/* ============ DESIGN TOKENS ============ */
:root {
  --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);
  --text-hero: clamp(3rem, 0.5rem + 7vw, 7rem);

  --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;

  --radius-sm: 0.375rem; --radius-md: 0.5rem; --radius-lg: 0.75rem;
  --radius-xl: 1rem; --radius-full: 9999px;

  --content-narrow: 640px; --content-default: 1000px; --content-wide: 1240px;
  --transition: 300ms cubic-bezier(0.16, 1, 0.3, 1);

  --font-display: 'Fraunces', Georgia, serif;
  --font-body: 'Inter', system-ui, sans-serif;

  /* Brand: fire & ice */
  --fire: #e8622a;
  --fire-soft: #f0894f;
  --ember: #c9461a;
  --ice: #5f9fc7;
  --ice-soft: #8fc4dd;
  --frost: #bfdeed;
}

/* DARK (default — fits the moody fire/ice direction) */
:root, [data-theme='dark'] {
  --color-bg: #0e0f13;
  --color-surface: #15171d;
  --color-surface-2: #1c1f27;
  --color-border: #2a2e38;
  --color-divider: #21242c;
  --color-text: #ecebe8;
  --color-text-muted: #9a9ba1;
  --color-text-faint: #5e616b;
  --color-text-inverse: #0e0f13;
  --color-primary: var(--fire);
  --color-primary-hover: var(--fire-soft);
  --color-accent: var(--ice);
  --shadow-md: 0 4px 24px rgba(0,0,0,0.4);
  --shadow-lg: 0 16px 48px rgba(0,0,0,0.55);
}

[data-theme='light'] {
  --color-bg: #f7f5f1;
  --color-surface: #ffffff;
  --color-surface-2: #f1eee8;
  --color-border: #e0dcd3;
  --color-divider: #e8e4dc;
  --color-text: #1c1d22;
  --color-text-muted: #5e616b;
  --color-text-faint: #a4a6ad;
  --color-text-inverse: #ffffff;
  --color-primary: var(--ember);
  --color-primary-hover: var(--fire);
  --color-accent: #2c7fa8;
  --shadow-md: 0 4px 20px rgba(40,30,20,0.08);
  --shadow-lg: 0 16px 40px rgba(40,30,20,0.12);
}

/* ============ BASE ============ */
*,*::before,*::after { box-sizing: border-box; margin: 0; padding: 0; }
html {
  -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility; scroll-behavior: smooth; scroll-padding-top: 5rem;
}
body {
  min-height: 100dvh; line-height: 1.65; font-family: var(--font-body);
  font-size: var(--text-base); color: var(--color-text); background: var(--color-bg);
  transition: background var(--transition), color var(--transition);
}
img,svg { display: block; max-width: 100%; height: auto; }
ul[role='list'] { list-style: none; }
button { cursor: pointer; background: none; border: none; font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }
h1,h2,h3,h4 { font-family: var(--font-display); text-wrap: balance; line-height: 1.1; font-weight: 500; }
p { text-wrap: pretty; }
::selection { background: var(--color-primary); color: #fff; }
:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 3px; border-radius: var(--radius-sm); }
@media (prefers-reduced-motion: reduce) {
  *,*::before,*::after { animation-duration: .01ms !important; transition-duration: .01ms !important; scroll-behavior: auto !important; }
}

/* ============ LAYOUT ============ */
.wrap { width: min(100% - 2.5rem, var(--content-wide)); margin-inline: auto; }
.wrap-narrow { width: min(100% - 2.5rem, var(--content-default)); margin-inline: auto; }
section { padding-block: clamp(var(--space-16), 9vw, var(--space-32)); }
.eyebrow {
  font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.18em;
  color: var(--color-primary); font-weight: 600; margin-bottom: var(--space-4);
  display: inline-flex; align-items: center; gap: var(--space-2);
}
.eyebrow::before { content:''; width: 28px; height: 1px; background: var(--color-primary); }

/* ============ HEADER ============ */
.header {
  position: sticky; top: 0; z-index: 100;
  background: color-mix(in oklab, var(--color-bg) 80%, transparent);
  backdrop-filter: blur(14px); border-bottom: 1px solid transparent;
  transition: border-color var(--transition), background var(--transition);
}
.header.scrolled { border-color: var(--color-divider); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 4.75rem; }
.logo { display: flex; align-items: center; gap: var(--space-3); font-family: var(--font-display); font-size: var(--text-lg); font-weight: 600; letter-spacing: -0.01em; }
.logo svg { width: 30px; height: 30px; flex-shrink: 0; }
.nav-links { display: flex; align-items: center; gap: var(--space-8); }
.nav-links a { font-size: var(--text-sm); color: var(--color-text-muted); transition: color var(--transition); }
.nav-links a:hover, .nav-links a.active { color: var(--color-text); }
.nav-right { display: flex; align-items: center; gap: var(--space-4); }
.theme-toggle { width: 38px; height: 38px; display: grid; place-items: center; border-radius: var(--radius-full); color: var(--color-text-muted); transition: color var(--transition), background var(--transition); }
.theme-toggle:hover { color: var(--color-text); background: var(--color-surface-2); }
.menu-btn { display: none; }

/* ============ BUTTONS ============ */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  font-size: var(--text-sm); font-weight: 600; padding: 0.8rem 1.5rem;
  border-radius: var(--radius-full); transition: all var(--transition); white-space: nowrap;
}
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:hover { background: var(--color-primary-hover); transform: translateY(-2px); box-shadow: 0 8px 24px color-mix(in oklab, var(--color-primary) 40%, transparent); }
.btn-ghost { border: 1px solid var(--color-border); color: var(--color-text); }
.btn-ghost:hover { border-color: var(--color-primary); color: var(--color-primary); }
.btn-lg { padding: 1rem 2rem; font-size: var(--text-base); }

/* ============ HERO ============ */
.hero { position: relative; min-height: 92vh; display: flex; align-items: center; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; z-index: 0; }
.hero-bg img { width: 100%; height: 100%; object-fit: cover; }
.hero-bg::after { content:''; position: absolute; inset: 0; background: linear-gradient(90deg, var(--color-bg) 8%, color-mix(in oklab, var(--color-bg) 55%, transparent) 45%, color-mix(in oklab, var(--color-bg) 30%, transparent) 100%); }
[data-theme='light'] .hero-bg::after { background: linear-gradient(90deg, var(--color-bg) 8%, color-mix(in oklab, var(--color-bg) 65%, transparent) 48%, color-mix(in oklab, var(--color-bg) 40%, transparent) 100%); }
.hero-content { position: relative; z-index: 1; max-width: 760px; }
.hero h1 { font-size: var(--text-hero); letter-spacing: -0.02em; margin-bottom: var(--space-6); }
.hero h1 .fire-word { color: var(--fire); font-style: italic; }
.hero h1 .ice-word { color: var(--ice); font-style: italic; }
.hero-sub { font-size: var(--text-lg); color: var(--color-text-muted); max-width: 56ch; margin-bottom: var(--space-8); }
.hero-cta { display: flex; gap: var(--space-4); flex-wrap: wrap; }
.hero-tags { display: flex; gap: var(--space-5); flex-wrap: wrap; margin-top: var(--space-12); font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.14em; color: var(--color-text-faint); }
.hero-tags span { display: flex; align-items: center; gap: var(--space-2); }
.hero-tags span::before { content:''; width: 5px; height: 5px; border-radius: 50%; background: var(--color-primary); }

/* ============ SECTION HEADINGS ============ */
.sec-head { max-width: 640px; margin-bottom: var(--space-12); }
.sec-head.center { margin-inline: auto; text-align: center; }
.sec-head h2 { font-size: var(--text-2xl); letter-spacing: -0.01em; margin-bottom: var(--space-4); }
.sec-head p { color: var(--color-text-muted); font-size: var(--text-lg); }

/* ============ INTRO / PROBLEM ============ */
.intro-grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(var(--space-8), 6vw, var(--space-24)); align-items: center; }
.intro-grid .lead { font-family: var(--font-display); font-size: var(--text-xl); line-height: 1.3; }
.intro-grid .lead em { color: var(--color-primary); font-style: italic; }
.stat-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-6); margin-top: var(--space-8); }
.stat { padding: var(--space-6); border: 1px solid var(--color-border); border-radius: var(--radius-lg); background: var(--color-surface); }
.stat .num { font-family: var(--font-display); font-size: var(--text-2xl); color: var(--color-primary); line-height: 1; }
.stat .lbl { font-size: var(--text-sm); color: var(--color-text-muted); margin-top: var(--space-2); }

/* ============ PREUVES SCIENTIFIQUES ============ */
.proof-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-6); margin-top: var(--space-12); }
.proof {
  padding: var(--space-8);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-surface);
  position: relative;
  overflow: hidden;
}
.proof::before {
  content: '';
  position: absolute; inset: 0 auto 0 0; width: 4px;
  background: linear-gradient(180deg, var(--fire), var(--ice));
}
.proof-num {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  line-height: 1;
  color: var(--color-primary);
  letter-spacing: -0.02em;
}
.proof-num .unit { font-size: 0.5em; margin-left: 0.1em; opacity: 0.85; }
.proof-title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  margin-top: var(--space-3);
  color: var(--color-text);
}
.proof-title sup a {
  font-size: 0.6em; color: var(--color-primary); text-decoration: none;
  padding-left: 2px; font-family: var(--font-body, inherit);
}
.proof-title sup a:hover { text-decoration: underline; }
.proof-desc { font-size: var(--text-sm); color: var(--color-text-muted); margin-top: var(--space-4); line-height: 1.6; }
.refs {
  list-style: decimal;
  margin: var(--space-10) 0 0;
  padding-left: 1.2em;
  max-width: 70ch;
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  line-height: 1.6;
}
.refs li { margin-bottom: var(--space-2); }
.refs li em { font-style: italic; }

/* ============ ARC / METHOD ============ */
.arc { background: var(--color-surface); }
.arc-steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-6); margin-top: var(--space-12); }
.arc-card { border-radius: var(--radius-lg); overflow: hidden; background: var(--color-bg); border: 1px solid var(--color-border); transition: transform var(--transition), border-color var(--transition); }
.arc-card:hover { transform: translateY(-6px); border-color: var(--color-primary); }
.arc-card .img { aspect-ratio: 4/3; overflow: hidden; }
.arc-card .img img { width: 100%; height: 100%; object-fit: cover; transition: transform 600ms var(--transition); }
.arc-card:hover .img img { transform: scale(1.06); }
.arc-card .body { padding: var(--space-6); }
.arc-step-n { font-family: var(--font-display); font-size: var(--text-sm); color: var(--color-primary); font-weight: 600; letter-spacing: 0.05em; }
.arc-card h3 { font-size: var(--text-lg); margin: var(--space-2) 0 var(--space-3); }
.arc-card p { font-size: var(--text-sm); color: var(--color-text-muted); }

/* ============ OFFERS ============ */
.offers-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-6); margin-top: var(--space-12); }
.offer { display: flex; flex-direction: column; padding: var(--space-8); border: 1px solid var(--color-border); border-radius: var(--radius-xl); background: var(--color-surface); transition: transform var(--transition), border-color var(--transition); position: relative; }
.offer.featured { border-color: var(--color-primary); }
.offer.featured::before { content:'Signature'; position: absolute; top: -0.75rem; left: var(--space-8); background: var(--color-primary); color:#fff; font-size: var(--text-xs); font-weight: 600; padding: 0.25rem 0.75rem; border-radius: var(--radius-full); text-transform: uppercase; letter-spacing: 0.08em; }
.offer:hover { transform: translateY(-6px); }
.offer h3 { font-size: var(--text-xl); margin-bottom: var(--space-2); }
.offer .format { font-size: var(--text-sm); color: var(--color-text-faint); margin-bottom: var(--space-5); }
.offer .desc { font-size: var(--text-sm); color: var(--color-text-muted); margin-bottom: var(--space-6); flex-grow: 1; }
.offer ul { list-style: none; display: flex; flex-direction: column; gap: var(--space-3); margin-bottom: var(--space-8); }
.offer li { font-size: var(--text-sm); display: flex; gap: var(--space-3); align-items: flex-start; }
.offer li svg { width: 18px; height: 18px; color: var(--color-primary); flex-shrink: 0; margin-top: 2px; }
.offer .price { font-family: var(--font-display); font-size: var(--text-lg); margin-bottom: var(--space-5); }
.offer .price span { font-size: var(--text-sm); color: var(--color-text-faint); font-family: var(--font-body); }

/* ============ SPLIT FEATURE ============ */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(var(--space-8), 6vw, var(--space-20)); align-items: center; }
.split.rev .split-text { order: 2; }
.split-img { border-radius: var(--radius-xl); overflow: hidden; aspect-ratio: 4/3; box-shadow: var(--shadow-lg); }
.split-img img { width: 100%; height: 100%; object-fit: cover; }
.split-text h2 { font-size: var(--text-2xl); margin-bottom: var(--space-5); letter-spacing: -0.01em; }
.split-text p { color: var(--color-text-muted); margin-bottom: var(--space-5); }
.check-list { list-style: none; display: flex; flex-direction: column; gap: var(--space-3); margin-top: var(--space-6); }
.check-list li { display: flex; gap: var(--space-3); font-size: var(--text-base); }
.check-list svg { width: 20px; height: 20px; color: var(--color-primary); flex-shrink: 0; margin-top: 3px; }

/* ============ TESTIMONIAL ============ */
.quote { background: var(--color-surface); }
.quote blockquote { font-family: var(--font-display); font-size: var(--text-2xl); line-height: 1.3; text-align: center; max-width: 900px; margin-inline: auto; }
.quote .attr { text-align: center; margin-top: var(--space-8); font-size: var(--text-sm); color: var(--color-text-muted); }

/* ============ CTA BANNER ============ */
.cta-banner { position: relative; overflow: hidden; border-radius: var(--radius-xl); padding: clamp(var(--space-12), 8vw, var(--space-24)); text-align: center; }
.cta-banner-bg { position: absolute; inset: 0; z-index: 0; }
.cta-banner-bg img { width: 100%; height: 100%; object-fit: cover; }
.cta-banner-bg::after { content:''; position: absolute; inset: 0; background: color-mix(in oklab, var(--color-bg) 72%, transparent); }
.cta-banner > * { position: relative; z-index: 1; }
.cta-banner h2 { font-size: var(--text-2xl); margin-bottom: var(--space-4); }
.cta-banner p { color: var(--color-text-muted); margin-bottom: var(--space-8); max-width: 50ch; margin-inline: auto; }

/* ============ FOOTER ============ */
.footer { border-top: 1px solid var(--color-divider); padding-block: var(--space-16) var(--space-8); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: var(--space-12); margin-bottom: var(--space-12); }
.footer-brand p { color: var(--color-text-muted); font-size: var(--text-sm); max-width: 36ch; margin-top: var(--space-4); }
.footer h4 { font-family: var(--font-body); font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.12em; color: var(--color-text-faint); margin-bottom: var(--space-4); font-weight: 600; }
.footer ul { list-style: none; display: flex; flex-direction: column; gap: var(--space-3); }
.footer ul a { font-size: var(--text-sm); color: var(--color-text-muted); }
.footer ul a:hover { color: var(--color-text); }
.footer-bottom { border-top: 1px solid var(--color-divider); padding-top: var(--space-8); display: flex; justify-content: space-between; flex-wrap: wrap; gap: var(--space-4); font-size: var(--text-xs); color: var(--color-text-faint); }

/* ============ PAGE HEADER (interior) ============ */
.page-head { padding-block: clamp(var(--space-16), 10vw, var(--space-24)) var(--space-12); border-bottom: 1px solid var(--color-divider); }
.page-head h1 { font-size: var(--text-3xl); letter-spacing: -0.02em; margin-bottom: var(--space-5); }
.page-head p { font-size: var(--text-lg); color: var(--color-text-muted); max-width: 60ch; }

/* ============ ABOUT ============ */
.cred-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: var(--space-5); margin-top: var(--space-8); }
.cred { padding: var(--space-6); border: 1px solid var(--color-border); border-radius: var(--radius-lg); background: var(--color-surface); }
.cred .icon { width: 40px; height: 40px; border-radius: var(--radius-md); background: color-mix(in oklab, var(--color-primary) 15%, transparent); color: var(--color-primary); display: grid; place-items: center; margin-bottom: var(--space-4); }
.cred h3 { font-family: var(--font-body); font-size: var(--text-base); font-weight: 600; margin-bottom: var(--space-2); }
.cred p { font-size: var(--text-sm); color: var(--color-text-muted); }

/* ============ FORM ============ */
.form-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: clamp(var(--space-8), 6vw, var(--space-20)); align-items: start; }
.form-card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-xl); padding: clamp(var(--space-6), 4vw, var(--space-10)); }
.field { margin-bottom: var(--space-5); }
.field label { display: block; font-size: var(--text-sm); font-weight: 600; margin-bottom: var(--space-2); }
.field input, .field select, .field textarea {
  width: 100%; padding: 0.8rem 1rem; border: 1px solid var(--color-border);
  border-radius: var(--radius-md); background: var(--color-bg); color: var(--color-text);
  font-size: var(--text-sm); transition: border-color var(--transition);
}
.field input:focus, .field select:focus, .field textarea:focus { outline: none; border-color: var(--color-primary); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
.form-aside h3 { font-size: var(--text-xl); margin-bottom: var(--space-5); }
.form-aside .step { display: flex; gap: var(--space-4); margin-bottom: var(--space-6); }
.form-aside .step-n { width: 32px; height: 32px; border-radius: 50%; background: color-mix(in oklab, var(--color-primary) 15%, transparent); color: var(--color-primary); display: grid; place-items: center; font-weight: 600; font-size: var(--text-sm); flex-shrink: 0; }
.form-aside .step h4 { font-family: var(--font-body); font-size: var(--text-base); margin-bottom: var(--space-1); }
.form-aside .step p { font-size: var(--text-sm); color: var(--color-text-muted); }
.form-note { font-size: var(--text-xs); color: var(--color-text-faint); margin-top: var(--space-4); }

/* ============ SESSIONS (booking) ============ */
.session { display: flex; align-items: center; gap: var(--space-6); padding: var(--space-6); border: 1px solid var(--color-border); border-radius: var(--radius-lg); background: var(--color-surface); margin-bottom: var(--space-4); flex-wrap: wrap; }
.session .date { font-family: var(--font-display); font-size: var(--text-lg); color: var(--color-primary); min-width: 90px; }
.session .info { flex-grow: 1; min-width: 200px; }
.session .info h3 { font-family: var(--font-body); font-size: var(--text-base); font-weight: 600; }
.session .info p { font-size: var(--text-sm); color: var(--color-text-muted); }
.session .seats { font-size: var(--text-xs); color: var(--color-text-faint); }

/* ============ PHOTO STRIP ============ */
.photo-strip { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); margin-top: var(--space-12); }
.photo-strip figure { margin: 0; border-radius: var(--radius-lg); overflow: hidden; position: relative; }
.photo-strip img { width: 100%; height: 100%; object-fit: cover; aspect-ratio: 16/10; transition: transform 600ms var(--transition); }
.photo-strip figure:hover img { transform: scale(1.05); }
.photo-strip figcaption { position: absolute; left: 0; right: 0; bottom: 0; padding: var(--space-5) var(--space-5) var(--space-4); font-size: var(--text-sm); color: #fff; background: linear-gradient(transparent, rgba(0,0,0,0.72)); }

/* ============ REVEAL ANIMATION ============ */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 700ms var(--transition), transform 700ms var(--transition); }
.reveal.in { opacity: 1; transform: none; }

/* ============ RESPONSIVE ============ */
@media (max-width: 880px) {
  .nav-links { display: none; }
  .menu-btn { display: grid; place-items: center; width: 38px; height: 38px; color: var(--color-text); }
  .intro-grid, .arc-steps, .offers-grid, .split, .split.rev .split-text, .form-grid, .footer-grid, .photo-strip, .proof-row { grid-template-columns: 1fr; }
  .split.rev .split-text { order: 0; }
  .stat-row { grid-template-columns: 1fr 1fr; }
  .footer-grid { gap: var(--space-8); }
  .nav-links.open { display: flex; position: absolute; top: 4.75rem; left: 0; right: 0; flex-direction: column; align-items: flex-start; gap: var(--space-5); padding: var(--space-6) 1.25rem; background: var(--color-bg); border-bottom: 1px solid var(--color-divider); }
}