:root {
    --bg: #f4f3f1; /* blanc minéral, légèrement chaud */
    --fg: #1c1d1f; /* gris profond, pas noir pur */
    --muted: #7a7a7a; /* gris béton */
    --line: #dedbd6; /* ligne pierre */
    --surface: #ffffff; /* cartes */
    --accent: #2b2d31; /* accent discret */
    --max: 760px;
}

* {
    box-sizing: border-box;
}

html, body {
    height: 100%;
}

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

.hero-structured {
    display: flex;
    align-items: flex-start;
    gap: 4rem;
    margin-bottom: 2rem;
}

.hero-text h1 {
    margin: 0;
    font-size: 2.3rem;
    font-weight: 600;
    letter-spacing: 0.2px;
}

.logo-left {
    width: 200px;
    flex-shrink: 0;
}

.hero-text h1 {
    font-size: 2.4rem;
    font-weight: 500;
    line-height: 1.15;
    letter-spacing: -0.5px;
    margin: 0 0 1rem 0;
}

.subtitle {
    margin: 0 0 2rem 0;
    color: var(--muted);
    font-size: 1rem;
}

.section {
    max-width: 620px;
    margin-top: 0;
}

.section h2 {
    margin: 0 0 0.9rem 0;
    font-size: 1.15rem;
    font-weight: 550;
    color: var(--fg);
}

.container {
    max-width: var(--max);
    margin: 0 auto;
    padding: 3.75rem 1.5rem 3rem;
}

.hero h1 {
    margin: 0;
    font-size: 2.3rem;
    font-weight: 600;
    letter-spacing: 0.2px;
}

.subtitle {
    margin: 0.7rem 0 0 0;
    color: var(--muted);
    font-size: 1rem;
}

.topbar {
    position: fixed;
    top: 1.1rem;
    right: 1.5rem;
    font-size: 0.85rem;
    color: var(--muted);
    z-index: 50;
}

.topbar a {
    color: var(--muted);
    text-decoration: none;
    border-bottom: 1px solid transparent;
}

.topbar a:hover {
    color: var(--fg);
    border-bottom-color: var(--fg);
}

.topbar span {
    margin: 0 0.45rem;
    color: var(--muted);
}

.nav {
    margin-top: 1.5rem;
    margin-bottom: 3rem;
    padding-top: 1rem;
    padding-bottom: 1rem;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    opacity: 0.85;
}

.nav a {
    color: var(--muted);
    text-decoration: none;
    border-bottom: 1px solid transparent;
}

.nav a:hover {
    color: var(--fg);
    border-bottom-color: var(--fg);
    opacity: 1;
}

p {
    margin: 0 0 1rem 0;
}

strong {
    font-weight: 650;
}

ul {
    margin: 0;
    padding-left: 1.2rem;
}

li {
    margin: 0.45rem 0;
    color: var(--fg);
}

.card {
    margin-top: 2rem;
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 1.25rem 1.25rem;
}

.quote {
    margin-top: 2rem;
    border-left: 2px solid var(--line);
    color: var(--muted);
    padding-left: 1rem;
    font-style: italic;
}

.footer {
    margin-top: 3.2rem;
    padding-top: 1.2rem;
    border-top: 1px solid var(--line);
    color: var(--muted);
    font-size: 0.85rem;
}

.links a,
.note-list a {
    color: var(--accent);
    border-bottom: 1px solid var(--line);
}

.links a:hover,
.note-list a:hover {
    border-bottom-color: var(--fg);
}

.sep {
    color: var(--muted);
    padding: 0 0.35rem;
}

.note-list a {
    color: var(--fg);
    text-decoration: none;
    border-bottom: 1px solid var(--muted);
}

.note-list a:hover {
    border-bottom-color: var(--fg);
}

.small {
    color: var(--muted);
    font-size: 0.9rem;
}

.hr {
    border: 0;
    border-top: 1px solid var(--line);
    margin: 1.6rem 0;
}

.code {
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
    font-size: 0.92rem;
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 1rem;
    overflow: auto;
    background: #faf9f7;
    color: var(--fg);
}

.page-header {
    margin-top: 2.5rem;
    margin-bottom: 1.5rem;
}

.page-header h1 {
    font-size: 2.2rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.page-header .subtitle {
    font-size: 1rem;
    color: #9a9a9a;
    margin: 0;
}

.card {
    border: 1px solid var(--line);
    background: var(--surface);
}

pre {
    margin: 0.4rem 0;
}

pre code {
    display: block;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
    font-size: 0.85rem;
    line-height: 1.45;
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 1rem;
    background: #faf9f7;
    color: var(--fg);
    overflow-x: auto;
    white-space: pre; /* garantit les sauts */
}

@media (max-width: 900px) {
    .hero-structured {
        flex-direction: column;
        gap: 2rem;
        padding-top: 4rem;
    }

    .logo-left {
        width: 160px;
    }

    .hero-text h1 {
        font-size: 2.4rem;
    }
}