/**
 * layout.css
 * Сетка, контейнеры, медиазапросы
 * Mobile-first подход
 * Брейкпоинты: 480px / 768px / 1024px / 1280px
 */

/* ===========================
   Container
   =========================== */

.container {
  width: 100%;
  max-width: 1280px;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-md);
  padding-right: var(--spacing-md);
}

.container_narrow {
  max-width: 640px;
}

.container_wide {
  max-width: 1440px;
}

/* ===========================
   Page Layout
   =========================== */

.page {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.page__main {
  flex: 1;
}

/* ===========================
   Section
   =========================== */

.section {
  padding-top: var(--spacing-2xl);
  padding-bottom: var(--spacing-2xl);
}

.section_alt {
  background-color: var(--color-bg-alt);
}

.section__title {
  margin-bottom: var(--spacing-lg);
  font-size: var(--font-size-xl);
  text-align: center;
}

.section__subtitle {
  margin-bottom: var(--spacing-xl);
  color: var(--color-text-muted);
  text-align: center;
}

/* ===========================
   Grid System
   =========================== */

.grid {
  display: grid;
  gap: var(--spacing-md);
}

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

.grid_cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid_cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid_cols-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* ===========================
   Flex Utilities
   =========================== */

.flex {
  display: flex;
}

.flex_column {
  flex-direction: column;
}

.flex_wrap {
  flex-wrap: wrap;
}

.flex_center {
  justify-content: center;
  align-items: center;
}

.flex_between {
  justify-content: space-between;
}

.flex_align-center {
  align-items: center;
}

.flex_align-start {
  align-items: flex-start;
}

.flex_align-end {
  align-items: flex-end;
}

.flex_gap-sm {
  gap: var(--spacing-sm);
}

.flex_gap-md {
  gap: var(--spacing-md);
}

.flex_gap-lg {
  gap: var(--spacing-lg);
}

/* ===========================
   Spacing Utilities
   =========================== */

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.pt-sm { padding-top: var(--spacing-sm); }
.pt-md { padding-top: var(--spacing-md); }
.pt-lg { padding-top: var(--spacing-lg); }
.pt-xl { padding-top: var(--spacing-xl); }

.pb-sm { padding-bottom: var(--spacing-sm); }
.pb-md { padding-bottom: var(--spacing-md); }
.pb-lg { padding-bottom: var(--spacing-lg); }
.pb-xl { padding-bottom: var(--spacing-xl); }

/* ===========================
   Responsive Utilities
   =========================== */

.hide-mobile {
  display: none;
}

.show-mobile {
  display: block;
}

/* ===========================
   Media Queries
   =========================== */

/* Small devices (landscape phones, 480px and up) */
@media (min-width: 480px) {
  .container {
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
  }

  .section {
    padding-top: var(--spacing-2xl);
    padding-bottom: var(--spacing-2xl);
  }

  .section__title {
    font-size: var(--font-size-2xl);
  }

  .grid {
    gap: var(--spacing-lg);
  }

  /* Responsive grid at 480px */
  .grid_cols-2-sm {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {
  .container {
    padding-left: var(--spacing-xl);
    padding-right: var(--spacing-xl);
  }

  .section {
    padding-top: var(--spacing-3xl);
    padding-bottom: var(--spacing-3xl);
  }

  .section__title {
    margin-bottom: var(--spacing-xl);
  }

  .grid {
    gap: var(--spacing-xl);
  }

  /* Responsive grid at 768px */
  .grid_cols-2-md {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid_cols-3-md {
    grid-template-columns: repeat(3, 1fr);
  }

  /* Responsive visibility */
  .hide-mobile {
    display: block;
  }

  .show-mobile {
    display: none;
  }

  .hide-tablet {
    display: none;
  }
}

/* Large devices (desktops, 1024px and up) */
@media (min-width: 1024px) {
  .section__title {
    font-size: var(--font-size-2xl);
  }

  /* Responsive grid at 1024px */
  .grid_cols-2-lg {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid_cols-3-lg {
    grid-template-columns: repeat(3, 1fr);
  }

  .grid_cols-4-lg {
    grid-template-columns: repeat(4, 1fr);
  }

  .hide-tablet {
    display: block;
  }

  .hide-desktop {
    display: none;
  }
}

/* Extra large devices (wide screens, 1280px and up) */
@media (min-width: 1280px) {
  .container {
    padding-left: var(--spacing-2xl);
    padding-right: var(--spacing-2xl);
  }

  .section {
    padding-top: var(--spacing-3xl);
    padding-bottom: var(--spacing-3xl);
  }

  .section__title {
    font-size: var(--font-size-3xl);
  }

  /* Responsive grid at 1280px */
  .grid_cols-3-xl {
    grid-template-columns: repeat(3, 1fr);
  }

  .grid_cols-4-xl {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ===========================
   Chat Page Layout
   =========================== */

/* Body modifier for chat page */
.body_chat {
  overflow: hidden;
}

/* Chat page container - sidebar + chat area */
.chat-page {
  display: flex;
  height: calc(100vh - 60px); /* Subtract header height */
  overflow: hidden;
}

/* Mobile: only chat visible, sidebar is overlay */
@media (max-width: 767px) {
  .chat-page {
    flex-direction: column;
  }

  .chat-page > .chat {
    flex: 1;
    width: 100%;
    height: 100%;
    border-radius: 0;
    border: none;
  }
}

/* Tablet and up (768px) */
@media (min-width: 768px) {
  .chat-page {
    height: calc(100vh - 70px);
  }

  .chat-page > .chat {
    flex: 1;
    height: 100%;
    min-width: 0; /* Allow shrinking */
    border-radius: 0;
    border-top: none;
    border-bottom: none;
    border-right: none;
  }
}

/* Desktop (1024px) */
@media (min-width: 1024px) {
  .chat-page {
    height: calc(100vh - 80px);
  }
}