/* ===== TOKENS & BASE STYLES ===== */
:root {
  /* Палитра */
  --color-bg: #fff;
  --color-fg: #0b0b0b;
  --color-muted: #666;
  --color-primary: #0a84ff;
  --color-danger: #b00020;
  --color-success: #00a650;

  /* Типографика */
  --font-body: system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  
  /* Размеры */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 40px;
  
  /* Скругления и тени */
  --radius: 12px;
  --shadow: 0 1px 2px rgba(0,0,0,.08), 0 8px 24px rgba(0,0,0,.08);
  
  /* Цветовая схема по умолчанию */
  color-scheme: light;
}

/* Тёмная тема */
body.theme-dark {
  --color-bg: #0b0b0b;
  --color-fg: #f5f5f5;
  --color-muted: #aaa;
  --color-primary: #6aa2ff;
  color-scheme: dark;
}

/* ===== RESET & BASE ===== */
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body { 
  background: var(--color-bg); 
  color: var(--color-fg); 
  font-family: var(--font-body); 
  line-height: 1.5;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Плавная прокрутка */
html { scroll-behavior: smooth; }

/* Базовые стили для медиа */
img, video { max-width: 100%; height: auto; display: block; }

/* Наследование шрифтов для форм */
button, input, select, textarea { font: inherit; color: inherit; }

/* ===== LAYOUT & UTILITIES ===== */
.container {
  width: min(100% - 2 * var(--space-4), 1120px);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

.section {
  padding-block: var(--space-5);
}

.section__title {
  margin: 0 0 var(--space-3);
  font-size: 1.75rem;
}

/* ===== HEADER & NAVIGATION (БЭМ) ===== */
.site-header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-muted);
  padding: var(--space-3) 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header__container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: relative;
}

.site-header__brand {
  font-size: 1.5rem;
  font-weight: bold;
  text-decoration: none;
  color: var(--color-fg);
}

.site-nav__list {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: var(--space-4);
}

.site-nav__link {
  text-decoration: none;
  color: var(--color-muted);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius);
  transition: all 0.2s ease;
}

/* Состояния ссылок (LVHA) */
.site-nav__link:link { color: var(--color-muted); }
.site-nav__link:visited { color: var(--color-muted); }
.site-nav__link:hover { 
  color: var(--color-primary); 
  background: rgba(10, 132, 255, 0.1);
}
.site-nav__link:active { 
  color: var(--color-primary); 
  transform: translateY(1px);
}

.site-nav__link--active {
  color: var(--color-primary);
  background: rgba(10, 132, 255, 0.1);
  font-weight: 600;
}

.site-nav__link--cta {
  background: var(--color-primary);
  color: white !important;
}

.site-nav__link--cta:hover {
  background: #0070cc;
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

/* ===== BREADCRUMBS (БЭМ) ===== */
.breadcrumbs {
  padding: var(--space-3) 0;
  margin-bottom: var(--space-4);
}

.breadcrumbs__list {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.breadcrumbs__item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.breadcrumbs__link {
  text-decoration: none;
  color: var(--color-muted);
  font-size: 0.9rem;
}

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

.breadcrumbs__item:not(:last-child)::after {
  content: "→";
  color: var(--color-muted);
}

.breadcrumbs__current {
  color: var(--color-fg);
  font-weight: 600;
}

/* ===== FORM STYLES (БЭМ) ===== */
.form {
  max-width: 600px;
  margin: 0 auto;
  padding: var(--space-4);
  background: var(--color-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.form__group {
  margin-bottom: var(--space-4);
}

.form__label {
  display: block;
  margin-bottom: var(--space-2);
  font-weight: 500;
  color: var(--color-fg);
}

.form__control {
  width: 100%;
  padding: var(--space-3);
  border: 1px solid var(--color-muted);
  border-radius: var(--radius);
  background: var(--color-bg);
  color: var(--color-fg);
  transition: all 0.2s ease;
}

.form__control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(10, 132, 255, 0.1);
}

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

.form__error {
  color: var(--color-danger);
  font-size: 0.875rem;
  margin-top: var(--space-1);
  display: none;
}

.form__control[aria-invalid="true"] ~ .form__error {
  display: block;
}

.form__actions {
  display: flex;
  gap: var(--space-3);
  margin-top: var(--space-4);
  justify-content: flex-end;
}

/* ===== BUTTON STYLES ===== */
.btn {
  padding: var(--space-3) var(--space-4);
  border: none;
  border-radius: var(--radius);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
}

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

.btn--primary:hover {
  background: #0070cc;
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}

.btn--secondary {
  background: transparent;
  color: var(--color-fg);
  border: 1px solid var(--color-muted);
}

.btn--secondary:hover {
  background: rgba(0, 0, 0, 0.05);
}

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

.btn--danger:hover {
  background: #8b0000;
}

/* ===== MODAL STYLES (БЭМ) ===== */
.modal {
  padding: var(--space-4);
  border: none;
  border-radius: var(--radius);
  background: var(--color-bg);
  color: var(--color-fg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  max-width: 500px;
  width: 90vw;
}

.modal::backdrop {
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(2px);
}

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

.modal__title {
  margin: 0;
  font-size: 1.5rem;
}

.modal__close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-muted);
  padding: var(--space-1);
}

.modal__close:hover {
  color: var(--color-fg);
}

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

.modal__footer {
  display: flex;
  gap: var(--space-3);
  justify-content: flex-end;
}

/* ===== HERO SECTION WITH BACKGROUND ===== */
.hero {
  background: 
    linear-gradient(to top, rgba(0,0,0,.55), rgba(0,0,0,.15)),
    url("assets/hero-1920.jpg") center/cover no-repeat;
  color: white;
  padding: clamp(2rem, 6vw, 6rem) 1rem;
  border-radius: var(--radius);
  margin-bottom: var(--space-5);
  text-align: center;
}

.hero__title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  margin: 0 0 var(--space-3);
  text-shadow: 0 2px 4px rgba(0,0,0,0.5);
}

.hero__subtitle {
  font-size: clamp(1rem, 3vw, 1.5rem);
  margin: 0;
  opacity: 0.9;
  text-shadow: 0 1px 2px rgba(0,0,0,0.5);
}

/* ===== RESPONSIVE IMAGES ===== */
.responsive-image {
  width: 100%;
  height: auto;
  border-radius: var(--radius);
}

/* Контейнер для адаптивных изображений */
.image-container {
  margin: var(--space-4) 0;
}

/* ===== MEDIA CONTAINER (для видео) ===== */
.media {
  aspect-ratio: 16/9;
  width: min(100%, 960px);
  margin-inline: auto;
  margin: var(--space-4) auto;
}

.media iframe,
.media video {
  width: 100%;
  height: 100%;
  border: 0;
  border-radius: var(--radius);
}

/* ===== FOCUS & ACCESSIBILITY ===== */
:where(a, button, input, select, textarea):focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

:disabled, [aria-disabled="true"] {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Подсветка якоря при переходе */
:target {
  outline: 2px dashed var(--color-primary);
  outline-offset: 4px;
  animation: target-fade 3s ease;
}

@keyframes target-fade {
  0% { background-color: rgba(10, 132, 255, 0.2); }
  100% { background-color: transparent; }
}

/* ===== THEME TOGGLE BUTTON ===== */
.theme-toggle {
  position: fixed;
  top: var(--space-2);
  left: var(--space-2);
  z-index: 1000;
  padding: var(--space-2) var(--space-3);
  background: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: all 0.3s ease;
  font-size: 0.875rem;
}

.theme-toggle:hover {
  transform: translateY(-2px);
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
  .site-header__container {
    flex-direction: column;
    gap: var(--space-3);
  }
  
  .site-nav__list {
    flex-direction: column;
    gap: var(--space-2);
    text-align: center;
  }
  
  .form__actions {
    flex-direction: column;
  }
  
  .modal {
    margin: var(--space-3);
    width: calc(100vw - 2 * var(--space-3));
  }
  
  .theme-toggle {
    position: fixed;
    top: var(--space-2);
    left: var(--space-2);
  }
}

@media (max-width: 480px) {
  :root {
    --space-4: 16px;
    --space-5: 24px;
  }
  
  .container {
    padding-inline: var(--space-2);
  }
  
  .theme-toggle {
    font-size: 0.75rem;
    padding: var(--space-1) var(--space-2);
  }
}

/* ===== PRINT STYLES ===== */
@media print {
  .site-nav, .theme-toggle, .modal {
    display: none !important;
  }
  
  body {
    background: white !important;
    color: black !important;
  }
  
  a {
    color: black !important;
    text-decoration: underline;
  }
}