/* ============================================================
   MonPortfolio — style.css
   Mobile-first. Dark theme. Vanilla CSS, no framework.
   ============================================================ */

/* ----------------------------------------------------------
   1. Design tokens — dark mode (default)
   ---------------------------------------------------------- */
:root {
  color-scheme: dark;

  /* Colors */
  --color-bg:         #0a0a0a;
  --color-bg-alpha:   rgba(10, 10, 10, 0.85);
  --color-surface:    #141414;
  --color-text:       #e0e0e0;
  --color-text-muted: #9a9a9a;
  --color-border:     #2a2a2a;
  --color-accent:     #64ffda;
  --color-on-accent:  #0a0a0a;

  /* Typography */
  --font-base:         'Inter', system-ui, -apple-system, sans-serif;
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-size-xs:      0.8rem;
  --font-size-sm:      0.9rem;

  /* Spacing (8px grid) */
  --space-1:  8px;
  --space-2:  16px;
  --space-3:  24px;
  --space-4:  32px;
  --space-6:  48px;
  --space-8:  64px;
  --space-12: 96px;

  /* Layout */
  --max-width:       960px;
  --max-width-prose: 600px;
  --nav-height:      64px;

  /* Depth */
  --z-header:   100;
  --z-overlay:   99;
  --blur-header: 12px;
  --shadow-card: 0 12px 32px rgba(0, 0, 0, 0.5);

  /* Transitions */
  --transition-fast:   0.2s;
  --transition-base:   0.3s ease;
  --transition-reveal: 0.6s ease-out;
}

/* ----------------------------------------------------------
   2. Light mode overrides
   ---------------------------------------------------------- */
[data-theme="light"] {
  color-scheme: light;

  --color-bg:         #ffffff;
  --color-bg-alpha:   rgba(255, 255, 255, 0.9);
  --color-surface:    #f5f5f5;
  --color-text:       #1a1a1a;
  --color-text-muted: #666666;
  --color-border:     #e0e0e0;
  --color-accent:     #0a7a5f; /* ratio 4.95:1 sur blanc — passe AA */
  --color-on-accent:  #ffffff;
}

/* ----------------------------------------------------------
   3. Reset
   ---------------------------------------------------------- */
html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

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

ul { list-style: none; }

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

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

/* Focus visible — indicateur clavier pour tous les éléments interactifs */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

/* Skip-to-content — visible uniquement au focus clavier */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-2);
  background: var(--color-accent);
  color: var(--color-on-accent);
  padding: var(--space-1) var(--space-2);
  font-size: var(--font-size-sm);
  z-index: 200;
  text-decoration: none;
}

.skip-link:focus {
  top: var(--space-2);
  outline: 2px solid var(--color-on-accent);
  outline-offset: 2px;
}

/* ----------------------------------------------------------
   4. Base — body & typography
   ---------------------------------------------------------- */
body {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-base);
  font-weight: var(--font-weight-light);
  font-size: 1.1rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--transition-base), color var(--transition-base);
}

h1, h2, h3 {
  font-weight: var(--font-weight-light);
  letter-spacing: 0.05em;
  line-height: 1.2;
}

h1 { font-size: clamp(2rem, 6vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2rem); }
h3 { font-size: 1.25rem; }

p { color: var(--color-text-muted); }

/* ----------------------------------------------------------
   5. Layout utilities
   ---------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

/* ----------------------------------------------------------
   6. Navigation
   ---------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  border-bottom: 1px solid var(--color-border);
  background-color: var(--color-bg-alpha);
  backdrop-filter: blur(var(--blur-header));
  -webkit-backdrop-filter: blur(var(--blur-header));
  transition: background-color var(--transition-base), border-color var(--transition-base);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-2);
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

.nav-logo {
  font-size: 1.1rem;
  letter-spacing: 0.1em;
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-links {
  display: flex;
  gap: var(--space-3);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.nav-links a:hover { color: var(--color-text); }

/* Theme toggle */
.nav-theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: none;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  cursor: pointer;
  font-size: 1rem;
  flex-shrink: 0;
  transition: border-color var(--transition-base), color var(--transition-base);
}

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

/* Sun shown in dark mode (click → light), moon shown in light mode */
.theme-icon--moon { display: none; }
.theme-icon--sun  { display: block; }

[data-theme="light"] .theme-icon--moon { display: block; }
[data-theme="light"] .theme-icon--sun  { display: none; }

/* Hamburger */
.nav-hamburger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 1px;
  background-color: var(--color-text);
  transition: transform var(--transition-base), opacity var(--transition-fast);
}

.nav-hamburger.is-open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-hamburger.is-open span:nth-child(2) { opacity: 0; }
.nav-hamburger.is-open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* Mobile full-screen overlay */
.nav-mobile {
  position: fixed;
  inset: 0;
  z-index: var(--z-overlay);
  background-color: var(--color-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base), background-color var(--transition-base);
}

.nav-mobile.is-open {
  opacity: 1;
  pointer-events: auto;
}

.nav-mobile__links {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-6);
}

.nav-mobile__links a {
  font-size: 2rem;
  letter-spacing: 0.1em;
  color: var(--color-text);
  transition: color var(--transition-fast);
}

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

/* ----------------------------------------------------------
   7. Sections — shared
   ---------------------------------------------------------- */
.section-hero,
.section-about,
.section-projects,
.section-contact {
  padding-block: var(--space-12);
}

.section-hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
}

.section-about,
.section-projects,
.section-contact {
  border-top: 1px solid var(--color-border);
}

.section-title {
  position: relative;
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-2);
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 2px;
  background-color: var(--color-accent);
  transition: background-color var(--transition-base);
}

.section-text { max-width: var(--max-width-prose); }

/* ----------------------------------------------------------
   8. Hero
   ---------------------------------------------------------- */
.section-hero .container { text-align: center; }

.hero-title {
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  letter-spacing: 0.08em;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  letter-spacing: 0.1em;
  margin-bottom: var(--space-3);
}

.hero-description {
  max-width: 60ch;
  margin-inline: auto;
  margin-bottom: var(--space-4);
}

/* ----------------------------------------------------------
   9. About
   ---------------------------------------------------------- */
.about__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
}

.about__photo {
  aspect-ratio: 1 / 1;
  max-width: 200px;
  border: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
  letter-spacing: 0.05em;
}

.about__text {
  color: var(--color-text-muted);
  line-height: 1.8;
}

/* ----------------------------------------------------------
   10. Buttons
   ---------------------------------------------------------- */
.btn-primary {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  border: 1px solid var(--color-border);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  letter-spacing: 0.05em;
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.btn-primary:hover { border-color: var(--color-text-muted); }

.btn-accent {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  background-color: var(--color-accent);
  border: 1px solid var(--color-accent);
  color: var(--color-on-accent);
  font-family: var(--font-base);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-light);
  letter-spacing: 0.05em;
  cursor: pointer;
  align-self: flex-start;
  transition: opacity var(--transition-fast),
              background-color var(--transition-base),
              border-color var(--transition-base),
              color var(--transition-base);
}

.btn-accent:hover { opacity: 0.85; }

/* ----------------------------------------------------------
   11. Projects grid & cards
   ---------------------------------------------------------- */
.projects-grid {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: 1fr;
}

.project-card {
  border: 1px solid var(--color-border);
  background-color: var(--color-surface);
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-base),
              box-shadow var(--transition-base),
              border-color var(--transition-base),
              background-color var(--transition-base);
}

.project-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
  border-color: var(--color-text-muted);
}

.project-card__banner {
  height: 6px;
  background-color: var(--color-accent);
  transition: background-color var(--transition-base);
}

.project-card__body {
  padding: var(--space-3);
  display: flex;
  flex-direction: column;
  flex: 1;
  gap: var(--space-2);
}

.project-card__title {
  color: var(--color-text);
  font-size: 1.1rem;
  transition: color var(--transition-base);
}

.project-card__desc {
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
  line-height: 1.6;
  transition: color var(--transition-base);
}

.project-card__date {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  margin-top: var(--space-1);
}

.project-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: auto;
  padding-top: var(--space-1);
}

.project-card__tag {
  font-size: 0.75rem;
  padding: 2px var(--space-1);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  letter-spacing: 0.03em;
  transition: color var(--transition-base), border-color var(--transition-base);
}

.project-card__link {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 2px;
  align-self: flex-start;
  transition: color var(--transition-base), border-color var(--transition-base);
}

.project-card__link:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}

.project-card__private {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
  align-self: flex-start;
}

/* ----------------------------------------------------------
   12. Contact form
   ---------------------------------------------------------- */
.contact-form {
  max-width: var(--max-width-prose);
  margin-top: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.form-label {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
}

.form-field {
  -webkit-appearance: none;
  appearance: none;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text);
  font-family: var(--font-base);
  font-size: 0.95rem;
  font-weight: var(--font-weight-light);
  padding: var(--space-1) var(--space-2);
  outline: none;
  width: 100%;
  transition: border-color var(--transition-base),
              background-color var(--transition-base),
              color var(--transition-base);
}

.form-field::placeholder {
  color: var(--color-text-muted);
  opacity: 0.6;
}

.form-field:focus { border-color: var(--color-text-muted); }
.form-field:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-color: var(--color-accent);
}

.form-field--textarea {
  resize: vertical;
  min-height: 120px;
}

/* ----------------------------------------------------------
   13. Footer
   ---------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-4);
}

.site-footer .container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-1);
}

.footer-links {
  display: flex;
  gap: var(--space-3);
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

.footer-links a:hover { color: var(--color-text); }

.footer-copy,
.footer-built {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

/* ----------------------------------------------------------
   14. Utilitaires accessibilité
   ---------------------------------------------------------- */

/* Contenu réservé aux lecteurs d'écran */
.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;
}

/* Feedback du formulaire de contact */
.form-required {
  color: #ff6b6b;
  margin-left: 2px;
}

.form-required-note {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-2);
}

.form-feedback {
  font-size: var(--font-size-sm);
}

.form-feedback:not(:empty) {
  padding: var(--space-1) var(--space-2);
  border-left: 2px solid;
}

.form-feedback--error {
  color: #ff6b6b;
  border-left-color: #ff6b6b;
}

.form-feedback--success {
  color: var(--color-accent);
  border-left-color: var(--color-accent);
}

.form-feedback--loading {
  color: var(--color-text-muted);
  border-left-color: var(--color-border);
}

.btn-accent:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ----------------------------------------------------------
   15. Scroll reveal
   ---------------------------------------------------------- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-reveal), transform var(--transition-reveal);
}

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

/* ----------------------------------------------------------
   15. Responsive — ≥ 768px (tablet)
   ---------------------------------------------------------- */
@media (min-width: 768px) {
  .nav-hamburger { display: none; }
  .nav-mobile    { display: none; }

  .about__grid {
    grid-template-columns: 240px 1fr;
    align-items: start;
  }

  .about__photo { max-width: none; }

  .projects-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ----------------------------------------------------------
   16. Responsive — ≥ 1024px (desktop)
   ---------------------------------------------------------- */
@media (min-width: 1024px) {
  .projects-grid { grid-template-columns: repeat(3, 1fr); }
}

/* ----------------------------------------------------------
   17. Responsive — < 768px (mobile only)
   ---------------------------------------------------------- */
@media (max-width: 767px) {
  .nav-links { display: none; }
}

/* ----------------------------------------------------------
   19. Réduction des animations (prefers-reduced-motion)
   ---------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; }
  .reveal,
  .reveal.is-visible { opacity: 1; transform: none; transition: none; }
}