/* ============================================================
   CSS VARIABLES & RESET
   ============================================================ */
:root {
  --bg: #111111;
  --bg-dark: #0a0a0a;
  --bg-card: #1a1a1a;
  --bg-card-hover: #222222;
  --primary: #ff3b30;
  --secondary: #ff9500;
  --gradient: linear-gradient(135deg, #ff3b30, #ff9500);
  --gradient-text: linear-gradient(90deg, #ff3b30, #ff9500);
  --text: #f4f4f4;
  --text-muted: #888888;
  --text-dim: #555555;
  --border: #2a2a2a;
  --font-heading: 'Teko', sans-serif;
  --font-body: 'Inter', sans-serif;
  --container: 1200px;
  --radius: 4px;
  --transition: 0.3s ease;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.6;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

/* ============================================================
   UTILITIES
   ============================================================ */
.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 2rem;
}

.section {
  padding: 7rem 0;
}

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

.section__header {
  margin-bottom: 2.5rem;
}

.section__label {
  display: block;
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
}

.section__title {
  font-family: var(--font-heading);
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

/* ============================================================
   REVEAL ANIMATIONS
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-block;
  padding: 0.85rem 2rem;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  border-radius: var(--radius);
  transition: var(--transition);
  cursor: pointer;
  border: none;
}

.btn--primary {
  background: var(--gradient);
  color: #fff;
}

.btn--primary:hover {
  opacity: 0.85;
  transform: translateY(-2px);
}

.btn--outline {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}

.btn--outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}

/* ============================================================
   NAVIGATION
   ============================================================ */
#header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1.25rem 0;
  transition: background var(--transition), padding var(--transition);
  background: transparent;
}

#header.scrolled {
  background: rgba(10, 10, 10, 0.95);
  backdrop-filter: blur(10px);
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border);
}

#header.nav-open.scrolled {
  backdrop-filter: none;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 2.5rem;
}

.nav__link {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  transition: color var(--transition);
}

.nav__link:hover,
.nav__link.active {
  color: var(--text);
}

.nav__link--cta {
  color: var(--primary);
}

.nav__link--cta:hover {
  color: var(--secondary);
}

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  position: relative;
  z-index: 200;
}

.nav__toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: var(--transition);
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: 5rem;
}

.hero__bg-text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-heading);
  font-size: clamp(8rem, 20vw, 22rem);
  font-weight: 700;
  letter-spacing: 0.05em;
  color: rgba(255, 255, 255, 0.02);
  white-space: nowrap;
  pointer-events: none;
  user-select: none;
  z-index: 0;
}

.hero__content {
  position: relative;
  z-index: 1;
}

.hero__eyebrow {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.hero__name {
  font-family: var(--font-heading);
  font-size: clamp(4rem, 10vw, 9rem);
  font-weight: 700;
  line-height: 0.9;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
}

.hero__title {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 4vw, 3rem);
  font-weight: 400;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.hero__tagline {
  font-size: 1rem;
  color: var(--text-muted);
  max-width: 480px;
  margin-bottom: 2.5rem;
  line-height: 1.7;
}

.hero__cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero__scroll-indicator {
  position: absolute;
  bottom: 2.5rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-dim);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.hero__scroll-line {
  width: 1px;
  height: 50px;
  background: linear-gradient(to bottom, var(--text-dim), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.3; transform: scaleY(1); }
  50% { opacity: 1; transform: scaleY(1.1); }
}

/* ============================================================
   ABOUT
   ============================================================ */
.about__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
  align-items: center;
}

.about__text p {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 2rem;
}

.about__education {
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
}

.edu-item {
  display: flex;
  gap: 1.5rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--border);
}

.edu-item__year {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  color: var(--primary);
  min-width: 120px;
  padding-top: 2px;
}

.edu-item__degree {
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 0.2rem;
}

.edu-item__institution {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.about__image-frame {
  position: relative;
}

.about__image-frame img {
  width: 100%;
  border-radius: var(--radius);
  filter: grayscale(20%);
  transition: filter var(--transition);
}

.about__image-frame:hover img {
  filter: grayscale(0%);
}

.about__image-accent {
  position: absolute;
  bottom: -1rem;
  right: -1rem;
  width: 60%;
  height: 60%;
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  z-index: -1;
  opacity: 0.4;
}

/* ============================================================
   SKILLS
   ============================================================ */
.skills__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  transition: border-color var(--transition), transform var(--transition);
}

.skill-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
}

.skill-card__icon {
  font-size: 2rem;
  margin-bottom: 1rem;
}

.skill-card__title {
  font-family: var(--font-heading);
  font-size: 1.8rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.skill-card__list {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.skill-card__list li {
  font-size: 0.9rem;
  color: var(--text-muted);
  padding-left: 1rem;
  position: relative;
  transition: color var(--transition);
}

.skill-card__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 4px;
  height: 4px;
  background: var(--gradient);
  border-radius: 50%;
}

.skill-card:hover .skill-card__list li {
  color: var(--text);
}

/* ============================================================
   EXPERIENCE TIMELINE
   ============================================================ */
.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(to bottom, var(--primary), transparent);
}

.timeline-item {
  position: relative;
  padding: 0 0 3rem 2.5rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -0.4rem;
  top: 0.4rem;
  width: 0.8rem;
  height: 0.8rem;
  background: var(--gradient);
  border-radius: 50%;
  border: 2px solid var(--bg);
}

.timeline-item__year {
  font-family: var(--font-heading);
  font-size: 1rem;
  color: var(--primary);
  letter-spacing: 0.1em;
  margin-bottom: 0.3rem;
}

.timeline-item__role {
  font-family: var(--font-heading);
  font-size: 1.8rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  line-height: 1.1;
  margin-bottom: 0.2rem;
}

.timeline-item__org {
  font-size: 0.85rem;
  color: var(--secondary);
  font-weight: 500;
  margin-bottom: 0.75rem;
}

.timeline-item__desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  max-width: 600px;
  line-height: 1.7;
}

.timeline-item__list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  max-width: 600px;
}

.timeline-item__list li {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.7;
  padding-left: 1rem;
  position: relative;
}

.timeline-item__list li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--primary);
}

/* ============================================================
   PROJECTS
   ============================================================ */
.projects__filters {
  display: flex;
  gap: 0.75rem;
  margin-bottom: 3rem;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 0.5rem 1.25rem;
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: 2rem;
  cursor: pointer;
  transition: var(--transition);
}

.filter-btn:hover,
.filter-btn.active {
  background: var(--gradient);
  color: #fff;
  border-color: transparent;
}

.projects__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition);
  cursor: pointer;
}

.project-card:hover {
  transform: translateY(-6px);
  border-color: var(--primary);
}

.project-card.hidden {
  display: none;
}

.project-card__image {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
}

.project-card__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.project-card:hover .project-card__image img {
  transform: scale(1.05);
}

.project-card__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
  opacity: 0;
  transition: opacity var(--transition);
  display: flex;
  align-items: flex-end;
  padding: 1rem;
}

.project-card:hover .project-card__overlay {
  opacity: 1;
}

.project-card__body {
  padding: 1.25rem;
}

.project-card__category {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 0.4rem;
}

.project-card__title {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.project-card__desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 0.75rem;
}

.project-card__link {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  transition: opacity var(--transition);
}

.project-card__link:hover {
  opacity: 0.7;
}

/* ============================================================
   CONTACT
   ============================================================ */
.contact__content {
  max-width: 600px;
}

.contact__intro {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  line-height: 1.7;
}

.contact__links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), transform var(--transition);
  color: var(--text);
}

.contact-link:hover {
  border-color: var(--primary);
  transform: translateX(6px);
}

.contact-link__icon {
  width: 2rem;
  height: 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  transition: color var(--transition);
  flex-shrink: 0;
}

.contact-link:hover .contact-link__icon {
  color: var(--primary);
}

.contact-link__label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  display: block;
  margin-bottom: 0.1rem;
}

.contact-link__value {
  font-size: 0.95rem;
  font-weight: 500;
}

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  background: var(--bg-dark);
  border-top: 1px solid var(--border);
  padding: 2rem 0;
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer__logo {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer__copy {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* ============================================================
   BACK TO TOP BUTTON
   ============================================================ */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 3rem;
  height: 3rem;
  background: var(--gradient);
  color: white;
  border: none;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition);
  z-index: 90;
  box-shadow: 0 4px 12px rgba(255, 59, 48, 0.3);
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 16px rgba(255, 59, 48, 0.4);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 768px) {
  .nav__links {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(10, 10, 10, 0.98);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2.5rem;
    z-index: 150;
    overflow-y: auto;
  }

  .nav__links.open {
    display: flex;
  }

  .nav__link {
    font-size: 1rem;
  }

  .nav__toggle {
    display: flex;
    z-index: 200;
  }

  .nav__toggle.open span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .nav__toggle.open span:nth-child(2) {
    opacity: 0;
  }

  .nav__toggle.open span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .about__grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .about__image {
    order: -1;
  }

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

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

  .section {
    padding: 5rem 0;
  }

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

@media (max-width: 480px) {
  .container {
    padding: 0 1.25rem;
  }

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

/* ============================================================
   PROJECT MODAL
   ============================================================ */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 200;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.modal.open {
  display: flex;
}

.modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(6px);
  cursor: pointer;
}

.modal__container {
  position: relative;
  z-index: 1;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 100%;
  max-width: 900px;
  max-height: 90vh;
  overflow-y: auto;
  padding: 2.5rem;
  animation: modalIn 0.3s ease;
}

@keyframes modalIn {
  from { opacity: 0; transform: translateY(20px) scale(0.97); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}

.modal__close {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 1.4rem;
  line-height: 1;
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.modal__close:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.modal__header {
  margin-bottom: 2rem;
}

.modal__category {
  display: block;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 0.4rem;
}

.modal__title {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  line-height: 1;
  margin-bottom: 0.75rem;
}

.modal__desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 1rem;
}

.modal__links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 0.5rem;
}

.modal__link {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  border-bottom: 1px solid var(--primary);
  padding-bottom: 1px;
  transition: opacity var(--transition);
}

.modal__link:hover {
  opacity: 0.7;
}

.modal__gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1rem;
}

.modal__gallery img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  cursor: zoom-in;
  transition: transform var(--transition), border-color var(--transition);
}

.modal__gallery img:hover {
  transform: scale(1.02);
  border-color: var(--primary);
}

.modal__empty {
  color: var(--text-dim);
  font-size: 0.9rem;
  font-style: italic;
}

@media (max-width: 600px) {
  .modal__container {
    padding: 1.5rem;
  }

  .modal__gallery {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  }
}

/* ============================================================
   TOOLS SECTION
   ============================================================ */
.tools__grid {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.tools__group-label {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.tools__group-label:first-child {
  margin-top: 0;
}

.tools__row {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.tool-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1rem;
  width: 130px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  text-align: center;
  text-decoration: none;
  color: var(--text);
  transition: border-color var(--transition), transform var(--transition);
  cursor: pointer;
}

.tool-item:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
}

.tool-item__icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition);
}

.tool-item:hover .tool-item__icon {
  transform: scale(1.15);
}

.tool-item__icon svg,
.tool-item__icon img {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.tool-item__name {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text);
}

.tool-item__category {
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-dim);
}

/* ============================================================
   CERTIFICATES SECTION
   ============================================================ */
.certificates__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.cert-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: border-color var(--transition), transform var(--transition);
}

.cert-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
}

.cert-card__year {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.cert-card__title {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  margin-bottom: 0.3rem;
}

.cert-card__issuer {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.cert-card__link {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.empty-state {
  color: var(--text-dim);
  font-style: italic;
  font-size: 0.9rem;
}

/* ============================================================
   LIGHTBOX
   ============================================================ */
.lightbox {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 300;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.lightbox.open {
  display: flex;
}

.lightbox__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.95);
  cursor: pointer;
}

.lightbox__close {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  z-index: 1;
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 1.4rem;
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.lightbox__close:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.lightbox__img {
  position: relative;
  z-index: 1;
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius);
  animation: modalIn 0.25s ease;
}

/* ============================================================
   MOBILE IMPROVEMENTS
   ============================================================ */
@media (max-width: 768px) {
  .tools__grid {
    grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
  }

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

  .timeline {
    padding-left: 1.25rem;
  }

  .timeline-item {
    padding-left: 1.75rem;
  }

  .hero__bg-text {
    font-size: clamp(5rem, 25vw, 10rem);
  }

  .section__title {
    font-size: clamp(2rem, 8vw, 3rem);
  }

  .contact__links {
    gap: 0.75rem;
  }
}

@media (max-width: 480px) {
  .tools__grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .projects__filters {
    gap: 0.5rem;
  }

  .filter-btn {
    padding: 0.4rem 0.9rem;
    font-size: 0.72rem;
  }
}