@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Serif:ital,wght@0,400;0,500;1,400&family=IBM+Plex+Sans:wght@400;500&family=IBM+Plex+Mono:wght@400&display=swap');

/* ---- Tokens ---- */
:root {
  --font-serif: 'IBM Plex Serif', Georgia, serif;
  --font-sans: 'IBM Plex Sans', -apple-system, sans-serif;
  --font-mono: 'IBM Plex Mono', monospace;

  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
  --space-2xl: 6rem;

  --max-width: 720px;
  --nav-height: 60px;

  --transition: 0.2s ease;
}

/* ---- Light theme (default) ---- */
:root,
[data-theme="light"] {
  --bg-primary: #ffffff;
  --bg-secondary: #f7f7f5;
  --bg-tertiary: #efeeeb;
  --text-primary: #111111;
  --text-secondary: #4d4d4d;
  --text-tertiary: #595959;
  --border: rgba(0, 0, 0, 0.12);
  --border-hover: rgba(0, 0, 0, 0.25);
  --accent: #00734D;
  --accent-vivid: #00D88E;
  --accent-bg: #EDFFF7;
}

/* ---- Dark theme ---- */
[data-theme="dark"] {
  --bg-primary: #111110;
  --bg-secondary: #1a1a18;
  --bg-tertiary: #232321;
  --text-primary: #eeece6;
  --text-secondary: #a3a19a;
  --text-tertiary: #8a8882;
  --border: rgba(255, 255, 255, 0.1);
  --border-hover: rgba(255, 255, 255, 0.2);
  --accent: #00F0A0;
  --accent-vivid: #00F0A0;
  --accent-bg: rgba(0, 240, 160, 0.06);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
  transition: background var(--transition), color var(--transition);
  -webkit-font-smoothing: antialiased;
}

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

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

/* ---- Layout ---- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.container--wide {
  max-width: 960px;
}

/* ---- Nav ---- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  justify-content: flex-start;
  padding: 0 var(--space-md);
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), border-color var(--transition);
}

.nav__name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  text-transform: lowercase;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-left: auto;
}

.nav__link {
  font-size: 14px;
  color: var(--text-secondary);
  transition: color var(--transition);
  text-transform: lowercase;
}

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

.nav__link--active {
  color: var(--text-primary);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.nav__controls {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-left: var(--space-md);
  padding-left: var(--space-md);
  border-left: 1px solid var(--border);
}

.nav__icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 6px;
  background: transparent;
  color: var(--text-secondary);
  font-size: 14px;
  font-family: var(--font-sans);
  font-weight: 500;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
  text-transform: lowercase;
}

.nav__icon-btn:hover {
  background: var(--bg-secondary);
  color: var(--text-primary);
}

.nav__icon-btn svg {
  width: 16px;
  height: 16px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ---- Hero ---- */
.hero {
  background: var(--accent-bg);
  padding-top: var(--space-2xl);
  padding-bottom: var(--space-2xl);
}

.hero__inner {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.hero__image {
  flex-shrink: 0;
}

.hero__avatar {
  width: 156px;
  height: 156px;
  border-radius: 50%;
  display: block;
}

@keyframes spin-cw {
  from { transform: rotate(0deg) scale(1); }
  to   { transform: rotate(360deg) scale(1.1); }
}

@keyframes spin-ccw {
  from { transform: rotate(0deg) scale(1.1); }
  to   { transform: rotate(-360deg) scale(1); }
}

.hero__avatar.spin-cw {
  animation: spin-cw 0.7s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.hero__avatar.spin-ccw {
  animation: spin-ccw 0.7s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.hero__text {
  flex: 1;
}

.hero__headline {
  font-family: var(--font-serif);
  font-size: clamp(24px, 4vw, 34px);
  font-weight: 400;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: var(--space-sm);
}

.hero__sub {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: var(--space-md);
}

.hero__actions {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.hero__btn {
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 500;
  padding: 8px 18px;
  border-radius: 6px;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
  text-decoration: none;
}

.hero__btn--primary {
  background: #45AB9C;
  color: #fff;
  border: 1px solid #45AB9C;
}

.hero__btn--primary:hover {
  background: #3a9688;
  border-color: #3a9688;
}

.hero__btn--secondary {
  background: transparent;
  color: #45AB9C;
  border: 1px solid #45AB9C;
}

.hero__btn--secondary:hover {
  background: #45AB9C;
  color: #fff;
}

/* ---- Project list ---- */
.projects {
  margin-top: 10px;
  margin-bottom: 10px;
}

.project {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: 2rem var(--space-sm);
  border-bottom: 1px solid var(--border);
  border: 1px solid transparent;
  border-radius: 6px;
  transition: border-color var(--transition);
  cursor: pointer;
}

.project:hover {
  background: #fafafa;
}

.project:hover .project__title {
  color: #45AB9C;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.project__number {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.03em;
  font-variant-numeric: tabular-nums;
  color: #45AB9C;
  min-width: 24px;
}

.project__content {
  flex: 1;
}

.project__title {
  font-size: 16px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
  transition: color var(--transition);
}

.project__outcome {
  font-size: 14px;
  color: var(--text-secondary);
}

.project__tag {
  font-size: 14px;
  letter-spacing: 0.03em;
  color: var(--text-tertiary);
  padding: 3px 10px;
  border: 1px solid var(--border);
  border-radius: 100px;
  white-space: nowrap;
  align-self: center;
}

.project__arrow {
  font-size: 14px;
  color: var(--text-tertiary);
  align-self: center;
}

.project:last-child {
  border-bottom: none;
}

/* ---- About page ---- */
.about-intro {
  padding: var(--space-2xl) 0 var(--space-xl);
}

.about-intro__headline {
  font-family: var(--font-serif);
  font-size: clamp(24px, 3.5vw, 32px);
  font-weight: 400;
  line-height: 1.35;
  color: var(--text-primary);
  margin-bottom: var(--space-md);
}

.about-intro__text {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 560px;
}

.about-intro__text + .about-intro__text {
  margin-top: var(--space-sm);
}

.about-photo {
  width: 96px;
  height: 96px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center 20%;
  margin-bottom: var(--space-lg);
}

.about-personal {
  font-style: italic;
  margin-top: var(--space-md);
}

.section {
  padding: 30px 0 var(--space-xl);
  border-top: 1px solid var(--border);
}

.section__label {
  font-size: 14px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: 30px;
}

.principles {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.principle__title {
  font-size: 15px;
  font-weight: 500;
  color: #45AB9C;
  margin-bottom: 6px;
}

.principle__text {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 520px;
}

.timeline {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.timeline__item {
  display: flex;
  gap: var(--space-md);
}

.timeline__year {
  font-size: 14px;
  color: var(--text-tertiary);
  min-width: 80px;
  font-variant-numeric: tabular-nums;
}

.timeline__role {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
}

.timeline__company {
  font-size: 14px;
  color: var(--text-secondary);
}

/* ---- Case study ---- */
.case-hero {
  padding: var(--space-lg) 0 var(--space-xl);
}

.case-hero__back {
  font-size: 14px;
  color: var(--text-tertiary);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-bottom: var(--space-md);
  transition: color var(--transition);
}

.case-hero__back:hover {
  color: var(--text-secondary);
}

.case-year {
  display: block;
  font-size: 14px;
  color: var(--text-tertiary);
  margin-bottom: var(--space-xs);
}

.case-hero__title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 3.5vw, 32px);
  font-weight: 400;
  line-height: 1.35;
  color: var(--text-primary);
  margin-bottom: 0;
}

.case-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-lg);
  padding-bottom: var(--space-xl);
}

.case-meta__item {
  min-width: 120px;
}

.case-meta__label {
  font-size: 14px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: 4px;
}

.case-meta__value {
  font-size: 14px;
  color: var(--text-primary);
  font-weight: 500;
}

.case-section {
  padding: var(--space-xl) 0;
  border-bottom: 1px solid var(--border);
}

.case-section__label {
  font-size: 14px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: var(--space-md);
}

.case-section__text {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.case-section__text + .case-section__text {
  margin-top: var(--space-sm);
}

.case-section__list {
  list-style: none;
  padding: 0;
  margin-top: var(--space-sm);
  margin-bottom: var(--space-md);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.case-section__list li {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  padding-left: 1.2em;
  position: relative;
}

.case-section__list li::before {
  content: '—';
  position: absolute;
  left: 0;
  color: #45AB9C;
}

.case-image-placeholder {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--bg-secondary);
  border: 1px dashed var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  font-size: 14px;
  margin-top: var(--space-md);
}

/* ---- Footer ---- */
.footer {
  padding: 40px 0 var(--space-lg);
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
}

.footer__email {
  font-size: 14px;
  color: var(--text-primary);
  font-weight: 500;
}

.footer__tagline {
  font-size: 14px;
  color: #1a5c52;
  margin-bottom: 3px;
}

.footer__links {
  display: flex;
  gap: var(--space-md);
}

.footer__link {
  font-size: 14px;
  color: var(--text-secondary);
  transition: color var(--transition);
}

.footer__link:hover {
  color: var(--text-primary);
}

/* ---- Hamburger (hidden on desktop) ---- */
.nav__hamburger {
  display: none;
}

/* ---- Responsive ---- */
@media (max-width: 600px) {
  /* Nav: row 1 = name + hamburger + controls, row 2 = links (when open) */
  .nav {
    height: auto;
    flex-wrap: wrap;
    align-items: center;
    padding-top: 24px;
    padding-bottom: 24px;
    gap: 8px;
  }

  .nav__name {
    flex: 1;
    font-size: 16px;
    font-weight: 600;
  }

  .nav__hamburger {
    display: flex;
    align-items: center;
    justify-content: center;
    order: 1;
    width: 32px;
    height: 32px;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0;
    margin-left: -12px;
  }

  .nav__name {
    order: 2;
    flex: 1;
    font-size: 16px;
    font-weight: 600;
  }

  .nav__controls {
    order: 3;
    margin-left: 0;
    margin-right: -12px;
    padding-left: 0;
    border-left: none;
  }

  .nav__links {
    display: none;
    order: 5;
    width: 100%;
    flex-direction: column;
    margin-left: 0;
    margin-top: 8px;
    gap: var(--space-sm);
    padding-top: var(--space-sm);
    padding-left: 12px;
    border-top: 1px solid var(--border);
  }

  .nav--open .nav__links {
    display: flex;
  }

  .nav__link {
    font-size: 14px;
  }

  .project__tag {
    display: none;
  }

  /* Spacing */
  .hero {
    padding: var(--space-xl) 0 var(--space-lg);
  }

  .hero__inner {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-md);
  }

  .about-intro {
    padding: var(--space-xl) 0 var(--space-lg);
  }

  .section {
    padding: var(--space-lg) 0;
  }

  .case-hero {
    padding: var(--space-md) 0 var(--space-lg);
  }

  .case-section {
    padding: var(--space-lg) 0;
  }

  /* Projects */
  .project {
    flex-wrap: wrap;
    gap: var(--space-xs);
  }

  .project__tag {
    margin-left: 24px;
  }

  /* Case meta */
  .case-meta {
    gap: var(--space-md);
  }

  /* Diagram: hide inline arrows when stages wrap */
  .case-diagram__arrow {
    display: none;
  }

  /* Footer */
  .footer {
    flex-direction: column;
    gap: var(--space-sm);
  }

  /* Timeline */
  .timeline__item {
    flex-direction: column;
    gap: 2px;
  }

  .timeline__year {
    min-width: unset;
  }
}

/* ---- Utilities ---- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
}

/* ---- Case study: TL;DR ---- */
.case-tldr {
  background: var(--accent-bg);
  margin: 0 calc(-1 * var(--space-md));
  padding: var(--space-lg) var(--space-md);
  border-radius: 0;
  border-bottom: none;
  border-left: 3px solid var(--accent-vivid);
}

.case-tldr .case-section__label {
  color: var(--accent);
}

.case-header {
  background: var(--accent-bg);
}

.case-summary {
  border: 1px solid #45AB9C;
  border-radius: 6px;
  padding: 24px;
  margin-top: var(--space-lg);
  margin-bottom: 0;
  margin-left: -24px;
  margin-right: -24px;
}

.case-summary .case-section__label {
  color: #45AB9C;
}

.case-summary .case-section__text {
  font-size: 15px;
  color: var(--text-primary);
  line-height: 1.7;
  max-width: 100%;
}

/* ---- Case study: skills grid ---- */
.case-skills-grid {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: var(--space-md);
}

.case-skill {
  display: flex;
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--border);
}

.case-skill:first-child {
  padding-top: 0;
}

.case-skill__number {
  font-size: 14px;
  letter-spacing: 0.05em;
  color: var(--accent);
  min-width: 24px;
  flex-shrink: 0;
  padding-top: 3px;
  font-variant-numeric: tabular-nums;
}

.case-skill__body {
  flex: 1;
  min-width: 0;
}

.case-skill__title {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.case-skill__text {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Cross-cutting skill */
.case-skill--cross {
  display: flex;
  gap: var(--space-md);
  padding: var(--space-md);
  margin-top: var(--space-lg);
  background: var(--accent-bg);
  border-radius: 8px;
  border: 1px dashed var(--accent-vivid);
}

.case-skill--cross__marker {
  font-size: 14px;
  color: var(--accent-vivid);
  min-width: 24px;
  flex-shrink: 0;
  padding-top: 3px;
}

/* Inline links */
.case-link {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-underline-offset: 3px;
  transition: opacity var(--transition);
}

.case-link:hover {
  opacity: 0.7;
}

/* Process diagram */
.case-diagram {
  margin-top: var(--space-lg);
  padding: var(--space-lg) var(--space-md);
  background: var(--bg-secondary);
  border-radius: 8px;
}

.case-diagram__stages {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.case-diagram__stage {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 12px 16px;
  background: var(--accent-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  min-width: 90px;
}

.case-diagram__num {
  font-size: 14px;
  color: var(--accent);
  letter-spacing: 0.05em;
}

.case-diagram__name {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
}

.case-diagram__arrow {
  font-size: 14px;
  color: var(--text-tertiary);
}

.case-diagram__cross-cutting {
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px dashed var(--accent-vivid);
  text-align: center;
}

.case-diagram__cross-label {
  font-size: 14px;
  color: var(--text-secondary);
  font-style: italic;
}