:root {
  --color-bg: #edf9fe;
  --color-bg-alt: #e0f3fd;
  --color-bg-card: #ffffff;
  --color-text: #001c55;
  --color-secondary-text: #7f8daa;
  --color-highlight: #a6e1fa;
  --color-accent: #0e6ba8;
  --color-accent-dark: #0a2472;
  --color-dark: #00072d;
  --card-shadow: 0 2px 10px rgba(0, 28, 85, 0.08);
  --max-width: 1100px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
}

h1,
h2,
h3 {
  line-height: 1.25;
  margin: 0 0 0.5em;
}

p {
  margin: 0 0 1em;
}

a {
  color: var(--color-accent);
}

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-accent-dark);
  color: #fff;
  padding: 0.75rem 1rem;
  z-index: 100;
}

.skip-link:focus {
  left: 0;
}

/* Header / nav */
.site-header {
  position: sticky;
  top: 0;
  background: rgba(237, 249, 254, 0.9);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--color-highlight);
  z-index: 50;
}

.navbar {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar__brand {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-accent-dark);
  text-decoration: none;
}

.navbar__menu {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin: 0;
  padding: 0;
}

.navbar__menu a {
  text-decoration: none;
  color: var(--color-text);
  font-weight: 500;
}

.navbar__menu a:hover {
  color: var(--color-accent);
}

.navbar__resume {
  border: 1px solid var(--color-accent);
  border-radius: 6px;
  padding: 0.4rem 0.9rem;
}

.navbar__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 34px;
  height: 34px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}

.navbar__toggle span {
  display: block;
  height: 2px;
  background: var(--color-accent-dark);
  border-radius: 2px;
}

/* Hero */
.hero {
  padding: 5rem 0 4rem;
}

.hero__inner {
  max-width: 720px;
}

.hero__eyebrow {
  color: var(--color-accent);
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.hero__name {
  font-size: clamp(2.25rem, 5vw, 3.25rem);
  color: var(--color-accent-dark);
}

.hero__subtitle {
  color: var(--color-secondary-text);
  font-size: 1.1rem;
  max-width: 600px;
}

.hero__actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin: 1.5rem 0;
}

.btn {
  display: inline-block;
  text-decoration: none;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 600;
  border: 2px solid transparent;
}

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

.btn--primary:hover {
  background: var(--color-accent);
}

.btn--secondary {
  border-color: var(--color-accent-dark);
  color: var(--color-accent-dark);
}

.btn--secondary:hover {
  background: var(--color-accent-dark);
  color: #fff;
}

.btn--sm {
  padding: 0.4rem 0.9rem;
  font-size: 0.85rem;
}

.social-list {
  list-style: none;
  display: flex;
  gap: 1rem;
  padding: 0;
  margin: 1.5rem 0 0;
}

.social-list a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-bg-card);
  box-shadow: var(--card-shadow);
}

.social-list svg {
  width: 20px;
  height: 20px;
  fill: var(--color-accent-dark);
}

/* Sections */
.section {
  padding: 4rem 0;
  background: var(--color-bg);
}

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

.section__title {
  font-size: 2rem;
  color: var(--color-accent-dark);
}

.section__subtitle {
  color: var(--color-secondary-text);
  max-width: 620px;
  margin-bottom: 2.5rem;
}

/* Cards */
.card-grid {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: 1fr;
}

@media (min-width: 881px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1121px) {
  .card-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (min-width: 881px) {
  #education .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

.card {
  background: var(--color-bg-card);
  border-radius: 20px;
  border: 1px solid var(--color-accent);
  padding: 1.75rem;
  box-shadow: var(--card-shadow);
}

.card__icon {
  width: 56px;
  height: 56px;
  margin-bottom: 1rem;
}

.card__list {
  margin: 0 0 1rem;
  padding-left: 1.1rem;
  color: var(--color-secondary-text);
  font-size: 0.95rem;
}

.card__list li {
  margin-bottom: 0.4rem;
}

.card__meta {
  color: var(--color-secondary-text);
  font-weight: 600;
  margin-top: -0.5rem;
}

#skills .card {
  display: flex;
  flex-direction: column;
}

#skills .tag-list {
  margin-top: auto;
  padding-top: 1rem;
}

.tag-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0;
  margin: 0;
}

.tag-list li {
  background: var(--color-highlight);
  color: var(--color-accent-dark);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
}

.tag-list+.tag-list {
  margin-top: 0.5rem;
}

.tag-list--topic li {
  background: var(--color-accent-dark);
  color: #fff;
}

.project-card__links {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
  font-weight: 600;
}

.project-card__details {
  display: inline-block;
  margin-top: 1rem;
}


.project-card {
  display: flex;
  flex-direction: column;
  border-radius: 20px;
  border-color: var(--color-accent-dark);
}

.project-card h3,
.project-card>p {
  margin-top: 0;
}

.project-card>.tag-list:first-of-type {
  margin-top: auto;
  padding-top: 1rem;
}

/* Project detail pages */
.back-link {
  display: inline-block;
  margin-bottom: 1.5rem;
  font-weight: 600;
  text-decoration: none;
}

.project-detail {
  padding-top: 3rem;
}

.project-detail__summary {
  color: var(--color-secondary-text);
  font-size: 1.1rem;
  /* max-width: 620px; */
}

.project-detail__links {
  display: flex;
  gap: 1rem;
  margin: 1.5rem 0 2.5rem;
}

.project-detail h2 {
  color: var(--color-accent-dark);
  margin-top: 2.5rem;
}

/* Experience timeline */
.timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 3px solid var(--color-highlight);
}

.timeline__item {
  position: relative;
  padding: 0 0 2rem 1.75rem;
}

.timeline__item::before {
  content: "";
  position: absolute;
  left: -9px;
  top: 4px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 3px solid var(--color-bg);
}

.timeline__header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.5rem;
  margin-bottom: 0.35rem;
}

.timeline__header h3 {
  margin: 0;
}

.timeline__meta {
  color: var(--color-secondary-text);
  font-size: 0.9rem;
}

/* Contact */
.contact__inner {
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
}

.contact .section__subtitle {
  margin-left: auto;
  margin-right: auto;
}

/* Footer */
.site-footer {
  padding: 2rem 0;
  border-top: 1px solid var(--color-highlight);
}

.site-footer__inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
  color: var(--color-secondary-text);
  font-size: 0.9rem;
}

.site-footer a {
  color: var(--color-secondary-text);
  text-decoration: none;
}

/* Pipeline diagram */
.pipeline-diagram-wrap {
  margin: 2rem 0;
  text-align: center;
}

.pipeline-diagram {
  display: block;
  width: 100%;
  height: auto;
  margin: 0 auto;
}

.pipeline-diagram-wrap figcaption {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--color-secondary-text);
}

/* Screenshot gallery */
.media-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.media-item {
  margin: 0;
  background: var(--color-bg-card);
  border: 1px solid var(--color-highlight);
  border-radius: 10px;
  overflow: hidden;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.media-item:hover,
.media-item:focus-within {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 28, 85, 0.12);
}

.media-item__trigger {
  display: block;
  width: 100%;
  padding: 0;
  border: none;
  background: none;
  cursor: pointer;
}

.media-item img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: top;
}

.media-item figcaption {
  padding: 0.65rem 0.85rem;
  font-size: 0.85rem;
  color: var(--color-secondary-text);
}

/* Lightbox */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  padding: 2rem;
  background: rgba(0, 7, 45, 0.85);
}

.lightbox[hidden] {
  display: none;
}

.lightbox__image {
  max-width: min(90vw, 1100px);
  max-height: 75vh;
  object-fit: contain;
  border-radius: 8px;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
}

.lightbox__caption {
  color: #ffffff;
  font-size: 0.95rem;
  max-width: 700px;
  text-align: center;
}

.lightbox__close,
.lightbox__nav {
  position: absolute;
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  color: #ffffff;
  font-size: 1.5rem;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.15s ease;
}

.lightbox__close:hover,
.lightbox__nav:hover,
.lightbox__close:focus-visible,
.lightbox__nav:focus-visible {
  background: var(--color-accent);
}

.lightbox__close {
  top: 1.5rem;
  right: 1.5rem;
}

.lightbox__nav--prev {
  left: 1.5rem;
  top: 50%;
  transform: translateY(-50%);
}

.lightbox__nav--next {
  right: 1.5rem;
  top: 50%;
  transform: translateY(-50%);
}

@media (max-width: 720px) {
  .lightbox {
    padding: 1rem;
  }

  .lightbox__close,
  .lightbox__nav {
    width: 36px;
    height: 36px;
    font-size: 1.25rem;
  }

  .lightbox__close {
    top: 0.75rem;
    right: 0.75rem;
  }

  .lightbox__nav--prev {
    left: 0.75rem;
  }

  .lightbox__nav--next {
    right: 0.75rem;
  }
}

/* Mobile nav */
@media (max-width: 880px) {
  .navbar__toggle {
    display: flex;
  }

  .navbar__menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    background: var(--color-bg-alt);
    padding: 1rem 1.5rem;
    gap: 1rem;
    border-bottom: 1px solid var(--color-highlight);
    display: none;
  }

  .navbar__menu.is-open {
    display: flex;
  }
}

/* Embedded Youtube Videos */
.video-embed {
  position: relative;
  aspect-ratio: 16 / 9;
  width: 100%;
  margin: 1.5rem 0;
}

.video-embed iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
  border-radius: 8px;
}
/* All-projects page */
#all-projects .section__title {
  margin-top: 0;
}

.section__actions {
  margin-top: 2.5rem;
}

@media (min-width: 1121px) {
  #all-projects .card-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

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

/* Tag filters */
.filters {
  margin-bottom: 2.5rem;
}

.filters__group {
  margin-bottom: 1.25rem;
}

.filters__legend {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-secondary-text);
  margin: 0 0 0.6rem;
}

.filters__chips {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0;
  margin: 0;
}

.filter-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  line-height: 1.6;
  padding: 0.25rem 0.75rem;
  border: 1px solid var(--color-accent);
  border-radius: 999px;
  background: var(--color-bg-card);
  color: var(--color-accent-dark);
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.filter-chip:hover {
  background: var(--color-highlight);
}

.filter-chip[aria-pressed="true"] {
  background: var(--color-accent-dark);
  border-color: var(--color-accent-dark);
  color: #fff;
}

.filter-chip__count {
  font-weight: 500;
  opacity: 0.65;
}

.filters__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--color-highlight);
}

.filters__status {
  margin: 0;
  color: var(--color-secondary-text);
  font-size: 0.9rem;
}

.filters__clear[hidden] {
  display: none;
}

.projects-empty {
  margin-top: 2rem;
  color: var(--color-secondary-text);
}