/* ============================================================
   style.css — Juan Flores personal website
   Strict minimalism: CSS custom properties, dark mode,
   responsive, single-column narrative flow.
   ============================================================ */

/* ── 1. Custom Properties (Design Tokens) ───────────────── */
:root {
  /* Colors — light mode */
  --color-bg:         #fafafa;
  --color-surface:    #ffffff;
  --color-border:     #e8e8e8;
  --color-text:       #111111;
  --color-text-muted: #6b6b6b;
  --color-accent:     #2563eb;        /* muted blue */
  --color-accent-hover: #1d4ed8;
  --color-tag-bg:     #eef2ff;
  --color-tag-text:   #3730a3;
  --color-badge-bg:   #dcfce7;
  --color-badge-text: #166534;
  --color-timeline-line: #e8e8e8;

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont,
               'Segoe UI', Helvetica, Arial, sans-serif;
  --font-size-base: 1rem;       /* 16px */
  --line-height: 1.7;

  /* Spacing scale */
  --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;

  /* Layout */
  --max-width: 840px;
  --nav-height: 64px;

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  /* Shadows */
  --shadow-sm:  0 1px 3px rgba(0,0,0,.07), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md:  0 4px 12px rgba(0,0,0,.08), 0 2px 4px rgba(0,0,0,.04);

  /* Transitions */
  --transition: 200ms ease;
}

/* Dark mode tokens */
html.dark {
  --color-bg:         #0f0f0f;
  --color-surface:    #1a1a1a;
  --color-border:     #2a2a2a;
  --color-text:       #f0f0f0;
  --color-text-muted: #888888;
  --color-accent:     #60a5fa;
  --color-accent-hover: #93c5fd;
  --color-tag-bg:     #1e2a4a;
  --color-tag-text:   #93c5fd;
  --color-badge-bg:   #14532d;
  --color-badge-text: #86efac;
  --color-timeline-line: #2a2a2a;
  --shadow-sm:  0 1px 3px rgba(0,0,0,.3);
  --shadow-md:  0 4px 12px rgba(0,0,0,.4);
}

/* ── Skip Link ─────────────────────────────────────────── */
.skip-link {
  position: absolute;
  left: -9999px;
  top: var(--space-2);
  z-index: 200;
  padding: var(--space-2) var(--space-4);
  font-size: 0.875rem;
  font-weight: 500;
  background-color: var(--color-accent);
  color: #fff;
  border-radius: var(--radius-sm);
  text-decoration: none;
}

.skip-link:focus-visible {
  left: var(--space-4);
  color: #fff;
}

/* ── 2. Reset & Base ────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: var(--line-height);
  background-color: var(--color-bg);
  color: var(--color-text);
  transition: background-color var(--transition), color var(--transition);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition);
}

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

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

ul, ol { list-style: none; }

/* ── 3. Layout Utilities ────────────────────────────────── */
.container {
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

/* ── 4. Navigation ──────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  transition: background-color var(--transition), border-color var(--transition);
}

/* Backdrop blur via pseudo-element so it doesn't create a stacking context
   that would trap position:fixed children (the mobile menu) */
.site-header::before {
  content: '';
  position: absolute;
  inset: 0;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: -1;
  pointer-events: none;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.nav__logo {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: -0.01em;
  transition: color var(--transition);
}

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

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.nav__link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition);
  letter-spacing: 0.01em;
}

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

/* Theme toggle button */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: color var(--transition), border-color var(--transition),
              background-color var(--transition);
}

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

/* Show moon in light mode (click to go dark), sun in dark mode (click to go light) */
.icon--moon { display: block; }
.icon--sun  { display: none; }

html.dark .icon--moon { display: none; }
html.dark .icon--sun  { display: block; }

/* Font Awesome icon sizing */
.theme-toggle i[class*="fa-"] {
  font-size: 1.125rem; /* 18px — matches previous SVG size */
}

.btn i[class*="fa-"] {
  font-size: 1rem; /* 16px — matches previous SVG size */
}

/* Hamburger — hidden on desktop */
.nav__hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: var(--space-2);
  width: 44px;
  height: 44px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}

.nav__hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* Hamburger open state */
.nav__hamburger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(10px) rotate(45deg);
}
.nav__hamburger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}
.nav__hamburger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-10px) rotate(-45deg);
}

/* ── 5. Sections ────────────────────────────────────────── */
.section {
  padding-block: var(--space-20);
  border-top: 1px solid var(--color-border);
}

.section__title {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

.section__subtitle {
  font-size: 1rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-10);
}

/* ── 6. Hero Section ────────────────────────────────────── */
.hero {
  padding-block: var(--space-24) var(--space-20);
}

.hero__eyebrow {
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.hero__name {
  font-size: clamp(2.5rem, 8vw, 4rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.05;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.hero__title {
  font-size: clamp(1rem, 3vw, 1.25rem);
  font-weight: 400;
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.hero__bio {
  font-size: 1.0625rem;
  color: var(--color-text-muted);
  max-width: 600px;
  margin-bottom: var(--space-8);
}

.hero__bio strong {
  color: var(--color-text);
  font-weight: 600;
}

.hero__links {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

/* ── 7. Buttons ─────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-5);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background-color var(--transition), color var(--transition),
              border-color var(--transition), box-shadow var(--transition);
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid transparent;
}

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

.btn--outline:hover {
  background-color: var(--color-surface);
  border-color: var(--color-text-muted);
  color: var(--color-text);
  box-shadow: var(--shadow-sm);
}

.btn--ghost {
  color: var(--color-accent);
  background: transparent;
  border: none;
  padding-inline: 0;
}

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

.btn--sm {
  font-size: 0.8125rem;
  padding: var(--space-2) var(--space-3);
}

/* ── 8. Projects Grid ───────────────────────────────────── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-5);
}

/* Card */
.card {
  position: relative;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  transition: border-color var(--transition), box-shadow var(--transition),
              transform var(--transition);
}

.card__link::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
}

.card:hover {
  border-color: var(--color-text-muted);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.card__body {
  padding: var(--space-6);
  flex: 1;
}

.card__title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-3);
  letter-spacing: -0.01em;
}

.card__desc {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: var(--space-4);
}

.card__footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--color-border);
}

/* Tags */
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.tag {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: 0.75rem;
  font-weight: 500;
  background-color: var(--color-tag-bg);
  color: var(--color-tag-text);
  border-radius: 999px;
  letter-spacing: 0.01em;
}

/* ── 9. Timeline ────────────────────────────────────────── */
.timeline {
  position: relative;
  padding-left: var(--space-6);
}

/* Vertical line */
.timeline::before {
  content: '';
  position: absolute;
  left: calc(var(--space-6) - 1px);
  top: var(--space-3);
  bottom: var(--space-3);
  width: 1px;
  background-color: var(--color-timeline-line);
  transform: translateX(-50%);
}

.timeline__item {
  position: relative;
  padding-left: var(--space-8);
  padding-bottom: var(--space-10);
}

.timeline__item:last-child {
  padding-bottom: 0;
}

/* Dot marker */
.timeline__marker {
  position: absolute;
  left: 0;
  top: var(--space-3);
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--color-accent);
  border: 2px solid var(--color-bg);
  box-shadow: 0 0 0 2px var(--color-accent);
  transform: translateX(-50%);
  transition: background-color var(--transition), box-shadow var(--transition);
}

.timeline__item:not(:first-child) .timeline__marker {
  background-color: var(--color-border);
  box-shadow: 0 0 0 2px var(--color-border);
}

.timeline__header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-1);
}

.timeline__role {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.timeline__badge {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  background-color: var(--color-badge-bg);
  color: var(--color-badge-text);
  border-radius: 999px;
}

.timeline__company {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-muted);
  margin-bottom: var(--space-1);
}

.timeline__period {
  display: block;
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}

.timeline__desc {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  line-height: 1.65;
  max-width: 560px;
}

/* ── 10. Certifications ─────────────────────────────────── */
.certs-grid {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: var(--space-12);
  align-items: start;
}

.certs__subtitle {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-5);
}

/* Cert list */
.certs-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.cert-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-4);
  padding-block: var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.cert-item:first-child {
  border-top: 1px solid var(--color-border);
}

.cert-item__info {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 0;
}

.cert-item__name {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text);
  line-height: 1.4;
}

.cert-item__issuer {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

.cert-item__date {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  white-space: nowrap;
  flex-shrink: 0;
}

/* Language list */
.lang-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.lang-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding-block: var(--space-3);
  border-bottom: 1px solid var(--color-border);
}

.lang-item:first-child {
  border-top: 1px solid var(--color-border);
}

.lang-item__name {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text);
}

.lang-item__level {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

/* ── 11. Footer ─────────────────────────────────────────── */
.site-footer {
  margin-top: var(--space-16);
  padding-block: var(--space-8);
  border-top: 1px solid var(--color-border);
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.footer__copy {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.footer__links {
  display: flex;
  gap: var(--space-12);
}

.footer__link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition);
}

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

/* ── 12. Project Page ───────────────────────────────────── */
.project__back {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
  transition: color var(--transition);
}

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

.project__back i {
  font-size: 0.875rem;
}

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

.hero__tags {
  margin: 0;
}

.project__prose {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  max-width: 640px;
  font-size: 1.0625rem;
  color: var(--color-text-muted);
  line-height: var(--line-height);
}

.project__prose strong {
  color: var(--color-text);
  font-weight: 600;
}

.project__features {
  display: flex;
  flex-direction: column;
  gap: 0;
  max-width: 640px;
}

.project__feature {
  display: flex;
  gap: var(--space-5);
  align-items: flex-start;
  padding-block: var(--space-5);
  border-bottom: 1px solid var(--color-border);
}

.project__feature:first-child {
  border-top: 1px solid var(--color-border);
}

.project__feature-icon {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-tag-bg);
  color: var(--color-accent);
  border-radius: var(--radius-md);
  font-size: 1rem;
  margin-top: 2px;
}

.project__feature strong {
  display: block;
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-1);
  letter-spacing: -0.01em;
}

.project__feature p {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

.project__stack {
  max-width: 560px;
}

.project__stack-row {
  display: flex;
  gap: var(--space-6);
  padding-block: var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.project__stack-row:first-child {
  border-top: 1px solid var(--color-border);
}

.project__stack-row dt {
  flex: 0 0 120px;
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  padding-top: 2px;
}

.project__stack-row dd {
  font-size: 0.9375rem;
  color: var(--color-text);
  line-height: 1.5;
}

/* ── 13. Scroll Animations ─────────────────────────────── */
.fade-in {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger children within grids */
.projects-grid .fade-in:nth-child(2) { transition-delay: 80ms; }
.projects-grid .fade-in:nth-child(3) { transition-delay: 160ms; }
.timeline .fade-in:nth-child(2) { transition-delay: 80ms; }
.timeline .fade-in:nth-child(3) { transition-delay: 160ms; }

/* ── 14. Legal Pages ───────────────────────────────────── */
.legal-section {
  padding-block: var(--space-16);
}

.legal-back {
  margin-bottom: var(--space-10);
}

.legal-lang {
  display: inline-block;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: var(--space-1) var(--space-3);
  margin-bottom: var(--space-5);
}

.legal-title {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.legal-meta {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-10);
}

.legal-body h2,
.legal-body h3 {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
  letter-spacing: -0.01em;
}

.legal-body p,
.legal-body li {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  line-height: var(--line-height);
}

.legal-body ul {
  list-style: disc;
  padding-left: var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-top: var(--space-2);
}

.legal-body strong {
  color: var(--color-text);
  font-weight: 600;
}

.legal-divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-16) 0;
}

/* ── 15. Responsive ─────────────────────────────────────── */
@media (max-width: 720px) {
  /* Nav: show hamburger, hide links by default */
  .nav__hamburger {
    display: flex;
  }

  .nav__links {
    display: none;
    position: fixed;
    inset: var(--nav-height) 0 0 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background-color: var(--color-bg);
    padding: var(--space-6);
    border-top: 1px solid var(--color-border);
    z-index: 99;
  }

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

  .nav__links li {
    width: 100%;
    border-bottom: 1px solid var(--color-border);
  }

  .nav__link {
    display: block;
    padding-block: var(--space-4);
    font-size: 1rem;
    color: var(--color-text);
  }

  .nav__links li:last-child {
    border: none;
    padding-top: var(--space-4);
  }

  /* Hero */
  .hero {
    padding-block: var(--space-16) var(--space-12);
  }

  /* Sections */
  .section {
    padding-block: var(--space-12);
  }

  /* Projects: single column */
  .projects-grid {
    grid-template-columns: 1fr;
  }

  /* Certs: single column */
  .certs-grid {
    grid-template-columns: 1fr;
    gap: var(--space-10);
  }

  /* Timeline */
  .timeline {
    padding-left: var(--space-5);
  }

  /* Footer */
  .footer__inner {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-2);
  }
}

@media (max-width: 480px) {
  .container {
    padding-inline: var(--space-5);
  }

  .hero__name {
    font-size: 2.5rem;
  }

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

/* ── 16. Reduced Motion ────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .fade-in {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ── 17. Print ──────────────────────────────────────────── */
@media print {
  .site-header, .theme-toggle { display: none; }
  .fade-in { opacity: 1; transform: none; }
  body { background: white; color: black; }
}