/* ===== Design tokens ===== */
:root {
  --bg: #ffffff;
  --bg-alt: #f5f6f8;
  --text: #1a1d23;
  --text-muted: #5b6270;
  --primary: #3454d1;
  --primary-dark: #2a41a8;
  --border: #e3e5ea;
  --card-shadow: 0 1px 3px rgba(20, 22, 30, 0.06), 0 8px 24px rgba(20, 22, 30, 0.04);
  --radius: 12px;
  --max-width: 1080px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161c;
    --bg-alt: #1b1e26;
    --text: #eef0f4;
    --text-muted: #a2a8b6;
    --primary: #6d8cff;
    --primary-dark: #8ba0ff;
    --border: #2a2e38;
    --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.25);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Header / nav ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text);
}
.brand:hover { text-decoration: none; }

.nav-links {
  display: flex;
  gap: 28px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text);
  text-decoration: none;
}

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 10px;
  color: var(--text);
  font-size: 1.1rem;
  cursor: pointer;
}

@media (max-width: 680px) {
  .nav-toggle { display: inline-flex; }
  .nav-links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    gap: 0;
    padding: 8px 24px 16px;
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links li { padding: 10px 0; border-bottom: 1px solid var(--border); }
  .nav-links li:last-child { border-bottom: none; }
}

/* ===== Hero ===== */
.hero {
  padding: 96px 0 64px;
  text-align: left;
}

.hero .eyebrow {
  color: var(--primary);
  font-weight: 600;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  margin: 12px 0 16px;
  letter-spacing: -0.02em;
}

.hero p.lead {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 620px;
}

.hero .actions {
  display: flex;
  gap: 14px;
  margin-top: 28px;
  flex-wrap: wrap;
}

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  border: 1px solid transparent;
}
.btn:hover { text-decoration: none; }

.btn-primary {
  background: var(--primary);
  color: #fff;
}
.btn-primary:hover { background: var(--primary-dark); }

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

/* ===== Sections ===== */
section { padding: 56px 0; }

.section-title {
  font-size: 1.7rem;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.section-subtitle {
  color: var(--text-muted);
  margin-bottom: 36px;
  max-width: 620px;
}

/* ===== Cards / grid ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

.card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.card h3 { margin: 0; font-size: 1.05rem; }
.card p { margin: 0; color: var(--text-muted); font-size: 0.92rem; flex-grow: 1; }

.tag-row { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 4px; }
.tag {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--primary);
  background: color-mix(in srgb, var(--primary) 12%, transparent);
  padding: 3px 9px;
  border-radius: 999px;
}

.card-link {
  margin-top: 10px;
  font-weight: 600;
  font-size: 0.9rem;
}

/* ===== Skills list ===== */
.skills-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.skill-pill {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 8px 16px;
  font-size: 0.88rem;
  color: var(--text);
}

/* ===== Contact ===== */
.contact-links {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  margin-top: 8px;
}

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0;
  color: var(--text-muted);
  font-size: 0.88rem;
  text-align: center;
}

/* ===== App tool pages ===== */
.tool-shell {
  max-width: 560px;
  margin: 48px auto;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: var(--card-shadow);
}

.tool-shell h1 {
  font-size: 1.5rem;
  margin-top: 0;
}

.tool-back {
  display: inline-block;
  margin-bottom: 24px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.field { margin-bottom: 18px; }
.field label {
  display: block;
  font-weight: 600;
  font-size: 0.88rem;
  margin-bottom: 6px;
}
.field input[type="text"],
.field input[type="number"],
.field select {
  width: 100%;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 0.95rem;
}
.field-row { display: flex; gap: 12px; }
.field-row .field { flex: 1; }

.checkbox-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  font-size: 0.9rem;
}

.result-box {
  margin-top: 20px;
  padding: 16px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 1rem;
  word-break: break-all;
}

.result-box.empty { color: var(--text-muted); font-family: inherit; font-size: 0.9rem; }

/* ===== Publications ===== */
.pub-card h3 { font-size: 1rem; line-height: 1.4; }
.pub-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
}
.pub-venue { font-style: italic; }
.pub-cites {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--primary);
}

/* ===== Bac à sable (hidden menu) ===== */
.sandbox-toggle {
  margin-top: 28px;
  max-width: 360px;
}
.sandbox-toggle summary {
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-alt);
  font-weight: 600;
  font-size: 0.92rem;
  list-style: none;
  user-select: none;
}
.sandbox-toggle summary::-webkit-details-marker { display: none; }
.sandbox-toggle summary:hover { border-color: var(--primary); color: var(--primary); }
.sandbox-panel {
  margin-top: 14px;
  padding: 20px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-alt);
  box-shadow: var(--card-shadow);
}
.sandbox-panel p { color: var(--text-muted); margin-top: 0; font-size: 0.9rem; }
.sandbox-panel .field { max-width: 240px; }

.lock-error {
  color: #c0392b;
  font-size: 0.85rem;
  margin: 8px 0 0;
}