/**
 * Layout System
 *
 * Containers, grid utilities, and section structure.
 * Mobile-first responsive design.
 */

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

.container {
  width: var(--content-width);
  max-width: var(--container-xl);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

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

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

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

/* ========================================
   SECTIONS
   ======================================== */

.section {
  padding-top: var(--section-gap);
  padding-bottom: var(--section-gap);
}

.section--hero {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: var(--space-20);
  padding-bottom: var(--space-12);
}

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

.section--accent {
  background-color: var(--color-bg-accent);
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-12);
}

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

.section__subtitle {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  max-width: 60ch;
  margin-left: auto;
  margin-right: auto;
}

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

.grid {
  display: grid;
  gap: var(--space-6);
}

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

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

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

@media (min-width: 640px) {
  .grid--2 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid--3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 768px) {
  .grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 1024px) {
  .grid--4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

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

.grid--auto-sm {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

/* Gap variations */
.grid--gap-sm { gap: var(--space-4); }
.grid--gap-lg { gap: var(--space-8); }
.grid--gap-xl { gap: var(--space-12); }

/* ========================================
   FLEXBOX LAYOUTS
   ======================================== */

.row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}

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

.row--between {
  justify-content: space-between;
  align-items: center;
}

.row--end {
  justify-content: flex-end;
}

.col {
  flex: 1;
  min-width: 0;
}

.col--auto {
  flex: 0 0 auto;
}

/* ========================================
   HEADER / NAVIGATION
   ======================================== */

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-sticky);
  background-color: rgba(255, 254, 249, 0.9);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border-light);
  transition: var(--transition-all);
}

.header--scrolled {
  box-shadow: var(--shadow-sm);
}

.header__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 4rem;
}

@media (min-width: 768px) {
  .header__inner {
    height: 5rem;
  }
}

.header__logo {
  font-family: var(--font-heading);
  font-weight: var(--font-bold);
  font-size: var(--text-xl);
  color: var(--color-text-primary);
  text-decoration: none;
  transition: var(--transition-colors);
}

.header__logo:hover {
  color: var(--ocean);
}

.header__nav {
  display: none;
}

@media (min-width: 768px) {
  .header__nav {
    display: flex;
    gap: var(--space-8);
  }
}

.header__link {
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: var(--transition-colors);
  position: relative;
}

.header__link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--ocean);
  transition: width var(--duration-normal) var(--ease-out);
}

.header__link:hover {
  color: var(--ocean);
}

.header__link:hover::after {
  width: 100%;
}

/* Mobile menu toggle */
.header__toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 28px;
  height: 28px;
  cursor: pointer;
}

@media (min-width: 768px) {
  .header__toggle {
    display: none;
  }
}

.header__toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text-primary);
  transition: var(--transition-all);
}

.header__toggle.is-active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.header__toggle.is-active span:nth-child(2) {
  opacity: 0;
}

.header__toggle.is-active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile navigation */
.mobile-nav {
  position: fixed;
  top: 4rem;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--color-bg-primary);
  z-index: var(--z-overlay);
  padding: var(--space-8);
  transform: translateX(100%);
  transition: transform var(--duration-normal) var(--ease-out);
}

.mobile-nav.is-open {
  transform: translateX(0);
}

.mobile-nav__link {
  display: block;
  font-size: var(--text-2xl);
  font-weight: var(--font-semibold);
  color: var(--color-text-primary);
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-border);
  transition: var(--transition-colors);
}

.mobile-nav__link:hover {
  color: var(--ocean);
}

/* ========================================
   FOOTER
   ======================================== */

.footer {
  background-color: var(--midnight);
  color: var(--white);
  padding: var(--space-12) 0 var(--space-6);
}

.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-6);
  text-align: center;
}

@media (min-width: 768px) {
  .footer__inner {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

.footer__brand {
  font-family: var(--font-heading);
  font-weight: var(--font-bold);
  font-size: var(--text-xl);
}

.footer__links {
  display: flex;
  gap: var(--space-6);
}

.footer__link {
  color: rgba(255, 254, 249, 0.7);
  transition: var(--transition-colors);
}

.footer__link:hover {
  color: var(--white);
}

.footer__social {
  display: flex;
  gap: var(--space-4);
}

.footer__social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-full);
  background-color: rgba(255, 254, 249, 0.1);
  color: var(--white);
  transition: var(--transition-all);
}

.footer__social-link:hover {
  background-color: var(--ocean);
  transform: translateY(-2px);
}

.footer__copyright {
  font-size: var(--text-sm);
  color: rgba(255, 254, 249, 0.5);
  padding-top: var(--space-6);
  border-top: 1px solid rgba(255, 254, 249, 0.1);
  text-align: center;
  width: 100%;
}

/* ========================================
   MAIN CONTENT OFFSET
   ======================================== */

.main {
  padding-top: 4rem; /* Header height offset */
}

@media (min-width: 768px) {
  .main {
    padding-top: 5rem;
  }
}

/* ========================================
   TWO COLUMN LAYOUT
   ======================================== */

.split {
  display: grid;
  gap: var(--space-8);
  align-items: center;
}

@media (min-width: 768px) {
  .split {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-12);
  }

  .split--reverse {
    direction: rtl;
  }

  .split--reverse > * {
    direction: ltr;
  }
}

/* ========================================
   STACK (Vertical spacing)
   ======================================== */

.stack {
  display: flex;
  flex-direction: column;
}

.stack--sm { gap: var(--space-2); }
.stack--md { gap: var(--space-4); }
.stack--lg { gap: var(--space-6); }
.stack--xl { gap: var(--space-8); }