 44px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-card);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, transform 0.2s;
  z-index: 10000;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
}

.theme-toggle:hover {
  background: var(--color-bg);
  transform: scale(1.05);
}

.theme-toggle:active {
  transform: scale(0.98);
}

.theme-icon {
  font-size: 1.25rem;
  transition: opacity 0.3s;
}

.theme-icon.moon {
  display: none;
}

html.dark .theme-icon.sun {
  display: none;
}

html.dark .theme-icon.moon {
  display: inline;
}

/* Main */
.main {
  padding: 2rem 0 3rem;
}

.section-title {
  margin: 0 0 0.5rem;
  font-size: 1.25rem;
  font-weight: 600;
}

.section-desc {
  margin: 0 0 1rem;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.calculator-section {
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--color-border);
}

.calculator-section:last-of-type {
  border-bottom: none;
}

.calculator-placeholder {
  opacity: 0.7;
}

.calculator-card {
  background: var(--color-card);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-md);
}

/* Forms */
.calculator-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.form-group label {
  font-weight: 500;
  font-size: 0.9rem;
}

.form-group input,
.form-group select {
  padding: 0.75rem 1rem;
  font-size: 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-card);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

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

.error-msg {
  font-size: 0.8rem;
  color: var(--color-error);
  min-height: 1.2em;
}

/* Поле с кнопками +/− */
.input-with-stepper {
  display: flex;
  align-items: stretch;
  gap: 0;
}

.input-with-stepper input {
  flex: 1;
  min-width: 0;
  border-radius: 0;
  text-align: center;
}

.input-with-stepper input::-webkit-outer-spin-button,
.input-with-stepper input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.input-with-stepper input[type="number"] {
  -moz-appearance: textfield;
}

.stepper-btn {
  width: 44px;
  min-width: 44px;
  min-height: 44px;
  flex-shrink: 0;
  padding: 0;
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
  cursor: pointer;
  transition: background 0.2s;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
}

.stepper-btn:first-child {
  border-right: none;
  border-radius: var(--radius) 0 0 var(--radius);
}

.stepper-btn:last-child {
  border-left: none;
  border-radius: 0 var(--radius) var(--radius) 0;
}

.stepper-btn:hover {
  background: var(--color-border);
}

.stepper-btn:active {
  background: var(--color-secondary);
}

/* НДС: переключатель режимов */
.vat-mode-fieldset {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem;
  margin: 0;
}

.vat-mode-legend {
  font-weight: 500;
  font-size: 0.9rem;
  padding: 0 0.5rem;
  margin: 0 0 0.75rem;
}

.vat-mode-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  margin-bottom: 0.5rem;
}

.vat-mode-label:last-of-type {
  margin-bottom: 0;
}

.vat-mode-label input {
  margin: 0;
}

.vat-mode-hint {
  margin: 0.5rem 0 0;
  font-size: 0.85rem;
  color: var(--color-text-muted);
  line-height: 1.4;
}

.result-value-multiline {
  white-space: pre-line;
}

.form-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.25rem;
  font-size: 1rem;
  font-weight: 500;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s, color 0.2s, transform 0.1s;
}

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

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

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

.btn-secondary {
  background: var(--color-bg);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: var(--color-border);
}

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

.btn-outline:hover {
  background: rgba(37, 99, 235, 0.1);
}

/* Result block */
.result-block {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

.result-block.hidden {
  display: none;
}

/* Анимация появления результата */
.result-block.result-animate {
  animation: resultFadeIn 0.5s ease-out;
}

@keyframes resultFadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Подсказки и тултипы */
.has-tooltip {
  cursor: help;
  position: relative;
}

.has-tooltip:hover::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  margin-bottom: 6px;
  padding: 0.5rem 0.75rem;
  background: var(--color-text);
  color: var(--color-card);
  font-size: 0.8rem;
  font-weight: 400;
  white-space: normal;
  max-width: 220px;
  text-align: center;
  border-radius: var(--radius);
  z-index: 10;
  box-shadow: var(--shadow-md);
  animation: tooltipFade 0.2s ease;
}

@keyframes tooltipFade {
  from { opacity: 0; }
  to { opacity: 1; }
}

.result-block h3 {
  margin: 0 0 0.5rem;
  font-size: 1rem;
  font-weight: 600;
}

.result-value {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-primary);
  margin: 0 0 1rem;
}

.result-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

/* Affiliates block */
.affiliates-block {
  margin-top: 1rem;
}

.affiliates-title {
  font-size: 0.9rem;
  font-weight: 600;
  margin: 0 0 0.75rem;
  color: var(--color-text-muted);
}

.affiliates-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 1rem;
}

.affiliate-card {
  background: var(--color-bg);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--color-border);
}

.affiliate-image {
  width: 100%;
  height: 100px;
  object-fit: cover;
  background: var(--color-border);
}

.affiliate-body {
  padding: 0.75rem;
}

.affiliate-name {
  font-weight: 500;
  font-size: 0.9rem;
  margin: 0 0 0.25rem;
}

.affiliate-price {
  font-size: 0.85rem;
  color: var(--color-primary);
  font-weight: 600;
  margin: 0 0 0.5rem;
}

.affiliate-link {
  display: inline-block;
  padding: 0.4rem 0.75rem;
  font-size: 0.85rem;
  background: var(--color-primary);
  color: white;
  text-decoration: none;
  border-radius: var(--radius);
  font-weight: 500;
  transition: background 0.2s;
}

.affiliate-link:hover {
  background: var(--color-primary-hover);
}

/* Feedback */
.feedback-section {
  margin-top: 2rem;
  padding: 1.5rem;
  background: var(--color-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.feedback-section h2 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
}

.feedback-section p {
  margin: 0 0 1rem;
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.feedback-section .btn {
  margin-right: 0.5rem;
  margin-bottom: 0.5rem;
}

/* Footer */
.footer {
  padding: 1.5rem 0;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--color-border);
}

/* Toast для "Скопировано!" */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  padding: 0.75rem 1.5rem;
  background: var(--color-text);
  color: white;
  border-radius: var(--radius);
  font-weight: 500;
  opacity: 0;
  transition: transform 0.3s, opacity 0.3s;
  z-index: 1000;
}

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

/* Print styles */
@media print {
  .header,
  .nav,
  .form-actions,
  .result-actions,
  .affiliates-block,
  .feedback-section,
  .footer,
  .btn {
    display: none !important;
  }

  .calculator-card {
    box-shadow: none;
    border: 1px solid #ccc;
  }

  .result-block {
    border-top: none;
  }
}

/* ============================================
   Адаптивность — мобильные устройства
   ============================================ */

@media (max-width: 480px) {
  .container {
    padding: 0 1rem;
  }

  .header {
    padding: 1rem 0;
  }

  .logo {
    font-size: 1.25rem;
  }

  .nav-list {
    gap: 0.35rem;
  }

  .nav-link {
    padding: 0.4rem 0.6rem;
    font-size: 0.9rem;
  }

  .calculator-card {
    padding: 1rem;
  }

  .form-group input,
  .form-group select {
    padding: 0.85rem 1rem;
    font-size: 16px; /* предотвращает зум на iOS */
  }

  .btn {
    padding: 0.85rem 1.25rem;
    width: 100%;
    justify-content: center;
  }

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

  .form-actions .btn {
    width: 100%;
  }

  .affiliates-grid {
    grid-template-columns: 1fr;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .theme-toggle {
    position: fixed;
    top: 0.75rem;
    right: 0.5rem;
    width: 52px;
    height: 52px;
    min-width: 52px;
    min-height: 52px;
  }

  .header .container {
    padding-right: 3.5rem;
  }

  .stepper-btn {
    width: 52px;
    min-width: 52px;
    min-height: 52px;
  }
}