/* =========================
   index.css — Apple Pro style
   Antoine Letellier © 2025
   ========================= */

/* ---------- Design tokens ---------- */
:root{
  /* Surfaces */
  --bg: #0b0c0d;              /* deep space */
  --bg-elev: #0f1113;         /* elevated dark */
  --text: #f2f3f7;            /* primary text */
  --muted: #a7a8b1;           /* secondary text */
  --ink: #e5e7eb;             /* card text */
  --surface: rgba(255,255,255,.06);
  --surface-2: rgba(255,255,255,.08);
  --border: rgba(255,255,255,.16);
  --ring: rgba(125,211,252,.5);

  /* Brand */
  --brand: #7dd3fc;           /* baby blue */
  --brand-ink: #0ea5e9;       /* cyan ink */
  --accent: #34d399;          /* soft mint */

  /* Effects */
  --radius: 18px;
  --radius-sm: 12px;
  --blur: 14px;
  --shadow: 0 12px 32px rgba(0,0,0,.35);
  --shadow-soft: 0 8px 24px rgba(0,0,0,.22);

  /* Layout */
  --container: clamp(980px, 86vw, 1200px);

  /* Fluid type */
  --step--1: clamp(.9rem, .83rem + .2vw, 1.02rem);
  --step-0: clamp(1rem, .95rem + .4vw, 1.125rem);
  --step-1: clamp(1.25rem, 1.1rem + .8vw, 1.6rem);
  --step-2: clamp(1.6rem, 1.35rem + 1.4vw, 2.2rem);
  --step-3: clamp(2.2rem, 1.7rem + 2.3vw, 3rem);
  --step-4: clamp(2.8rem, 2rem + 3vw, 3.8rem);
}

@media (prefers-color-scheme: light) {
  :root{
    --bg: #f7f8fa;
    --bg-elev: #ffffff;
    --text: #0b0c0d;
    --muted: #50525a;
    --ink: #0f1113;
    --surface: rgba(0,0,0,.05);
    --surface-2: rgba(0,0,0,.06);
    --border: rgba(0,0,0,.12);
    --shadow: 0 12px 32px rgba(0,0,0,.12);
    --shadow-soft: 0 8px 24px rgba(0,0,0,.08);
  }
}

/* ---------- Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Inter, "Helvetica Neue", Arial, system-ui, sans-serif; line-height: 1.5; letter-spacing: -0.011em; background: var(--bg); color: var(--text); }
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.container { width: min(var(--container), 100%); margin-inline: auto; padding-inline: clamp(12px, 2vw, 24px); }
.muted { color: var(--muted); }
.link { color: var(--brand); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); border: 0; }

/* ---------- Glass Nav ---------- */
.nav { position: sticky; top: 0; z-index: 50; backdrop-filter: saturate(140%) blur(var(--blur)); -webkit-backdrop-filter: saturate(140%) blur(var(--blur)); background: linear-gradient(180deg, rgba(255,255,255,.08), rgba(255,255,255,0)); border-bottom: 1px solid var(--border); }
.nav-container { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: inline-flex; gap: .6rem; align-items: center; font-weight: 800; letter-spacing: -.02em; }
.brand-dot { width: 10px; height: 10px; border-radius: 999px; background: radial-gradient(65% 65% at 30% 30%, var(--brand) 0 60%, var(--brand-ink) 60% 100%); box-shadow: 0 0 16px var(--brand); }
.nav-links { display: flex; gap: 1.2rem; align-items: center; font-size: var(--step--1); }
.nav-links a { padding: 8px 10px; border-radius: 999px; transition: background .25s ease; }
.nav-links a:hover { background: var(--surface); }
.cv-btn { padding: 10px 14px; border-radius: 12px; background: var(--surface); border: 1px solid var(--border); font-weight: 600; transition: transform .25s ease, background .25s ease; }
.cv-btn:hover { transform: translateY(-2px); background: var(--surface-2); }

/* ---------- Hero ---------- */
.hero { padding: clamp(42px, 7vw, 86px) 0 clamp(16px, 4vw, 40px); }
.kicker { font-size: var(--step--1); text-transform: uppercase; letter-spacing: .16em; color: var(--muted); }
.hero h1 { font-size: var(--step-4); line-height: 1.02; letter-spacing: -.035em; margin: .2rem 0 .8rem; font-weight: 900; }
.lead { font-size: var(--step-1); color: var(--muted); max-width: 70ch; }
.cta { display: flex; gap: .8rem; margin-top: 1.2rem; }

/* Buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: .55rem; padding: 12px 16px; border-radius: 12px; font-weight: 700; font-size: var(--step--1); border: 1px solid var(--border); background: var(--surface); transition: transform .25s ease, background .25s ease; }
.btn:hover { transform: translateY(-2px); background: var(--surface-2); }
.btn.primary { background: linear-gradient(180deg, rgba(125,211,252,.2), rgba(125,211,252,.08)); border-color: rgba(125,211,252,.45); }
.btn.ghost { background: transparent; }
.btn.tiny { padding: 8px 10px; font-weight: 600; border-radius: 999px; }

/* ---------- Sections ---------- */
.section { padding: clamp(22px, 5vw, 56px) 0; }
.section-head { display: grid; gap: .3rem; margin-bottom: 14px; }
.section h2 { font-size: var(--step-2); letter-spacing: -.02em; margin: 0; }

/* ---------- Cards: Certifications ---------- */
.cards-grid { display: grid; grid-template-columns: repeat(12, 1fr); gap: clamp(14px, 1.8vw, 22px); }
.cert-card { grid-column: span 4; border-radius: var(--radius); background: linear-gradient(180deg, rgba(255,255,255,.08), rgba(255,255,255,.04)); border: 1px solid var(--border); box-shadow: var(--shadow-soft); padding: 16px; display: grid; gap: 10px; }
.cert-card h3 { margin: 0; font-size: 1.06rem; letter-spacing: -.01em; }
.cert-actions { display: flex; flex-wrap: wrap; gap: .5rem; }

/* ---------- Skills rail (no JS) ---------- */
.section { padding: clamp(32px, 5vw, 72px) 0; }
.section-title {
  font-size: clamp(22px, 2.6vw, 36px);
  font-weight: 700; letter-spacing: .2px;
  margin-bottom: 24px;
}

.skills-grid {
  --cols: 6;
  display: grid;
  grid-template-columns: repeat(var(--cols), minmax(0, 1fr));
  gap: 18px;
  list-style: none;
  padding: 0; margin: 0;
}
@media (max-width: 1200px){ .skills-grid { --cols: 5; } }
@media (max-width: 980px){ .skills-grid { --cols: 4; } }
@media (max-width: 760px){ .skills-grid { --cols: 3; } }
@media (max-width: 520px){ .skills-grid { --cols: 2; } }

.skill-card {
  backdrop-filter: blur(14px);
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.14);
  border-radius: 18px;
  box-shadow: 0 12px 32px rgba(0,0,0,.35);
  padding: 16px 12px;
  text-align: center;
  transition: transform .2s ease, border-color .2s ease, background .2s ease;
}
.skill-card:hover {
  transform: translateY(-2px);
  border-color: rgba(125,211,252,.5);
  background: rgba(255,255,255,.08);
}

.skill-icon {
  display: block;
  height: 64px; width: 64px;
  margin: 6px auto 10px;
  object-fit: contain;
  image-rendering: -webkit-optimize-contrast;
}
.skill-card span {
  font-size: 14px;
  color: #ececf1;
  opacity: .95;
}
.rail { overflow: auto hidden; }
.rail-track { display: grid; grid-auto-flow: column; grid-auto-columns: minmax(160px, 1fr); gap: 14px; padding-bottom: 6px; }
.skill-card { display: grid; justify-items: center; gap: .5rem; padding: 14px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-sm); }
.skill-card img { width: 56px; height: 56px; object-fit: contain; filter: saturate(105%); }
.skill-card span { font-size: .92rem; color: var(--ink); }

/* ---------- Timeline ---------- */
.timeline { position: relative; display: grid; gap: 18px; }
.timeline::before { content: ""; position: absolute; left: 12px; top: 0; bottom: 0; width: 2px; background: linear-gradient(180deg, var(--border), transparent); }
.tl-item { position: relative; display: grid; grid-template-columns: 36px 1fr; gap: 12px; align-items: start; }
.tl-dot { width: 24px; height: 24px; border-radius: 999px; background: radial-gradient(65% 65% at 30% 30%, var(--brand) 0 60%, var(--brand-ink) 60% 100%); box-shadow: 0 0 18px var(--brand); margin-top: 6px; }
.tl-card { background: linear-gradient(180deg, rgba(255,255,255,.08), rgba(255,255,255,.04)); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 16px; box-shadow: var(--shadow-soft); }
.tl-card h3 { margin: 0 0 .35rem; font-size: 1.02rem; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--border); background: rgba(255,255,255,.03); backdrop-filter: blur(var(--blur)); -webkit-backdrop-filter: blur(var(--blur)); }
.footer-inner { display: flex; gap: 1rem; justify-content: space-between; align-items: center; padding: 18px 0; color: var(--muted); font-size: var(--step--1); }
.footer-inner .link { color: var(--muted); }

/* ---------- Responsive ---------- */
@media (max-width: 1100px){
  .cert-card { grid-column: span 6; }
}
@media (max-width: 720px){
  .nav-container { height: 56px; }
  .hero h1 { font-size: var(--step-3); }
  .cards-grid { grid-template-columns: repeat(6, 1fr); }
  .cert-card { grid-column: span 6; }
}

/* ---------- Accessibility ---------- */
:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; border-radius: 12px; }

/* ---------- Subtle scrollbars ---------- */
::-webkit-scrollbar { height: 10px; width: 10px; }
::-webkit-scrollbar-thumb { background: var(--surface-2); border-radius: 999px; border: 2px solid transparent; background-clip: padding-box; }
::-webkit-scrollbar-track { background: transparent; }