/* Дизайн-токены (CSS-переменные) */
:root {
  /* Цвета */
  --color-bg: #fff;
  --color-fg: #0b0b0b;
  --color-muted: #666;
  --color-primary: #0a84ff;
  --color-danger: #b00020;
  --color-success: #00c853;
  --color-warning: #ff9800;
  
  /* Шрифты */
  --font-body: system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  
  /* Отступы */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 40px;
  
  /* Скругления */
  --radius: 12px;
  --radius-lg: 16px;
  
  /* Тени */
  --shadow: 0 1px 2px rgba(0,0,0,.08), 0 8px 24px rgba(0,0,0,.08);
  --shadow-lg: 0 15px 35px rgba(0,0,0,0.15);
}

/* Базовые стили */
* { 
  box-sizing: border-box; 
}

html, body { 
  margin: 0; 
  padding: 0; 
}

body {
  font-family: var(--font-body);
  background: var(--color-bg);
  color: var(--color-fg);
  line-height: 1.5;
  padding: var(--space-3);
}

/* Плавная прокрутка к якорям */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 100px;
}

/* Подсветка целевого якоря */
:target {
  background-color: rgba(10, 132, 255, 0.1);
  outline: 2px dashed var(--color-primary);
  outline-offset: var(--space-2);
  animation: target-highlight 2s ease;
  border-left: 4px solid var(--color-primary);
}

@keyframes target-highlight {
  0% {
      background: rgba(10, 132, 255, 0.1);
  }
  50% {
      background: rgba(10, 132, 255, 0.2);
  }
  100% {
      background: rgba(10, 132, 255, 0.1);
  }
}

/* ===== ШАПКА ===== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-muted);
  margin-bottom: var(--space-4);
}

.header__logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--color-primary);
  text-decoration: none;
  transition: opacity 0.3s ease;
}

.header__logo:hover {
  opacity: 0.8;
  animation: bounce 0.6s ease;
}

@keyframes bounce {
  0%, 20%, 60%, 100% {
      transform: translateY(0);
  }
  40% {
      transform: translateY(-5px);
  }
  80% {
      transform: translateY(-2px);
  }
}

/* ===== НАВИГАЦИЯ ===== */
.nav__list {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: var(--space-3);
}

.nav__link {
  position: relative;
  color: var(--color-fg);
  text-decoration: none;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  font-weight: 500;
  display: block;
}

.nav__link:link {
  color: var(--color-fg);
}

.nav__link:visited {
  color: var(--color-muted);
}

.nav__link:hover {
  color: var(--color-primary);
  background: rgba(10, 132, 255, 0.1);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(10, 132, 255, 0.2);
}

.nav__link:active {
  transform: translateY(0);
  box-shadow: 0 2px 6px rgba(10, 132, 255, 0.3);
  transition-duration: 0.1s;
}

.nav__link:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
  background: rgba(10, 132, 255, 0.15);
}

.nav__link--active {
  background: linear-gradient(135deg, var(--color-primary) 0%, #0056b3 100%);
  color: white;
  box-shadow: 0 4px 15px rgba(10, 132, 255, 0.3);
}

.nav__link--active::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: white;
  border-radius: var(--radius) 0 0 var(--radius);
}

/* ===== КНОПКИ ===== */
.button {
  position: relative;
  padding: var(--space-2) var(--space-4);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 1rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  display: inline-block;
  text-align: center;
  overflow: hidden;
}

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

.button--secondary {
  background: var(--color-muted);
  color: white;
}

.button--white {
  background: white;
  color: var(--color-fg);
}

.button:hover {
  filter: brightness(0.95);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.button:active {
  transform: translateY(0);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
  transition-duration: 0.1s;
}

.button:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
  box-shadow: 0 0 0 4px rgba(10, 132, 255, 0.2);
}

.button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
  box-shadow: none !important;
}

/* ===== ОСНОВНОЙ КОНТЕНТ ===== */
.main {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-4) 0;
}

/* ===== ГЕРОЙ СЕКЦИЯ ===== */
.hero {
  text-align: center;
  padding: var(--space-5) 0;
  margin-bottom: var(--space-5);
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border-radius: var(--radius);
}

.hero__title {
  font-size: 2.5rem;
  margin: 0 0 var(--space-3) 0;
  color: white;
}

.hero__subtitle {
  font-size: 1.2rem;
  margin: 0 0 var(--space-4) 0;
  opacity: 0.9;
}

/* ===== СЕКЦИИ ===== */
.section {
  margin-bottom: var(--space-5);
  padding: var(--space-4);
  background: white;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: all 0.3s ease;
}

.section:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.section__title {
  font-size: 1.5rem;
  margin: 0 0 var(--space-3) 0;
  color: var(--color-primary);
}

.section__text {
  margin: 0 0 var(--space-3) 0;
  line-height: 1.6;
}

.section__link {
  position: relative;
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
  overflow: hidden;
}

.section__link::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  transition: left 0.5s;
}

.section__link:hover::before {
  left: 100%;
}

.section__link:hover {
  text-decoration: underline;
}

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

.section--active {
  border-left: 4px solid var(--color-success);
  background: linear-gradient(90deg, rgba(0, 200, 83, 0.05) 0%, transparent 100%);
}

/* ===== КОНТЕНТ ===== */
.content {
  max-width: 800px;
  margin: 0 auto;
}

.content__title {
  font-size: 2rem;
  margin: 0 0 var(--space-4) 0;
  color: var(--color-primary);
}

/* ===== ИЗОБРАЖЕНИЯ ===== */
.image-container {
  margin: var(--space-4) 0;
}

.portfolio-image {
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  transition: all 0.4s ease;
  cursor: pointer;
}

.portfolio-image:hover {
  transform: scale(1.03);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
}

.portfolio-image:active {
  transform: scale(1.01);
}

/* ===== ВИДЕО КОНТЕЙНЕР ===== */
.video-container {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  height: 0;
  margin: var(--space-4) 0;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  background: #000;
  transition: all 0.3s ease;
  animation: fadeInUp 0.6s ease-out;
}

.video-container:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.video-container::before {
  content: 'Загрузка видео...';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: white;
  z-index: 1;
  opacity: 0.7;
}

.video-iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
  border-radius: var(--radius);
  transition: opacity 0.3s ease;
}

.video-iframe:hover {
  opacity: 0.95;
}

.video-iframe.loaded ~ .video-container::before {
  display: none;
}

@keyframes fadeInUp {
  from {
      opacity: 0;
      transform: translateY(30px);
  }
  to {
      opacity: 1;
      transform: translateY(0);
  }
}

/* ===== ПОДВАЛ ===== */
.footer {
  text-align: center;
  padding: var(--space-4) 0;
  border-top: 1px solid var(--color-muted);
  margin-top: var(--space-5);
  color: var(--color-muted);
}

.footer__copyright {
  margin: 0 0 var(--space-2) 0;
}

.footer__contacts {
  margin: 0;
}

.footer__contacts a {
  color: var(--color-primary);
  text-decoration: none;
}

.footer__contacts a:hover {
  text-decoration: underline;
}

/* ===== МОДАЛЬНОЕ ОКНО ===== */
.modal {
  border: none;
  border-radius: var(--radius);
  padding: 0;
  max-width: 90vw;
  width: 500px;
  box-shadow: var(--shadow-lg);
}

.modal::backdrop {
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
}

.modal__content {
  padding: var(--space-4);
}

.modal__title {
  margin: 0 0 var(--space-4) 0;
  color: var(--color-primary);
  font-size: 1.5rem;
}

/* ===== ФОРМЫ ===== */
.form__group {
  margin-bottom: var(--space-3);
}

.form__label {
  display: block;
  margin-bottom: var(--space-1);
  font-weight: 500;
  color: var(--color-fg);
}

.form__input,
.form__select,
.form__textarea {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--color-muted);
  border-radius: var(--radius);
  font-size: 1rem;
  transition: all 0.3s ease;
}

.form__input:hover,
.form__select:hover,
.form__textarea:hover {
  border-color: #a0aec0;
  transform: translateY(-1px);
}

.form__input:focus,
.form__select:focus,
.form__textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(10, 132, 255, 0.1);
  transform: translateY(-1px);
}

.form__input:focus-visible,
.form__select:focus-visible,
.form__textarea:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
}

.form__help {
  display: block;
  margin-top: var(--space-1);
  font-size: 0.875rem;
  color: var(--color-muted);
}

.form__actions {
  display: flex;
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.form__actions .button {
  flex: 1;
}

/* Состояния форм */
:disabled, [aria-disabled="true"] { 
  opacity: .6; 
  cursor: not-allowed; 
}

[aria-invalid="true"] { 
  border-color: var(--color-danger); 
}

.form__error {
  display: block;
  color: var(--color-danger);
  font-size: 0.875rem;
  margin-top: var(--space-1);
}

/* ===== ИНДИКАТОР ПРОГРЕССА СКРОЛЛА ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-success) 100%);
  z-index: 1001;
  transition: width 0.1s ease;
}

/* ===== АДАПТИВНОСТЬ ===== */
@media (max-width: 768px) {
  body {
    padding: var(--space-2);
  }
  
  .header {
    flex-direction: column;
    gap: var(--space-3);
    text-align: center;
  }
  
  .nav__list {
    flex-direction: column;
    gap: var(--space-2);
  }
  
  .hero {
    padding: var(--space-4) var(--space-3);
  }
  
  .hero__title {
    font-size: 2rem;
  }
  
  .section {
    padding: var(--space-3);
    margin-bottom: var(--space-4);
  }
  
  .form__actions {
    flex-direction: column;
  }
  
  .modal {
    width: 95vw;
    margin: var(--space-2);
  }
  
  .video-container {
    margin: var(--space-3) 0;
  }
}

/* ===== ПОДДЕРЖКА PREFERS-REDUCED-MOTION ===== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  
  .section:hover,
  .button:hover,
  .nav__link:hover,
  .portfolio-image:hover,
  .video-container:hover {
    transform: none !important;
  }
  
  .header__logo:hover {
    animation: none;
  }
}

/* ===== УЛУЧШЕННЫЕ ФОКУС-СТИЛИ ===== */
.focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: 4px;
}

button:focus:not(:focus-visible) {
  outline: none;
}

/* ===== ВСПОМОГАТЕЛЬНЫЕ КЛАССЫ ===== */
.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;
}

.text-center {
  text-align: center;
}

.mt-3 {
  margin-top: var(--space-3);
}

.mb-3 {
  margin-bottom: var(--space-3);
}