/* ============================================
   Human-In-The-Loop — Design Tokens & Styles
   Pure monochrome. Typography-driven. Apple/Ridge.
   ============================================ */

:root {
  /* Type Scale (fluid) */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);
  --text-3xl:  clamp(2.5rem,   1rem    + 4vw,    5rem);

  /* Spacing (4px base) */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Monochrome Palette — Light (default) */
  --color-bg:         #f5f4f0;
  --color-surface:    #eeedea;
  --color-border:     #d4d1ca;
  --color-text:       #1a1a1a;
  --color-text-muted: #6b6b6b;
  --color-text-faint: #a0a0a0;
  --color-inverse-bg: #1a1a1a;
  --color-inverse-text: #f5f4f0;

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;

  /* Fonts */
  --font-body: 'Satoshi', 'Helvetica Neue', sans-serif;
  --font-display: 'Satoshi', 'Helvetica Neue', sans-serif;

  /* Transitions */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);
}

/* Dark mode */
[data-theme="dark"] {
  --color-bg:         #141414;
  --color-surface:    #1c1c1c;
  --color-border:     #2e2e2e;
  --color-text:       #e8e4de;
  --color-text-muted: #8a8578;
  --color-text-faint: #5a5957;
  --color-inverse-bg: #e8e4de;
  --color-inverse-text: #141414;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg:         #141414;
    --color-surface:    #1c1c1c;
    --color-border:     #2e2e2e;
    --color-text:       #e8e4de;
    --color-text-muted: #8a8578;
    --color-text-faint: #5a5957;
    --color-inverse-bg: #e8e4de;
    --color-inverse-text: #141414;
  }
}

/* ============================================
   Global Layout
   ============================================ */

.container {
  max-width: var(--content-default);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container--wide {
  max-width: var(--content-wide);
}

.container--narrow {
  max-width: var(--content-narrow);
}

/* ============================================
   Header
   ============================================ */

.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: oklch(from var(--color-bg) l c h / 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: var(--space-5) 0;
  transition: box-shadow 300ms ease;
}

.header--scrolled {
  box-shadow: 0 1px 0 var(--color-border);
}

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

.header__logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--text-lg);
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.header__nav {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.header__link {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  letter-spacing: 0.01em;
}

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

.theme-toggle {
  color: var(--color-text-muted);
  padding: var(--space-2);
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  color: var(--color-text);
}

/* Mobile hamburger */
.header__hamburger {
  display: none;
  color: var(--color-text);
  padding: var(--space-2);
}

@media (max-width: 640px) {
  .header__nav {
    display: none;
  }
  .header__nav--open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    padding: var(--space-6);
    gap: var(--space-6);
    border-bottom: 1px solid var(--color-border);
  }
  .header__hamburger {
    display: flex;
  }
}

/* ============================================
   Hero
   ============================================ */

.hero {
  padding: clamp(var(--space-12), 8vw, var(--space-24)) 0;
  padding-bottom: clamp(var(--space-16), 10vw, var(--space-32));
}

.hero__inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-10);
  align-items: center;
}

.hero__content {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.hero__greeting {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 300;
  color: var(--color-text);
  line-height: 1.1;
}

.hero__title {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 900;
  color: var(--color-text);
  line-height: 1.02;
  letter-spacing: -0.035em;
}

.hero__subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.6;
  max-width: 42ch;
}

.hero__cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--color-inverse-bg);
  color: var(--color-inverse-text);
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-sm);
  font-weight: 500;
  text-decoration: none;
  letter-spacing: 0.01em;
  width: fit-content;
}

.hero__cta:hover {
  opacity: 0.85;
}

.hero__cta:active {
  opacity: 0.7;
}

.hero__photo-wrapper {
  position: relative;
  overflow: hidden;
  aspect-ratio: 3 / 4;
  max-height: 520px;
  justify-self: end;
}

.hero__photo {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  filter: grayscale(15%);
}

@media (max-width: 768px) {
  .hero__inner {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  .hero__photo-wrapper {
    max-height: 400px;
    aspect-ratio: 4 / 3;
    justify-self: stretch;
  }
  .hero__title {
    font-size: var(--text-2xl);
  }
}

/* ============================================
   Section shared styles
   ============================================ */

.section {
  padding: clamp(var(--space-12), 6vw, var(--space-24)) 0;
}

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

.section__label {
  font-size: var(--text-xs);
  font-weight: 500;
  color: var(--color-text-faint);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: var(--space-8);
}

.section__divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin-bottom: var(--space-8);
}

/* ============================================
   What I Do
   ============================================ */

.services__list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.service-item {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: var(--space-6);
  padding: var(--space-6) 0;
  border-bottom: 1px solid var(--color-border);
  align-items: baseline;
}

.service-item:first-child {
  padding-top: 0;
}

.service-item:last-child {
  border-bottom: none;
}

.service-item__title {
  font-weight: 700;
  font-size: var(--text-base);
  color: var(--color-text);
}

.service-item__desc {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.6;
}

@media (max-width: 640px) {
  .service-item {
    grid-template-columns: 1fr;
    gap: var(--space-2);
  }
}

/* ============================================
   Selected Work
   ============================================ */

.work__list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.work-item {
  padding: var(--space-6) 0;
  border-bottom: 1px solid var(--color-border);
}

.work-item:first-child {
  padding-top: 0;
}

.work-item:last-child {
  border-bottom: none;
}

.work-item__header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-4);
  margin-bottom: var(--space-2);
}

.work-item__company {
  font-weight: 700;
  font-size: var(--text-base);
  color: var(--color-text);
}

.work-item__tag {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  white-space: nowrap;
}

.work-item__desc {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.6;
  max-width: 65ch;
}

/* ============================================
   About
   ============================================ */

.about__text {
  font-size: var(--text-base);
  color: var(--color-text);
  line-height: 1.7;
  max-width: 60ch;
}

.about__text + .about__text {
  margin-top: var(--space-4);
}

/* ============================================
   Contact
   ============================================ */

.contact__links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  margin-top: var(--space-4);
}

.contact__email {
  font-size: var(--text-base);
  color: var(--color-text);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: var(--color-border);
}

.contact__email:hover {
  text-decoration-color: var(--color-text);
}

.contact__linkedin {
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
}

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

/* ============================================
   Footer
   ============================================ */

.footer {
  padding: var(--space-8) 0;
  border-top: 1px solid var(--color-border);
}

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

.footer__copy {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

.footer__attribution a {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  text-decoration: none;
}

.footer__attribution a:hover {
  color: var(--color-text-muted);
}

@media (max-width: 640px) {
  .footer__inner {
    flex-direction: column;
    gap: var(--space-2);
    text-align: center;
  }
}