/* ==========================================================================
   NIKOLAS LEONIDIS PORTFOLIO — RESPONSIVE STYLESHEET
   Mobile-first media queries and off-canvas navigation drawer
   ========================================================================== */

/* 1. Mobile Navigation Toggle & Off-canvas Drawer */
.mobile-nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.6rem;
  cursor: pointer;
  color: var(--text);
}

.hamburger-box {
  width: 22px;
  height: 16px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.hamburger-inner,
.hamburger-inner::before,
.hamburger-inner::after {
  width: 100%;
  height: 2px;
  background-color: var(--text);
  border-radius: 2px;
  transition: transform var(--transition-fast);
}

/* Mobile Off-canvas Drawer Overlay */
.mobile-nav-drawer {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 9999;
  visibility: hidden;
  opacity: 0;
  transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.mobile-nav-drawer.is-active {
  visibility: visible;
  opacity: 1;
}

.mobile-nav-backdrop {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(32, 32, 29, 0.6);
  backdrop-filter: blur(4px);
}

.mobile-nav-content {
  position: absolute;
  top: 0;
  right: 0;
  width: 85%;
  max-width: 380px;
  height: 100%;
  background-color: var(--bg);
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.15);
  transform: translateX(100%);
  transition: transform var(--transition-normal);
  overflow-y: auto;
}

.mobile-nav-drawer.is-active .mobile-nav-content {
  transform: translateX(0);
}

.mobile-nav-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.mobile-nav-close {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.4rem;
  color: var(--text);
  cursor: pointer;
}

.mobile-nav-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  margin-top: 2rem;
}

.mobile-nav-link {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
  display: block;
}

.mobile-nav-link.active {
  color: var(--primary-dark);
}

.mobile-nav-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.mobile-nav-contact {
  margin-top: 1.25rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Body Scroll Locking when Mobile Nav is Open */
body.nav-open {
  overflow: hidden !important;
}

/* 2. Breakpoint: Laptop / Medium Screen (1025px - 1439px) */
@media (min-width: 1025px) and (max-width: 1439px) {
  .hero-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
    gap: clamp(1.5rem, 3vw, 2.5rem);
  }
}

/* 3. Breakpoint: Tablet Large (Max Width: 1024px) */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .hero-visual {
    max-width: 580px;
    margin: 0 auto;
    width: 100%;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
  }
}

/* 4. Breakpoint: Tablet & Mobile (Max Width: 768px) */
@media (max-width: 768px) {
  .desktop-nav {
    display: none;
  }
  
  .mobile-nav-toggle {
    display: block;
  }

  .header-cta {
    display: none;
  }

  .hero-title {
    font-size: clamp(2rem, 6.5vw, 2.75rem);
  }

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

  .hero-visual {
    max-width: 480px;
    margin: 0 auto;
    width: 100%;
  }

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

  .form-row {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

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

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* 5. Breakpoint: Mobile Small (Max Width: 480px) */
@media (max-width: 480px) {
  .container {
    padding-left: 1.25rem;
    padding-right: 1.25rem;
  }

  .hero-card-stats-grid {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  .hero-ctas {
    flex-direction: column;
    width: 100%;
  }

  .hero-ctas .btn {
    width: 100%;
  }

  .timeline {
    padding-left: 1.5rem;
  }

  .timeline-marker {
    left: -1.5rem;
  }

  .filter-bar {
    justify-content: flex-start;
    overflow-x: auto;
    padding-bottom: 0.5rem;
  }

  .filter-btn {
    white-space: nowrap;
  }
}