:root {
  /* Existing palette */
  --primary: #FFFFFF;
  --primary-dark: #111111;
  --accent-blue: #1017C2;
  --neutral-mid: #474A4C;
  --neutral-light: #9EA1AC;
  --alt-dark: #45494C;
  --alt-light: #D4D2D8;
  --space: 8px;
  --fs-display: clamp(2.5rem, 8vw + 1rem, 6rem);
  --fs-h1: clamp(1.75rem, 4vw + 0.5rem, 3rem);
  --fs-h2: clamp(1.25rem, 3vw + 0.5rem, 2rem);
  --fs-body: clamp(0.875rem, 2vw + 0.25rem, 1rem);

  /* Design system tokens */
  --ds-primary: #5C6AC4;
  --ds-primary-light: #EEF2FF;
  --ds-primary-dark: #3730A3;
  --ds-secondary: #7C3AED;
  --ds-background: #F9FAFB;
  --ds-surface: #FFFFFF;
  --ds-surface-alt: #F3F4F6;
  --ds-text-primary: #1F2937;
  --ds-text-secondary: #4B5563;
  --ds-text-on-primary: #FFFFFF;
  --ds-border: #E5E7EB;
  --ds-shadow-card: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --ds-shadow-card-hover: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
  --ds-radius-sm: 0.5rem;
  --ds-radius-md: 0.75rem;
  --ds-radius-lg: 1rem;
  --ds-section-padding: clamp(3rem, 8vw, 6rem);
  --ds-card-padding: 2rem;
  --ds-card-gap: 2rem;
  --ds-container-max-width: min(90rem, 90vw);
  --ds-gutter-sm: 1rem;
  --ds-gutter-lg: 2rem;
  --ds-transition-default: all 0.3s ease;
  --ds-font-family: 'Inter', sans-serif;
  --ds-h2-size: 2.25rem;
  --ds-h2-line: 2.5rem;
  --ds-h2-weight: 700;
  --ds-h3-size: 1.875rem;
  --ds-h3-line: 2.25rem;
  --ds-h3-weight: 600;
  --ds-body-lg-size: 1.125rem;
  --ds-body-lg-line: 1.75rem;
  --ds-body-lg-weight: 400;
  --ds-body-md-size: 1rem;
  --ds-body-md-line: 1.5rem;
  --ds-body-md-weight: 400;
  --ds-caption-size: 0.875rem;
  --ds-caption-line: 1.25rem;
  --ds-caption-weight: 500;
}

* {
  box-sizing: border-box;
}

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

html, body {
  margin: 0;
  padding: 0;
  scroll-behavior: smooth;
  font-family: var(--ds-font-family);
  background: var(--ds-background);
  color: var(--ds-text-primary);
  line-height: 1.6;
  height: 100%;
}

body {
  overflow-y: auto;
  scroll-snap-type: y mandatory;
}

.main-nav {
  position: fixed;
  top: calc(var(--space) * 2);
  right: calc(var(--space) * 2);
  display: flex;
  gap: calc(var(--space) * 2);
  z-index: 1000;
}

.main-nav a {
  padding: calc(var(--space)) calc(var(--space) * 2);
  border-radius: 9999px;
  border: 1px solid var(--neutral-mid);
  color: var(--primary-dark);
  text-decoration: none;
  transition: background-color 200ms ease-in-out;
}

.main-nav a:hover {
  background-color: var(--neutral-light);
}
.main-nav.white a {
  color: #fff;
  border-color: #fff;
}

.main-nav.white a:hover {
  background-color: rgba(255, 255, 255, 0.2);
}


.section {
  min-height: 100vh;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  max-width: var(--ds-container-max-width);
  margin: 0 auto;
  padding: calc(var(--space) * 4);
  align-items: center;
  scroll-snap-align: start;
  scroll-snap-stop: always;
}

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

.section.full {
  grid-template-columns: 1fr;
}
.section.full .section-content {
  max-width: none;
}

.section-content {
  max-width: 600px;
}

.display {
  font-size: var(--fs-display);
  font-weight: 700;
  line-height: 1.1;
  margin: 0 0 calc(var(--space) * 2) 0;
  transition: transform 1s ease-out;
  transform: translateX(0);
}

.hero .display {
  font-size: var(--fs-display);
}

.hero.intro .display {
  transform: translateX(-50vw);
}

.hero {
  position: relative;
  overflow: hidden;
}

.hero .display span {
  display: inline-block;
  transition: color 0.2s linear;
}

.hero .section-image img {
  transition: transform 1s ease-out;
  transform-origin: center center;
  transform: scale(1);
}

h2 {
  font-size: var(--fs-h2);
  line-height: 1.1;
  font-weight: 700;
  margin: 0 0 calc(var(--space) * 2) 0;
}

.tagline {
  font-size: var(--fs-body);
  color: var(--neutral-mid);
}

.profile-photo,
.section-image img {
  width: 100%;
  border-radius: 8px;
  display: block;
}

.skills-list,
.projects {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: calc(var(--space) * 2);
}

.skills-list li,
.project,
.case-study {
  background: var(--primary);
  border-radius: 8px;
  padding: calc(var(--space) * 2);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  text-decoration: none;
  color: inherit;
  display: block;
}

.skills-list li:hover,
.case-study:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.projects {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: calc(var(--space) * 2);
}

.contact-button {
  display: block;
  width: fit-content;
  margin-left: auto;
  padding: 1rem 2rem;
  border-radius: 8px;
  background: var(--accent-blue);
  color: var(--primary) !important;
  text-decoration: none;
  transition: transform 0.2s ease-in-out, background-color 0.2s ease-in-out;
}

.contact-button:hover {
  transform: scale(1.05);
}

.contact-button.clicked {
  background: var(--alt-light);
  color: var(--primary-dark);
}
#contact a:not(.contact-button) {
  color: var(--accent-blue);
  text-decoration: none;
}

#contact a:not(.contact-button):hover {
  text-decoration: underline;
}

.hidden {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

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

#about.slide-right {
  animation: slideRight 0.6s forwards;
}

#about.slide-left {
  animation: slideLeft 0.6s forwards;
}

@keyframes slideRight {
  from { opacity: 0; transform: translateX(-40px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes slideLeft {
  from { opacity: 0; transform: translateX(40px); }
  to { opacity: 1; transform: translateX(0); }
}

@media (max-width: 900px) {
  .section {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .section-image {
    order: -1;
  }

  .main-nav {
    position: static;
    justify-content: center;
    margin: calc(var(--space) * 2) 0;
  }
}

@media (max-width: 600px) {
  .main-nav {
    flex-wrap: wrap;
    gap: var(--ds-gutter-sm);
  }

  .main-nav a {
    padding: calc(var(--space) / 2) var(--space);
    font-size: 0.875rem;
  }

  .section {
    padding: calc(var(--space) * 2);
    gap: var(--space);
  }

  .portfolio-carousel .project-card {
    flex-basis: 100%;
  }
}

/* Design system layouts */
.ds-section {
  padding-block: var(--ds-section-padding);
  display: block;
  grid-template-columns: none;
  min-height: 100vh;
  max-width: none;
  margin: 0;
}

.ds-section .container {
  max-width: var(--ds-container-max-width);
  margin-inline: auto;
  padding-inline: var(--ds-gutter-lg);
}

.ds-section .section-header {
  text-align: center;
  margin-bottom: var(--ds-card-gap);
}

.ds-section .section-header h2,
.ds-section .section-header h3 {
  margin: 0 0 1rem 0;
}

.ds-section h2 {
  font-size: var(--ds-h2-size);
  line-height: var(--ds-h2-line);
  font-weight: var(--ds-h2-weight);
  color: var(--ds-text-primary);
}

.ds-section h3 {
  font-size: var(--ds-h3-size);
  line-height: var(--ds-h3-line);
  font-weight: var(--ds-h3-weight);
  color: var(--ds-text-primary);
}

.ds-section .section-header .subtitle {
  margin: 0 auto;
  max-width: 48rem;
  color: var(--ds-text-secondary);
  font-size: var(--ds-body-lg-size);
  line-height: var(--ds-body-lg-line);
}

/* Section backgrounds */
.expertise-section {
  background: var(--ds-surface);
}

.portfolio-section {
  background: var(--ds-surface-alt);
}

.interests-section {
  display: grid;
  place-items: center;
  background: #23153c;
  color: var(--ds-text-on-primary);
  text-align: center;
  grid-template-columns: 1fr;
  justify-items: center;
  padding-block: 0;
}

.interests-section .container {
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  max-width: var(--ds-container-max-width);
  margin-inline: auto;
}

/* Expertise grid */
.expertise-grid {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: var(--ds-card-gap);
  grid-auto-rows: 1fr;
}

@media (min-width: 768px) {
  .expertise-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

.skill-card {
  background: var(--ds-surface);
  padding: var(--ds-card-padding);
  border-radius: var(--ds-radius-md);
  box-shadow: var(--ds-shadow-card);
  text-align: center;
  display: flex;
  flex-direction: column;
  height: 100%;
  transition: var(--ds-transition-default);
}

.skill-card:hover {
  box-shadow: var(--ds-shadow-card-hover);
}

.icon-wrapper {
  width: 4rem;
  height: 4rem;
  border-radius: 50%;
  background: var(--ds-primary-light);
  color: var(--ds-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-inline: auto;
  margin-bottom: 1.5rem;
  font-size: 1.5rem;
}

.skill-card h3 {
  font-size: var(--ds-h3-size);
  line-height: var(--ds-h3-line);
  font-weight: var(--ds-h3-weight);
  color: var(--ds-text-primary);
  margin-bottom: 0.75rem;
}

.skill-card p {
  font-size: var(--ds-body-md-size);
  line-height: var(--ds-body-md-line);
  color: var(--ds-text-secondary);
  margin: 0;
}

/* Portfolio carousel */
.portfolio-carousel {
  display: flex;
  gap: var(--ds-card-gap);
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}

.portfolio-carousel::-webkit-scrollbar {
  display: none;
}

.portfolio-carousel .project-card {
  flex: 0 0 80%;
  scroll-snap-align: center;
}

@media (min-width: 768px) {
  .portfolio-carousel .project-card {
    flex-basis: 45%;
  }
}

@media (min-width: 1024px) {
  .portfolio-carousel .project-card {
    flex-basis: 30%;
  }
}

.project-card {
  background: var(--ds-surface);
  border-radius: var(--ds-radius-lg);
  box-shadow: var(--ds-shadow-card);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--ds-transition-default);
}

.project-card:hover {
  box-shadow: var(--ds-shadow-card-hover);
}

.project-card.active {
  transform: scale(1.05);
}

.project-card img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
  display: block;
}

.project-card .content {
  padding: var(--ds-card-padding);
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.project-card h3 {
  font-size: var(--ds-h3-size);
  line-height: var(--ds-h3-line);
  font-weight: var(--ds-h3-weight);
  color: var(--ds-text-primary);
  margin: 0 0 0.75rem 0;
}

.project-card p {
  font-size: var(--ds-body-md-size);
  line-height: var(--ds-body-md-line);
  color: var(--ds-text-secondary);
  flex-grow: 1;
  margin: 0 0 1rem 0;
}

.project-card a {
  font-size: var(--ds-caption-size);
  line-height: var(--ds-caption-line);
  font-weight: var(--ds-caption-weight);
  color: var(--ds-primary);
  text-decoration: none;
  transition: var(--ds-transition-default);
}

.project-card a:hover {
  color: var(--ds-primary-dark);
}

/* Interests */
.interests-section .section-header h3 {
  font-size: var(--ds-h3-size);
  line-height: var(--ds-h3-line);
  font-weight: var(--ds-h3-weight);
  color: inherit;
}

.interests-section .section-header p {
  font-size: var(--ds-body-md-size);
  line-height: var(--ds-body-md-line);
  color: rgba(255, 255, 255, 0.85);
  max-width: 40rem;
  margin-inline: auto;
}

/* Contact form */
.contact-section {
  position: relative;
  overflow: hidden;
  color: var(--ds-text-on-primary);
}

.contact-section .container {
  max-width: var(--ds-container-max-width);
  margin-inline: auto;
}

.contact-section .section-header h2 {
  font-size: var(--ds-h2-size);
  line-height: var(--ds-h2-line);
  font-weight: var(--ds-h2-weight);
  color: var(--ds-text-on-primary);
}

.contact-section .section-header .subtitle {
  color: rgba(255,255,255,0.7);
  max-width: 40rem;
}

.contact-form {
  background: var(--ds-surface);
  color: var(--ds-text-primary);
  padding: 2rem;
  border-radius: var(--ds-radius-lg);
  box-shadow: var(--ds-shadow-card);
  width: 100%;
  max-width: 40rem;
  margin-inline: auto;
}

.contact-form label {
  display: block;
  font-size: var(--ds-caption-size);
  line-height: var(--ds-caption-line);
  font-weight: var(--ds-caption-weight);
  color: var(--ds-text-primary);
  margin-bottom: 0.5rem;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--ds-border);
  border-radius: var(--ds-radius-sm);
  font-family: inherit;
  font-size: var(--ds-body-md-size);
  line-height: var(--ds-body-md-line);
  color: var(--ds-text-primary);
  margin-bottom: 1rem;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--ds-primary);
  box-shadow: 0 0 0 3px rgba(92,106,196,0.3);
}

.contact-form textarea {
  min-height: 150px;
  resize: vertical;
}

.contact-form button {
  background: var(--ds-primary);
  color: var(--ds-text-on-primary);
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--ds-radius-md);
  box-shadow: var(--ds-shadow-card);
  cursor: pointer;
  transition: var(--ds-transition-default);
}

.contact-form button:hover {
  background: var(--ds-primary-light);
}

.social-links {
  display: flex;
  gap: 1.5rem;
  margin-top: 1rem;
  justify-content: center;
}

.social-links a {
  color: rgba(255,255,255,0.7);
  font-size: 2rem;
  transition: var(--ds-transition-default);
}

.social-links a:hover {
  color: var(--ds-primary-light);
}

/* Visually hidden text for accessibility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}