/* ============================================================
HFS – HUGUET FEDERAL SERVICES
Feuille de styles principale
Typographies : Cormorant Garamond (titres) + DM Sans (corps)
============================================================ */

/* ============================================================
VARIABLES & RESET
============================================================ */
:root {
/* Couleurs */
--color-primary: #00ADEF;
--color-primary-dark: #0095cc;
--color-primary-light: #e8f7fd;
--color-white: #ffffff;
--color-bg: #ffffff;
--color-bg-light: #f7f8fa;
--color-bg-dark: #0d1b2a;
--color-text: #1a2535;
--color-text-muted: #5a6a7e;
--color-border: #e2e6ea;
--color-border-light: #eef1f4;

/* Typographie */
--font-display: 'Open Sans', system-ui, sans-serif;
--font-body: 'Open Sans', system-ui, sans-serif;

/* Tailles */
--fs-xs: 0.75rem;
--fs-sm: 0.875rem;
--fs-base: 1rem;
--fs-md: 1.125rem;
--fs-lg: 1.375rem;
--fs-xl: 1.75rem;
--fs-2xl: 2.25rem;
--fs-3xl: 3rem;
--fs-4xl: 3.75rem;

/* Espacements */
--space-xs: 0.5rem;
--space-sm: 1rem;
--space-md: 1.5rem;
--space-lg: 2.5rem;
--space-xl: 4rem;
--space-2xl: 6rem;
--space-3xl: 8rem;

/* Layout */
--container-max: 1200px;
--container-pad: 2rem;
--header-h: 72px;

/* Effets */
--radius-sm: 4px;
--radius-md: 8px;
--shadow-sm: 0 1px 4px rgba(0,0,0,0.06);
--shadow-md: 0 4px 20px rgba(0,0,0,0.08);
--transition: 0.25s ease;
}

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

html {
scroll-behavior: smooth;
font-size: 16px;
-webkit-text-size-adjust: 100%;
}

body {
font-family: var(--font-body);
font-size: var(--fs-base);
color: var(--color-text);
background-color: var(--color-bg);
line-height: 1.7;
-webkit-font-smoothing: antialiased;
overflow-x: hidden;
}

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

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

ul { list-style: none; }

/* Focus visible pour accessibilité clavier */
:focus-visible {
outline: 2px solid var(--color-primary);
outline-offset: 3px;
border-radius: var(--radius-sm);
}

/* ============================================================
UTILITAIRES
============================================================ */
.container {
width: 100%;
max-width: var(--container-max);
margin: 0 auto;
padding: 0 var(--container-pad);
}

/* ============================================================
TYPOGRAPHIE
============================================================ */
h1, h2, h3 {
font-family: var(--font-display);
font-weight: 700;
line-height: 1.2;
letter-spacing: -0.01em;
color: var(--color-text);
}

h1 { font-size: clamp(2rem, 5vw, var(--fs-4xl)); font-weight: 700; }
h2 { font-size: clamp(1.6rem, 3vw, var(--fs-3xl)); font-weight: 700; }
h3 { font-size: var(--fs-lg); font-weight: 600; }

p { margin-bottom: 1rem; }
p:last-child { margin-bottom: 0; }

/* ============================================================
BOUTONS
============================================================ */
.btn {
display: inline-flex;
align-items: center;
gap: 0.5rem;
padding: 0.75rem 1.75rem;
font-family: var(--font-body);
font-size: var(--fs-sm);
font-weight: 500;
letter-spacing: 0.04em;
text-transform: uppercase;
border-radius: var(--radius-sm);
border: 1.5px solid transparent;
cursor: pointer;
transition: background var(--transition), color var(--transition), border-color var(--transition), box-shadow
var(--transition);
text-decoration: none;
}

.btn--primary {
background: var(--color-primary);
color: var(--color-white);
border-color: var(--color-primary);
}
.btn--primary:hover {
background: var(--color-primary-dark);
border-color: var(--color-primary-dark);
color: var(--color-white);
box-shadow: 0 4px 16px rgba(0,173,239,0.25);
}

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

.btn--full { width: 100%; justify-content: center; }

/* ============================================================
HEADER
============================================================ */
.header {
position: fixed;
top: 0;
left: 0;
right: 0;
z-index: 1000;
height: var(--header-h);
background: rgba(255,255,255,0.97);
border-bottom: 1px solid var(--color-border-light);
backdrop-filter: blur(6px);
transition: box-shadow var(--transition);
}

.header.is-scrolled {
box-shadow: var(--shadow-sm);
}

.header__inner {
height: 100%;
display: flex;
align-items: center;
justify-content: space-between;
gap: 2rem;
}

/* Logo */
.logo {
display: flex;
flex-direction: column;
line-height: 1;
text-decoration: none;
gap: 2px;
}
.logo__image {
height: 60px;
width: auto;
display: block;
object-fit: contain;
}

/* Navigation */
.nav__list {
display: flex;
align-items: center;
gap: 0.25rem;
}

.nav__link {
display: inline-block;
padding: 0.4rem 0.875rem;
font-size: var(--fs-sm);
font-weight: 400;
color: var(--color-text-muted);
text-decoration: none;
border-radius: var(--radius-sm);
letter-spacing: 0.02em;
transition: color var(--transition), background var(--transition);
}
.nav__link:hover, .nav__link.is-active {
color: var(--color-text);
background: var(--color-bg-light);
}

.nav__link--cta {
background: var(--color-primary);
color: var(--color-white) !important;
padding: 0.45rem 1.1rem;
font-weight: 500;
letter-spacing: 0.04em;
}
.nav__link--cta:hover {
background: var(--color-primary-dark) !important;
color: var(--color-white) !important;
}

/* Bouton menu mobile */
.nav-toggle {
display: none;
flex-direction: column;
gap: 5px;
padding: 8px;
background: none;
border: none;
cursor: pointer;
border-radius: var(--radius-sm);
}
.nav-toggle__bar {
display: block;
width: 22px;
height: 1.5px;
background: var(--color-text);
border-radius: 2px;
transition: transform var(--transition), opacity var(--transition);
transform-origin: center;
}
.nav-toggle.is-open .nav-toggle__bar:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-toggle.is-open .nav-toggle__bar:nth-child(2) { opacity: 0; }
.nav-toggle.is-open .nav-toggle__bar:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ============================================================
HERO
============================================================ */
.hero {
min-height: 100vh;
display: flex;
flex-direction: column;
justify-content: center;
padding-top: var(--header-h);
background: var(--color-white);
position: relative;
overflow: hidden;
}

/* Ligne décorative verticale gauche */
.hero::before {
content: '';
position: absolute;
left: 0;
top: 0;
bottom: 0;
width: 3px;
background: linear-gradient(to bottom, transparent, var(--color-primary) 30%, var(--color-primary) 70%, transparent);
opacity: 0.35;
}

.hero__grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: var(--space-xl);
align-items: center;
padding-top: var(--space-xl);
padding-bottom: var(--space-xl);
}

.hero__content {
max-width: 580px;
}

.hero__overline {
font-size: var(--fs-xs);
font-weight: 500;
letter-spacing: 0.18em;
text-transform: uppercase;
color: var(--color-primary);
margin-bottom: var(--space-md);
display: flex;
align-items: center;
gap: 0.75rem;
}
.hero__overline::before {
content: '';
display: inline-block;
width: 28px;
height: 1px;
background: var(--color-primary);
}

.hero__title {
margin-bottom: var(--space-md);
color: var(--color-text);
}

.hero__lead {
font-size: var(--fs-md);
color: var(--color-text-muted);
line-height: 1.75;
margin-bottom: var(--space-lg);
font-weight: 300;
}

.hero__actions {
display: flex;
gap: 1rem;
flex-wrap: wrap;
}

/* Graphique abstrait CSS */
.hero__graphic {
display: flex;
align-items: center;
justify-content: center;
}

.structure-graphic {
position: relative;
width: 320px;
height: 320px;
}

/* Anneaux */
.sg__ring {
position: absolute;
border-radius: 50%;
border: 1px solid var(--color-primary);
top: 50%; left: 50%;
transform: translate(-50%, -50%);
animation: ring-pulse 4s ease-in-out infinite;
}
.sg__ring--1 {
width: 200px; height: 200px;
opacity: 0.12;
}
.sg__ring--2 {
width: 300px; height: 300px;
opacity: 0.06;
animation-delay: 1s;
}

@keyframes ring-pulse {
0%, 100% { opacity: 0.06; }
50% { opacity: 0.18; }
}

/* Nœud central */
.sg__node {
position: absolute;
border-radius: 50%;
background: var(--color-primary);
}
.sg__node--center {
width: 18px; height: 18px;
top: 50%; left: 50%;
transform: translate(-50%, -50%);
box-shadow: 0 0 0 6px rgba(0,173,239,0.12);
}

/* Lignes & nœuds satellites */
.sg__line {
position: absolute;
top: 50%; left: 50%;
width: 90px;
height: 1px;
background: linear-gradient(to right, var(--color-primary), rgba(0,173,239,0.2));
transform-origin: left center;
opacity: 0.45;
}
.sg__line--1 { transform: translateY(-50%) rotate(-40deg); }
.sg__line--2 { transform: translateY(-50%) rotate(70deg); }
.sg__line--3 { transform: translateY(-50%) rotate(180deg); }

.sg__node--1, .sg__node--2, .sg__node--3 {
width: 10px; height: 10px;
background: var(--color-primary);
opacity: 0.6;
}
.sg__node--1 { top: 22%; left: 68%; }
.sg__node--2 { top: 72%; left: 72%; }
.sg__node--3 { top: 50%; left: 18%; }

/* Indicateur scroll */
.hero__indicator {
position: absolute;
bottom: 2.5rem;
left: 50%;
transform: translateX(-50%);
display: flex;
flex-direction: column;
align-items: center;
gap: 0.5rem;
}
.hero__scroll-label {
font-size: var(--fs-xs);
letter-spacing: 0.14em;
text-transform: uppercase;
color: var(--color-text-muted);
}
.hero__scroll-line {
width: 1px;
height: 36px;
background: linear-gradient(to bottom, var(--color-border), transparent);
animation: scroll-line 2s ease-in-out infinite;
}
@keyframes scroll-line {
0%, 100% { opacity: 0.4; transform: scaleY(1); }
50% { opacity: 1; transform: scaleY(1.15); }
}

/* ============================================================
SECTIONS — STRUCTURE COMMUNE
============================================================ */
.section {
padding: var(--space-3xl) 0;
}
.section--light { background: var(--color-bg-light); }
.section--dark {
background: var(--color-bg-dark);
color: rgba(255,255,255,0.88);
}
.section--dark h2, .section--dark h3 { color: var(--color-white); }
.section--dark p { color: rgba(255,255,255,0.68); }

/* En-tête de section */
.section-header {
margin-bottom: var(--space-xl);
max-width: 680px;
}
.section-header--center {
text-align: center;
margin-left: auto;
margin-right: auto;
}

.section-header__tag {
display: inline-block;
font-size: var(--fs-xs);
font-weight: 500;
letter-spacing: 0.2em;
text-transform: uppercase;
color: var(--color-primary);
margin-bottom: 0.75rem;
}
.section-header__tag--light { color: rgba(0,173,239,0.75); }

.section-header__title {
margin-bottom: 1rem;
font-weight: 700;
}

.section-header__sub {
font-size: var(--fs-md);
color: var(--color-text-muted);
font-weight: 300;
line-height: 1.7;
}
.section--dark .section-header__sub { color: rgba(255,255,255,0.55); }

/* ============================================================
À PROPOS
============================================================ */
.about__grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: var(--space-xl);
align-items: start;
}

.about__text p {
color: var(--color-text-muted);
line-height: 1.8;
}
.about__text .about__lead {
font-size: var(--fs-md);
color: var(--color-text);
font-weight: 400;
margin-bottom: var(--space-md);
}

/* Blocs statistiques / points clés */
.about__stats {
display: flex;
flex-direction: column;
gap: var(--space-md);
}

.stat-block {
display: flex;
gap: 1.25rem;
padding: var(--space-md);
background: var(--color-white);
border: 1px solid var(--color-border-light);
border-radius: var(--radius-md);
box-shadow: var(--shadow-sm);
transition: box-shadow var(--transition), border-color var(--transition);
}
.stat-block:hover {
box-shadow: var(--shadow-md);
border-color: var(--color-primary-light);
}

.stat-block__icon {
flex-shrink: 0;
width: 48px; height: 48px;
display: flex;
align-items: center;
justify-content: center;
background: var(--color-primary-light);
border-radius: var(--radius-sm);
color: var(--color-primary);
}

.stat-block__title {
font-weight: 500;
font-size: var(--fs-sm);
margin-bottom: 0.35rem;
color: var(--color-text);
}
.stat-block__desc {
font-size: var(--fs-sm);
color: var(--color-text-muted);
margin: 0;
line-height: 1.6;
}

/* ============================================================
MISSIONS
============================================================ */
.missions__grid {
display: grid;
grid-template-columns: repeat(3, 1fr);
gap: 1.5rem;
}

.mission-card {
padding: var(--space-lg) var(--space-md);
background: var(--color-white);
border: 1px solid var(--color-border-light);
border-radius: var(--radius-md);
box-shadow: var(--shadow-sm);
transition: box-shadow var(--transition), border-color var(--transition), transform var(--transition);
position: relative;
overflow: hidden;
}

/* Accent coloré en haut */
.mission-card::before {
content: '';
position: absolute;
top: 0; left: 0; right: 0;
height: 2px;
background: var(--color-primary);
transform: scaleX(0);
transform-origin: left;
transition: transform 0.35s ease;
}
.mission-card:hover::before { transform: scaleX(1); }

.mission-card:hover {
box-shadow: var(--shadow-md);
border-color: rgba(0,173,239,0.15);
transform: translateY(-2px);
}

.mission-card__icon {
display: inline-flex;
align-items: center;
justify-content: center;
width: 44px; height: 44px;
background: var(--color-primary-light);
border-radius: var(--radius-sm);
color: var(--color-primary);
margin-bottom: var(--space-md);
}

.mission-card__title {
font-size: var(--fs-base);
font-family: var(--font-body);
font-weight: 500;
margin-bottom: 0.75rem;
color: var(--color-text);
}

.mission-card__desc {
font-size: var(--fs-sm);
color: var(--color-text-muted);
line-height: 1.7;
margin: 0;
}

/* ============================================================
ENGAGEMENTS
============================================================ */
.engagements__grid {
display: grid;
grid-template-columns: repeat(3, 1fr);
gap: 2rem 3rem;
}

.engagement-item {
padding: var(--space-md) 0;
border-top: 1px solid var(--color-border);
position: relative;
}

.engagement-item__number {
font-family: var(--font-display);
font-size: 2rem;
font-weight: 700;
color: var(--color-primary);
opacity: 0.25;
line-height: 1;
margin-bottom: 0.5rem;
letter-spacing: 0.02em;
}

.engagement-item__title {
font-family: var(--font-body);
font-size: var(--fs-base);
font-weight: 500;
color: var(--color-text);
margin-bottom: 0.75rem;
letter-spacing: 0.01em;
}

.engagement-item__desc {
font-size: var(--fs-sm);
color: var(--color-text-muted);
line-height: 1.7;
margin: 0;
}

/* ============================================================
APPROCHE
============================================================ */
.approach__steps {
display: flex;
flex-direction: column;
gap: 0;
position: relative;
}

/* Ligne verticale reliant les étapes */
.approach__steps::before {
content: '';
position: absolute;
left: 34px;
top: 0; bottom: 0;
width: 1px;
background: linear-gradient(to bottom, rgba(0,173,239,0.3), rgba(0,173,239,0.05));
}

.approach-step {
display: grid;
grid-template-columns: 68px 1fr;
gap: var(--space-lg);
padding: var(--space-lg) 0;
border-bottom: 1px solid rgba(255,255,255,0.07);
position: relative;
}
.approach-step:last-child { border-bottom: none; }

.approach-step__num {
width: 68px;
height: 68px;
border-radius: 50%;
background: rgba(0,173,239,0.12);
border: 1px solid rgba(0,173,239,0.3);
display: flex;
align-items: center;
justify-content: center;
font-family: var(--font-display);
font-size: 1.25rem;
font-weight: 700;
color: var(--color-primary);
flex-shrink: 0;
position: relative;
z-index: 1;
}

.approach-step__content {
padding-top: 0.75rem;
}

.approach-step__title {
font-family: var(--font-body);
font-size: var(--fs-lg);
font-weight: 400;
color: var(--color-white);
margin-bottom: 0.75rem;
letter-spacing: 0.01em;
}

.approach-step__desc {
font-size: var(--fs-sm);
color: rgba(255,255,255,0.55);
line-height: 1.8;
margin: 0;
}

/* ============================================================
CONTACT
============================================================ */
.contact__grid {
display: grid;
grid-template-columns: 360px 1fr;
gap: var(--space-xl);
align-items: start;
}

/* Informations de contact */
.contact__info {
background: var(--color-bg-light);
border: 1px solid var(--color-border-light);
border-radius: var(--radius-md);
padding: var(--space-lg);
}

.contact-info-block {
padding-bottom: var(--space-md);
margin-bottom: var(--space-md);
border-bottom: 1px solid var(--color-border);
}
.contact-info-block__title {
font-family: var(--font-display);
font-size: var(--fs-xl);
font-weight: 700;
color: var(--color-text);
margin-bottom: 0.25rem;
}
.contact-info-block__group-tag {
font-size: var(--fs-xs);
letter-spacing: 0.14em;
text-transform: uppercase;
color: var(--color-primary);
margin: 0;
}

.contact-details { display: flex; flex-direction: column; gap: var(--space-md); }

.contact-details__item { display: flex; flex-direction: column; gap: 0.25rem; }

.contact-details__label {
display: flex;
align-items: center;
gap: 0.5rem;
font-size: var(--fs-xs);
font-weight: 500;
letter-spacing: 0.1em;
text-transform: uppercase;
color: var(--color-text-muted);
}
.contact-details__label svg { color: var(--color-primary); flex-shrink: 0; }

.contact-details__value {
font-size: var(--fs-sm);
color: var(--color-text);
line-height: 1.6;
padding-left: 1.5rem;
}
.contact-details__value a {
color: var(--color-text);
transition: color var(--transition);
}
.contact-details__value a:hover { color: var(--color-primary); }

.contact__note {
margin-top: var(--space-md);
padding-top: var(--space-md);
border-top: 1px solid var(--color-border);
}
.contact__note p {
font-size: var(--fs-xs);
color: var(--color-text-muted);
line-height: 1.7;
margin: 0;
}

/* Formulaire */
.contact__form-wrap {
background: var(--color-white);
border: 1px solid var(--color-border-light);
border-radius: var(--radius-md);
padding: var(--space-lg);
box-shadow: var(--shadow-sm);
}

.form-row--two {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 1rem;
}

.form-group { display: flex; flex-direction: column; gap: 0.4rem; margin-bottom: 1.25rem; }
.form-group:last-of-type { margin-bottom: 0; }

.form-label {
font-size: var(--fs-xs);
font-weight: 500;
letter-spacing: 0.08em;
text-transform: uppercase;
color: var(--color-text);
}
.form-label span { color: var(--color-primary); }

.form-input {
width: 100%;
padding: 0.75rem 1rem;
font-family: var(--font-body);
font-size: var(--fs-sm);
color: var(--color-text);
background: var(--color-white);
border: 1px solid var(--color-border);
border-radius: var(--radius-sm);
transition: border-color var(--transition), box-shadow var(--transition);
outline: none;
}
.form-input:focus {
border-color: var(--color-primary);
box-shadow: 0 0 0 3px rgba(0,173,239,0.1);
}
.form-input.is-invalid { border-color: #d9534f; }
.form-input--textarea { resize: vertical; min-height: 130px; }

.form-error {
font-size: var(--fs-xs);
color: #c0392b;
min-height: 1.2em;
display: block;
}

.form-required-note {
font-size: var(--fs-xs);
color: var(--color-text-muted);
margin-bottom: 1.25rem;
}
.form-required-note span { color: var(--color-primary); }

/* Message de succès */
.form-success {
text-align: center;
padding: var(--space-xl) var(--space-md);
}
.form-success__icon {
display: inline-flex;
align-items: center;
justify-content: center;
width: 68px; height: 68px;
border-radius: 50%;
background: var(--color-primary-light);
color: var(--color-primary);
margin: 0 auto var(--space-md);
}
.form-success__title {
font-size: var(--fs-2xl);
font-weight: 700;
margin-bottom: 0.75rem;
color: var(--color-text);
}
.form-success__desc {
color: var(--color-text-muted);
font-size: var(--fs-sm);
margin: 0;
}

/* ============================================================
FOOTER
============================================================ */
.footer {
background: #0a1520;
color: rgba(255,255,255,0.55);
padding: var(--space-xl) 0 var(--space-md);
}

.footer__top {
display: grid;
grid-template-columns: 1fr auto auto;
gap: var(--space-xl);
align-items: start;
padding-bottom: var(--space-lg);
border-bottom: 1px solid rgba(255,255,255,0.07);
margin-bottom: var(--space-md);
}

.footer__logo-image {
height: 120px;
width: auto;
display: block;
object-fit: contain;
margin-bottom: 0.6rem;
}
.footer__group-mention {
font-size: var(--fs-xs);
color: rgba(255,255,255,0.3);
margin: 0;
}

.footer__nav-list {
display: flex;
flex-direction: column;
gap: 0.5rem;
}
.footer__nav-link {
font-size: var(--fs-sm);
color: rgba(255,255,255,0.5);
text-decoration: none;
transition: color var(--transition);
}
.footer__nav-link:hover { color: var(--color-white); }

.footer__legal-links {
display: flex;
flex-direction: column;
gap: 0.5rem;
}
.footer__legal-link {
font-size: var(--fs-xs);
color: rgba(255,255,255,0.4);
text-decoration: none;
transition: color var(--transition);
}
.footer__legal-link:hover { color: rgba(255,255,255,0.75); }

.footer__bottom {
display: flex;
align-items: center;
justify-content: space-between;
}
.footer__copy, .footer__domain {
font-size: var(--fs-xs);
color: rgba(255,255,255,0.3);
margin: 0;
}
.footer__domain {
font-family: monospace;
letter-spacing: 0.05em;
}

/* ============================================================
BOUTON RETOUR EN HAUT
============================================================ */
.back-to-top {
position: fixed;
bottom: 2rem;
right: 2rem;
z-index: 500;
width: 44px; height: 44px;
border-radius: 50%;
background: var(--color-white);
border: 1px solid var(--color-border);
color: var(--color-text);
box-shadow: var(--shadow-md);
cursor: pointer;
display: flex;
align-items: center;
justify-content: center;
transition: background var(--transition), color var(--transition), box-shadow var(--transition), opacity
var(--transition), transform var(--transition);
opacity: 0;
transform: translateY(8px);
}
.back-to-top:not([hidden]) {
opacity: 1;
transform: translateY(0);
}
.back-to-top:hover {
background: var(--color-primary);
color: var(--color-white);
border-color: var(--color-primary);
box-shadow: 0 4px 16px rgba(0,173,239,0.3);
}

/* ============================================================
ANIMATIONS AU SCROLL
============================================================ */
.reveal {
opacity: 0;
transform: translateY(24px);
transition: opacity 0.65s ease, transform 0.65s ease;
}
.reveal.is-visible {
opacity: 1;
transform: translateY(0);
}

/* Délais en cascade pour les grilles */
.missions__grid .mission-card:nth-child(1) { transition-delay: 0.05s; }
.missions__grid .mission-card:nth-child(2) { transition-delay: 0.10s; }
.missions__grid .mission-card:nth-child(3) { transition-delay: 0.15s; }
.missions__grid .mission-card:nth-child(4) { transition-delay: 0.20s; }
.missions__grid .mission-card:nth-child(5) { transition-delay: 0.25s; }
.missions__grid .mission-card:nth-child(6) { transition-delay: 0.30s; }

.engagements__grid .engagement-item:nth-child(1) { transition-delay: 0.05s; }
.engagements__grid .engagement-item:nth-child(2) { transition-delay: 0.10s; }
.engagements__grid .engagement-item:nth-child(3) { transition-delay: 0.15s; }
.engagements__grid .engagement-item:nth-child(4) { transition-delay: 0.20s; }
.engagements__grid .engagement-item:nth-child(5) { transition-delay: 0.25s; }
.engagements__grid .engagement-item:nth-child(6) { transition-delay: 0.30s; }

.approach-step:nth-child(1) { transition-delay: 0.05s; }
.approach-step:nth-child(2) { transition-delay: 0.15s; }
.approach-step:nth-child(3) { transition-delay: 0.25s; }
.approach-step:nth-child(4) { transition-delay: 0.35s; }

/* ============================================================
RESPONSIVE — TABLETTE (≤ 1024px)
============================================================ */
@media (max-width: 1024px) {
:root {
--container-pad: 1.5rem;
--space-3xl: 5rem;
}

.hero__grid { grid-template-columns: 1fr; }
.hero__graphic { display: none; }
.hero__content { max-width: 100%; }

.about__grid { grid-template-columns: 1fr; }

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

.contact__grid { grid-template-columns: 1fr; }
.contact__info { order: 2; }

.footer__top { grid-template-columns: 1fr 1fr; }
.footer__brand { grid-column: 1 / -1; }
}

/* ============================================================
RESPONSIVE — MOBILE (≤ 768px)
============================================================ */
@media (max-width: 768px) {
:root {
--container-pad: 1.25rem;
--space-3xl: 4rem;
--space-xl: 2.5rem;
--header-h: 64px;
}

/* Header mobile */
.nav {
position: fixed;
top: var(--header-h);
left: 0; right: 0;
background: var(--color-white);
border-bottom: 1px solid var(--color-border-light);
box-shadow: var(--shadow-md);
padding: 1rem var(--container-pad) 1.5rem;
transform: translateY(-10px);
opacity: 0;
pointer-events: none;
transition: opacity var(--transition), transform var(--transition);
}
.nav.is-open {
opacity: 1;
transform: translateY(0);
pointer-events: all;
}
.nav__list { flex-direction: column; gap: 0.25rem; align-items: stretch; }
.nav__link { padding: 0.65rem 1rem; }
.nav-toggle { display: flex; }

/* Missions & Engagements */
.missions__grid { grid-template-columns: 1fr; }
.engagements__grid { grid-template-columns: 1fr; }

/* Approche */
.approach__steps::before { display: none; }
.approach-step { grid-template-columns: 1fr; gap: 1rem; }
.approach-step__num { width: 52px; height: 52px; font-size: 1.1rem; }

/* Contact */
.form-row--two { grid-template-columns: 1fr; }

/* Footer */
.footer__top { grid-template-columns: 1fr; }
.footer__bottom { flex-direction: column; gap: 0.5rem; text-align: center; }

/* Back to top */
.back-to-top { bottom: 1.25rem; right: 1.25rem; }
}

/* ============================================================
RESPONSIVE — PETIT MOBILE (≤ 480px)
============================================================ */
@media (max-width: 480px) {
:root { --container-pad: 1rem; }
.hero__actions { flex-direction: column; }
.hero__actions .btn { width: 100%; justify-content: center; }
}