/**
 * Layout System
 * Containers, grid, flexbox utilities, and spacing
 */

/* ========================================
   CONTAINERS
   ======================================== */

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

.container-narrow {
  max-width: var(--max-width-narrow);
}

.container-text {
  max-width: var(--max-width-text);
}

.container-fluid {
  max-width: none;
  width: 100%;
}

/* Activity Container (Full-width for content) */
.activity-container {
  width: 100%;
  min-height: 100vh;
  background-color: var(--color-background);
}

/* ========================================
   CONTENT WRAPPERS
   ======================================== */

.sequential-content {
  width: 100%;
  max-width: var(--max-width-content);
  margin: 0 auto;
  padding: var(--spacing-lg);
}

/* Content type specific wrappers */
.problem-set-content,
.hexagon-lab-content,
.flexbook-content,
.research-brief-content {
  width: 100%;
}

/* ========================================
   GRID SYSTEM
   ======================================== */

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

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

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

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

/* Responsive grid - collapses to single column on mobile */
@media (max-width: 768px) {
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* Auto-fit grid (fills available space) */
.grid-auto {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* ========================================
   FLEXBOX 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;
  align-items: center;
}

.flex-start {
  justify-content: flex-start;
  align-items: flex-start;
}

.flex-end {
  justify-content: flex-end;
  align-items: flex-end;
}

.flex-1 {
  flex: 1;
}

.flex-grow {
  flex-grow: 1;
}

.flex-shrink {
  flex-shrink: 1;
}

.flex-no-shrink {
  flex-shrink: 0;
}

/* ========================================
   SPACING UTILITIES
   ======================================== */

/* Margin utilities */
.m-0 { margin: 0; }
.mt-0 { margin-top: 0; }
.mr-0 { margin-right: 0; }
.mb-0 { margin-bottom: 0; }
.ml-0 { margin-left: 0; }

.m-sm { margin: var(--spacing-sm); }
.mt-sm { margin-top: var(--spacing-sm); }
.mr-sm { margin-right: var(--spacing-sm); }
.mb-sm { margin-bottom: var(--spacing-sm); }
.ml-sm { margin-left: var(--spacing-sm); }

.m-md { margin: var(--spacing-md); }
.mt-md { margin-top: var(--spacing-md); }
.mr-md { margin-right: var(--spacing-md); }
.mb-md { margin-bottom: var(--spacing-md); }
.ml-md { margin-left: var(--spacing-md); }

.m-lg { margin: var(--spacing-lg); }
.mt-lg { margin-top: var(--spacing-lg); }
.mr-lg { margin-right: var(--spacing-lg); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.ml-lg { margin-left: var(--spacing-lg); }

.m-xl { margin: var(--spacing-xl); }
.mt-xl { margin-top: var(--spacing-xl); }
.mr-xl { margin-right: var(--spacing-xl); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.ml-xl { margin-left: var(--spacing-xl); }

/* Auto margins */
.mx-auto {
  margin-left: auto;
  margin-right: auto;
}

/* Padding utilities */
.p-0 { padding: 0; }
.pt-0 { padding-top: 0; }
.pr-0 { padding-right: 0; }
.pb-0 { padding-bottom: 0; }
.pl-0 { padding-left: 0; }

.p-sm { padding: var(--spacing-sm); }
.pt-sm { padding-top: var(--spacing-sm); }
.pr-sm { padding-right: var(--spacing-sm); }
.pb-sm { padding-bottom: var(--spacing-sm); }
.pl-sm { padding-left: var(--spacing-sm); }

.p-md { padding: var(--spacing-md); }
.pt-md { padding-top: var(--spacing-md); }
.pr-md { padding-right: var(--spacing-md); }
.pb-md { padding-bottom: var(--spacing-md); }
.pl-md { padding-left: var(--spacing-md); }

.p-lg { padding: var(--spacing-lg); }
.pt-lg { padding-top: var(--spacing-lg); }
.pr-lg { padding-right: var(--spacing-lg); }
.pb-lg { padding-bottom: var(--spacing-lg); }
.pl-lg { padding-left: var(--spacing-lg); }

.p-xl { padding: var(--spacing-xl); }
.pt-xl { padding-top: var(--spacing-xl); }
.pr-xl { padding-right: var(--spacing-xl); }
.pb-xl { padding-bottom: var(--spacing-xl); }
.pl-xl { padding-left: var(--spacing-xl); }

/* ========================================
   DISPLAY UTILITIES
   ======================================== */

.d-none { display: none; }
.d-block { display: block; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }

/* Responsive display utilities */
@media (max-width: 480px) {
  .d-mobile-none { display: none; }
  .d-mobile-block { display: block; }
}

@media (min-width: 481px) and (max-width: 768px) {
  .d-tablet-none { display: none; }
  .d-tablet-block { display: block; }
}

@media (min-width: 769px) {
  .d-desktop-none { display: none; }
  .d-desktop-block { display: block; }
}

/* ========================================
   TEXT ALIGNMENT
   ======================================== */

.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-justify { text-align: justify; }

/* ========================================
   POSITIONING
   ======================================== */

.position-relative { position: relative; }
.position-absolute { position: absolute; }
.position-fixed { position: fixed; }
.position-sticky { position: sticky; }

/* ========================================
   WIDTH UTILITIES
   ======================================== */

.w-100 { width: 100%; }
.w-75 { width: 75%; }
.w-50 { width: 50%; }
.w-25 { width: 25%; }

.w-auto { width: auto; }

/* ========================================
   HEIGHT UTILITIES
   ======================================== */

.h-100 { height: 100%; }
.h-auto { height: auto; }

.min-h-screen { min-height: 100vh; }

/* ========================================
   OVERFLOW
   ======================================== */

.overflow-auto { overflow: auto; }
.overflow-hidden { overflow: hidden; }
.overflow-scroll { overflow: scroll; }
.overflow-x-auto { overflow-x: auto; }
.overflow-y-auto { overflow-y: auto; }

/* ========================================
   VISIBILITY
   ======================================== */

.visible { visibility: visible; }
.invisible { visibility: hidden; }

.opacity-0 { opacity: 0; }
.opacity-50 { opacity: 0.5; }
.opacity-100 { opacity: 1; }

/* ========================================
   RESPONSIVE CONTAINERS
   ======================================== */

@media (max-width: 480px) {
  .container,
  .sequential-content {
    padding-left: var(--spacing-md);
    padding-right: var(--spacing-md);
  }
}

@media (min-width: 481px) and (max-width: 768px) {
  .container,
  .sequential-content {
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
  }
}

/* ========================================
   SECTION SPACING
   ======================================== */

.section {
  padding: var(--spacing-section) 0;
}

.section-sm {
  padding: var(--spacing-lg) 0;
}

.section-lg {
  padding: var(--spacing-xxl) 0;
}

/* ========================================
   DIVIDERS
   ======================================== */

.divider {
  height: 1px;
  background-color: var(--color-border);
  margin: var(--spacing-lg) 0;
  border: none;
}

.divider-thick {
  height: 2px;
  background-color: var(--color-border-dark);
}

/* ========================================
   ASPECT RATIOS (for embedded content)
   ======================================== */

.aspect-16-9 {
  position: relative;
  padding-bottom: 56.25%; /* 9/16 = 0.5625 */
}

.aspect-4-3 {
  position: relative;
  padding-bottom: 75%; /* 3/4 = 0.75 */
}

.aspect-1-1 {
  position: relative;
  padding-bottom: 100%;
}

.aspect-16-9 > *,
.aspect-4-3 > *,
.aspect-1-1 > * {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}