/* ============================================
   RESPONSIVE BREAKPOINTS
   ============================================ */

/* ============ TABLET (768px - 1024px) ============ */
@media (max-width: 1024px) {
  :root {
    --section-pad: 80px;
  }

  .nav__links { display: none; }
  .hamburger { display: flex; }

  .about {
    grid-template-columns: 200px 1fr;
    gap: 40px;
  }

  .contact {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .contact__form { padding: 28px; }

  .timeline::before { left: 20px; }

  .timeline__item,
  .timeline__item:nth-child(odd),
  .timeline__item:nth-child(even) {
    width: 100%;
    left: 0;
    text-align: left;
    padding-left: 56px;
    padding-right: 0;
  }

  .timeline__item:nth-child(odd) .timeline__dot,
  .timeline__item:nth-child(even) .timeline__dot {
    left: 12px;
    right: auto;
  }

  /* Fix border sides for single-column timeline */
  .timeline__item:nth-child(odd) .timeline__card { border-right: none; }
  .timeline__item:nth-child(odd).timeline__item--education .timeline__card { border-left: 3px solid rgba(0, 108, 250, 0.4); }
  .timeline__item:nth-child(odd).timeline__item--work .timeline__card { border-left: 3px solid rgba(0, 237, 100, 0.4); }
  .timeline__item:nth-child(odd).timeline__item--entrepreneurship .timeline__card { border-left: 3px solid rgba(177, 255, 5, 0.35); }

  .footer__content {
    flex-direction: column;
    text-align: center;
  }

  .footer__nav { justify-content: center; }
}

/* ============ MOBILE (max-width: 768px) ============ */
@media (max-width: 768px) {
  :root {
    --section-pad: 72px;
  }

  .container { padding: 0 20px; }
  .nav { padding: 12px 20px; }

  .about {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .about__photo {
    display: flex;
    justify-content: center;
  }

  .about__photo-frame {
    width: 180px;
    height: 180px;
  }

  .about__stats { grid-template-columns: repeat(2, 1fr); }
  .about__lead { font-size: 1.3rem; }

  .projects-grid { grid-template-columns: 1fr; }
  .project-card--featured { grid-column: 1; }
  .project-card--featured .project-card__diagram { height: 180px; }
  .project-card__metrics { gap: 12px; flex-wrap: wrap; }
  .project-card__metric-value { font-size: 1rem; }
  .project-ecosystem { flex-direction: column; gap: 8px; padding: 12px 16px; }
  .project-ecosystem__items { flex-wrap: wrap; justify-content: center; }
  .education-grid { grid-template-columns: 1fr; }
  .skills-grid { grid-template-columns: 1fr; }

  .book-card { min-width: 180px; max-width: 180px; }
  .book-card__cover { height: 240px; }

  .section__subtitle { margin-bottom: 40px; }

  .skill-group { padding: 24px; }
  .contact__form { padding: 24px; }
}

/* ============ SMALL MOBILE (max-width: 375px) ============ */
@media (max-width: 375px) {
  :root {
    --section-pad: 56px;
  }

  .container { padding: 0 16px; }
  .hero__name-line { font-size: 2.5rem; }
  .hero__cta { flex-direction: column; align-items: center; }
  .btn { width: 100%; justify-content: center; }
  .about__stats { grid-template-columns: repeat(2, 1fr); gap: 10px; }
  .stat__number { font-size: 2rem; }
  .stat { padding: 16px; }

  .timeline__item,
  .timeline__item:nth-child(odd),
  .timeline__item:nth-child(even) {
    padding-left: 44px;
  }

  .timeline::before { left: 14px; }

  .timeline__item:nth-child(odd) .timeline__dot,
  .timeline__item:nth-child(even) .timeline__dot { left: 6px; }

  .timeline__dot { width: 14px; height: 14px; }
  .footer__nav { flex-wrap: wrap; gap: 12px; }
  .contact__form { padding: 20px; }
}

/* ============ LARGE DESKTOP (1440px+) ============ */
@media (min-width: 1440px) {
  :root {
    --container-max: 1280px;
    --section-pad: 140px;
  }
}