/**
 * 📐 LAYOUT SYSTEM
 * 12-column grid, spacing utilities, responsive structure
 * Version: 2.0 - Business-Ready Streamline
 * 
 * Dependencies: design-tokens.css
 * Usage: Import after design-tokens.css
 * <link rel="stylesheet" href="/layout.css">
 */

/* ========================================
   GLOBAL BOX MODEL
   ======================================== */

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

html {
  font-size: 18px; /* Improved base font size */
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-sans);
  background: var(--bg-base);
  color: var(--color-white);
  line-height: var(--leading-relaxed);
  min-height: 100vh;
}

/* ========================================
   PAGE STRUCTURE
   Hero → Summary → Details → CTA
   ======================================== */

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

.page-header {
  /* Reserved for future navigation */
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--border-color-subtle);
}

.page-main {
  flex: 1;
  padding: var(--space-8) 0;
}

.page-footer {
  padding: var(--space-6) 0;
  border-top: 1px solid var(--border-color-subtle);
  margin-top: var(--space-16);
  text-align: center;
  color: var(--color-gray-500);
  font-size: var(--text-sm);
}

/* ========================================
   CONTAINER SYSTEM
   Centered content with max-widths
   ======================================== */

.container {
  width: 100%;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

.container--sm { max-width: var(--container-sm); }
.container--md { max-width: var(--container-md); }
.container--lg { max-width: var(--container-lg); }
.container--xl { max-width: var(--container-xl); }
.container--2xl { max-width: var(--container-2xl); }

/* Default container size */
.container {
  max-width: var(--container-xl); /* 1280px */
}

@media (min-width: 768px) {
  .container {
    padding-left: var(--space-6);
    padding-right: var(--space-6);
  }
}

@media (min-width: 1024px) {
  .container {
    padding-left: var(--space-8);
    padding-right: var(--space-8);
  }
}

/* ========================================
   12-COLUMN GRID SYSTEM
   ======================================== */

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

/* Column Spans */
.grid-cols-1 { grid-template-columns: repeat(1, 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); }
.grid-cols-5 { grid-template-columns: repeat(5, 1fr); }
.grid-cols-6 { grid-template-columns: repeat(6, 1fr); }
.grid-cols-12 { grid-template-columns: repeat(12, 1fr); }

/* Auto-fit responsive grids */
.grid-auto-fit {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-auto-fill {
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
}

/* Column Spanning */
.col-span-1 { grid-column: span 1; }
.col-span-2 { grid-column: span 2; }
.col-span-3 { grid-column: span 3; }
.col-span-4 { grid-column: span 4; }
.col-span-5 { grid-column: span 5; }
.col-span-6 { grid-column: span 6; }
.col-span-7 { grid-column: span 7; }
.col-span-8 { grid-column: span 8; }
.col-span-9 { grid-column: span 9; }
.col-span-10 { grid-column: span 10; }
.col-span-11 { grid-column: span 11; }
.col-span-12 { grid-column: span 12; }
.col-span-full { grid-column: 1 / -1; }

/* Gap Utilities */
.gap-0 { gap: 0; }
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

/* Responsive Grid (Tablet) */
@media (max-width: 1023px) {
  .md\:grid-cols-1 { grid-template-columns: repeat(1, 1fr); }
  .md\:grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
  .md\:grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
  .md\:grid-cols-4 { grid-template-columns: repeat(4, 1fr); }
  
  .md\:col-span-1 { grid-column: span 1; }
  .md\:col-span-2 { grid-column: span 2; }
  .md\:col-span-3 { grid-column: span 3; }
  .md\:col-span-4 { grid-column: span 4; }
  .md\:col-span-full { grid-column: 1 / -1; }
}

/* Responsive Grid (Mobile) */
@media (max-width: 767px) {
  .sm\:grid-cols-1 { grid-template-columns: repeat(1, 1fr); }
  .sm\:grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
  
  .sm\:col-span-1 { grid-column: span 1; }
  .sm\:col-span-2 { grid-column: span 2; }
  .sm\:col-span-full { grid-column: 1 / -1; }
  
  .sm\:gap-4 { gap: var(--space-4); }
}

/* ========================================
   FLEXBOX UTILITIES
   ======================================== */

.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.flex-row {
  flex-direction: row;
}

.flex-wrap {
  flex-wrap: wrap;
}

.flex-nowrap {
  flex-wrap: nowrap;
}

/* Justify Content */
.justify-start { justify-content: flex-start; }
.justify-end { justify-content: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-around { justify-content: space-around; }

/* Align Items */
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.items-center { align-items: center; }
.items-baseline { align-items: baseline; }
.items-stretch { align-items: stretch; }

/* Flex Grow/Shrink */
.flex-1 { flex: 1; }
.flex-auto { flex: auto; }
.flex-none { flex: none; }

/* Gap */
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

/* ========================================
   SPACING UTILITIES
   Margin & Padding
   ======================================== */

/* Margin */
.m-0 { margin: 0; }
.m-1 { margin: var(--space-1); }
.m-2 { margin: var(--space-2); }
.m-3 { margin: var(--space-3); }
.m-4 { margin: var(--space-4); }
.m-6 { margin: var(--space-6); }
.m-8 { margin: var(--space-8); }
.m-auto { margin: auto; }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--space-1); }
.mt-2 { margin-top: var(--space-2); }
.mt-3 { margin-top: var(--space-3); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--space-1); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-3 { margin-bottom: var(--space-3); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }

.ml-0 { margin-left: 0; }
.ml-auto { margin-left: auto; }
.mr-0 { margin-right: 0; }
.mr-auto { margin-right: auto; }

.mx-auto { margin-left: auto; margin-right: auto; }

/* Padding */
.p-0 { padding: 0; }
.p-1 { padding: var(--space-1); }
.p-2 { padding: var(--space-2); }
.p-3 { padding: var(--space-3); }
.p-4 { padding: var(--space-4); }
.p-6 { padding: var(--space-6); }
.p-8 { padding: var(--space-8); }

.pt-0 { padding-top: 0; }
.pt-4 { padding-top: var(--space-4); }
.pt-6 { padding-top: var(--space-6); }
.pt-8 { padding-top: var(--space-8); }

.pb-0 { padding-bottom: 0; }
.pb-4 { padding-bottom: var(--space-4); }
.pb-6 { padding-bottom: var(--space-6); }
.pb-8 { padding-bottom: var(--space-8); }

.px-4 { padding-left: var(--space-4); padding-right: var(--space-4); }
.px-6 { padding-left: var(--space-6); padding-right: var(--space-6); }
.px-8 { padding-left: var(--space-8); padding-right: var(--space-8); }

.py-4 { padding-top: var(--space-4); padding-bottom: var(--space-4); }
.py-6 { padding-top: var(--space-6); padding-bottom: var(--space-6); }
.py-8 { padding-top: var(--space-8); padding-bottom: var(--space-8); }

/* ========================================
   SECTION SPACING
   Consistent vertical rhythm
   ======================================== */

.section {
  margin-bottom: var(--space-16);
}

.section--sm { margin-bottom: var(--space-8); }
.section--md { margin-bottom: var(--space-12); }
.section--lg { margin-bottom: var(--space-16); }
.section--xl { margin-bottom: var(--space-24); }

/* ========================================
   CARD LAYOUTS
   Standard card grid patterns
   ======================================== */

.card-grid {
  display: grid;
  gap: var(--space-6);
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

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

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

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

@media (max-width: 1023px) {
  .card-grid--3-col,
  .card-grid--4-col {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 767px) {
  .card-grid,
  .card-grid--2-col,
  .card-grid--3-col,
  .card-grid--4-col {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   SPLIT LAYOUTS
   Side-by-side content
   ======================================== */

.split {
  display: grid;
  gap: var(--space-8);
  grid-template-columns: 1fr 1fr;
}

.split--sidebar {
  grid-template-columns: 300px 1fr;
}

.split--sidebar-right {
  grid-template-columns: 1fr 300px;
}

@media (max-width: 1023px) {
  .split,
  .split--sidebar,
  .split--sidebar-right {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   STICKY ELEMENTS
   ======================================== */

.sticky {
  position: sticky;
  top: var(--space-4);
}

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

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

@media (max-width: 767px) {
  .sm\:block { display: block; }
  .sm\:hidden { display: none; }
}

@media (max-width: 1023px) {
  .md\:block { display: block; }
  .md\:hidden { display: none; }
}

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

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

@media (max-width: 767px) {
  .sm\:text-center { text-align: center; }
}

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

.w-full { width: 100%; }
.w-auto { width: auto; }
.w-1\/2 { width: 50%; }
.w-1\/3 { width: 33.333333%; }
.w-2\/3 { width: 66.666667%; }
.w-1\/4 { width: 25%; }
.w-3\/4 { width: 75%; }

.max-w-xs { max-width: 320px; }
.max-w-sm { max-width: 384px; }
.max-w-md { max-width: 448px; }
.max-w-lg { max-width: 512px; }
.max-w-xl { max-width: 576px; }
.max-w-2xl { max-width: 672px; }
.max-w-3xl { max-width: 768px; }
.max-w-4xl { max-width: 896px; }
.max-w-full { max-width: 100%; }

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

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

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

/* ========================================
   POSITION UTILITIES
   ======================================== */

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

/* ========================================
   Z-INDEX UTILITIES
   ======================================== */

.z-0 { z-index: var(--z-base); }
.z-10 { z-index: var(--z-dropdown); }
.z-20 { z-index: var(--z-sticky); }
.z-30 { z-index: var(--z-fixed); }
.z-40 { z-index: var(--z-modal); }
.z-50 { z-index: var(--z-toast); }

/* ========================================
   ROUNDED UTILITIES
   ======================================== */

.rounded-none { border-radius: var(--radius-none); }
.rounded-sm { border-radius: var(--radius-sm); }
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-2xl { border-radius: var(--radius-2xl); }
.rounded-full { border-radius: var(--radius-full); }

/* ========================================
   SHADOW UTILITIES
   ======================================== */

.shadow-none { box-shadow: none; }
.shadow-xs { box-shadow: var(--shadow-xs); }
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }
.shadow-2xl { box-shadow: var(--shadow-2xl); }

/* ========================================
   BORDER UTILITIES
   ======================================== */

.border { border: 1px solid var(--border-color); }
.border-0 { border: none; }
.border-2 { border-width: 2px; border-style: solid; border-color: var(--border-color); }

.border-t { border-top: 1px solid var(--border-color); }
.border-b { border-bottom: 1px solid var(--border-color); }
.border-l { border-left: 1px solid var(--border-color); }
.border-r { border-right: 1px solid var(--border-color); }

.border-primary { border-color: var(--color-primary); }
.border-success { border-color: var(--color-success); }
.border-warning { border-color: var(--color-warning); }
.border-error { border-color: var(--color-error); }

/* ========================================
   CURSOR UTILITIES
   ======================================== */

.cursor-pointer { cursor: pointer; }
.cursor-not-allowed { cursor: not-allowed; }
.cursor-default { cursor: default; }

/* ========================================
   SELECT UTILITIES
   ======================================== */

.select-none { user-select: none; }
.select-text { user-select: text; }
.select-all { user-select: all; }

/* ========================================
   POINTER EVENTS
   ======================================== */

.pointer-events-none { pointer-events: none; }
.pointer-events-auto { pointer-events: auto; }