/* Houssem Saidi | site stylesheet
   Fonts are self-hosted: no third-party requests, no cookies. */

@font-face { font-family: "Newsreader"; src: url("fonts/newsreader-opsz-normal.woff2") format("woff2"); font-weight: 200 800; font-style: normal; font-display: swap; }
@font-face { font-family: "Newsreader"; src: url("fonts/newsreader-opsz-italic.woff2") format("woff2"); font-weight: 200 800; font-style: italic; font-display: swap; }
@font-face { font-family: "IBM Plex Sans"; src: url("fonts/plex-sans-400.woff2") format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "IBM Plex Sans"; src: url("fonts/plex-sans-400-italic.woff2") format("woff2"); font-weight: 400; font-style: italic; font-display: swap; }
@font-face { font-family: "IBM Plex Sans"; src: url("fonts/plex-sans-500.woff2") format("woff2"); font-weight: 500; font-display: swap; }
@font-face { font-family: "IBM Plex Sans"; src: url("fonts/plex-sans-600.woff2") format("woff2"); font-weight: 600; font-display: swap; }
@font-face { font-family: "IBM Plex Mono"; src: url("fonts/plex-mono-400.woff2") format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "IBM Plex Mono"; src: url("fonts/plex-mono-500.woff2") format("woff2"); font-weight: 500; font-display: swap; }

:root {
  --paper: #f3f1ea;
  --paper-2: #eae7de;
  --ink: #15171a;
  --ink-2: #3a3e44;
  --muted: #676b71;
  --rule: #cbc6ba;
  --rule-strong: #15171a;
  --grid: rgba(21, 23, 26, 0.05);
  --accent: #c2410c;
  --accent-ink: #9a3412;
  --accent-soft: rgba(194, 65, 12, 0.10);
  --serif: "Newsreader", "Iowan Old Style", Georgia, serif;
  --sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --wrap: 1120px;
  --gutter: 28px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #111315;
    --paper-2: #181b1e;
    --ink: #ecebe6;
    --ink-2: #c8c7c1;
    --muted: #8f949a;
    --rule: #2e3237;
    --rule-strong: #ecebe6;
    --grid: rgba(236, 235, 230, 0.035);
    --accent: #f07a3a;
    --accent-ink: #f59a63;
    --accent-soft: rgba(240, 122, 58, 0.12);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #111315;
  --paper-2: #181b1e;
  --ink: #ecebe6;
  --ink-2: #c8c7c1;
  --muted: #8f949a;
  --rule: #2e3237;
  --rule-strong: #ecebe6;
  --grid: rgba(236, 235, 230, 0.035);
  --accent: #f07a3a;
  --accent-ink: #f59a63;
  --accent-soft: rgba(240, 122, 58, 0.12);
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 24px 24px;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--accent-ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 var(--gutter); }
.mono { font-family: var(--mono); font-size: 0.78rem; letter-spacing: 0.02em; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; background: var(--ink); color: var(--paper); padding: 8px 12px; z-index: 10; }

/* ---------- Top bar ---------- */
.topbar { border-bottom: 1px solid var(--rule); background: color-mix(in srgb, var(--paper) 88%, transparent); backdrop-filter: blur(6px); position: sticky; top: 0; z-index: 5; }
.topbar .wrap { display: flex; align-items: center; justify-content: space-between; height: 56px; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-family: var(--mono); font-size: 0.82rem; letter-spacing: 0.04em; }
.brand-mark { width: 12px; height: 12px; background: var(--accent); display: inline-block; }
.topnav { display: flex; align-items: center; gap: 22px; font-family: var(--mono); font-size: 0.78rem; }
.topnav a { text-decoration: none; color: var(--ink-2); }
.topnav a:hover { color: var(--accent-ink); }
.lang { border: 1px solid var(--rule); padding: 3px 8px; }
.lang[aria-current] { display: none; }

/* ---------- Hero ---------- */
.hero { padding: 72px 0 64px; border-bottom: 1px solid var(--rule); }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr); gap: 56px; align-items: end; }
.eyebrow { font-family: var(--mono); font-size: 0.76rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent-ink); margin: 0 0 22px; }
.hero h1 {
  font-family: var(--serif); font-weight: 380; font-optical-sizing: auto;
  font-size: clamp(3.1rem, 9vw, 7rem); line-height: 0.92; letter-spacing: -0.025em;
  margin: 0 0 32px;
}
.hero h1 span { display: block; }
.hero h1 em { font-style: italic; font-weight: 300; }
.lede { font-family: var(--serif); font-size: clamp(1.25rem, 2.2vw, 1.55rem); line-height: 1.4; margin: 0 0 18px; max-width: 34ch; color: var(--ink); font-weight: 400; }
.hero p.sub { color: var(--ink-2); max-width: 54ch; margin: 0 0 32px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-flex; align-items: center; gap: 10px; font-family: var(--mono); font-size: 0.8rem; letter-spacing: 0.03em; text-decoration: none; padding: 11px 16px; border: 1.5px solid var(--rule-strong); }
.btn-primary { background: var(--ink); color: var(--paper); }
.btn-primary:hover { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent-ink); }

/* Title block, as on an engineering drawing */
.titleblock { border: 1.5px solid var(--rule-strong); background: var(--paper); font-size: 0.9rem; }
.titleblock-head { display: flex; justify-content: space-between; align-items: center; padding: 10px 14px; border-bottom: 1.5px solid var(--rule-strong); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.06em; text-transform: uppercase; }
.titleblock dl { margin: 0; display: grid; grid-template-columns: auto 1fr; }
.titleblock dt, .titleblock dd { margin: 0; padding: 10px 14px; border-bottom: 1px solid var(--rule); }
.titleblock dt { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.05em; text-transform: uppercase; color: var(--muted); border-right: 1px solid var(--rule); padding-top: 12px; }
.titleblock dd { color: var(--ink); }
.titleblock dl > :nth-last-child(-n+2) { border-bottom: 0; }
.titleblock-foot { display: grid; grid-template-columns: 1fr 1fr 1fr; border-top: 1.5px solid var(--rule-strong); font-family: var(--mono); font-size: 0.68rem; letter-spacing: 0.04em; color: var(--muted); }
.titleblock-foot span { padding: 8px 14px; }
.titleblock-foot span + span { border-left: 1px solid var(--rule); }

/* ---------- Sections ---------- */
section.block { padding: 88px 0; border-bottom: 1px solid var(--rule); }
.sec-head { display: flex; align-items: center; gap: 14px; font-family: var(--mono); font-size: 0.76rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-bottom: 18px; }
.sec-head .num { color: var(--accent-ink); }
.sec-head::after { content: ""; flex: 1; height: 1px; background: var(--rule); }
h2 { font-family: var(--serif); font-weight: 400; font-size: clamp(2rem, 4.4vw, 3.1rem); line-height: 1.05; letter-spacing: -0.015em; margin: 0 0 20px; max-width: 22ch; }
.intro { color: var(--ink-2); max-width: 62ch; margin: 0 0 48px; }
h3 { font-family: var(--sans); font-weight: 600; font-size: 1.08rem; line-height: 1.3; margin: 0; }

/* ---------- Lifecycle chart ---------- */
.ladder { --stages: 6; }
.ladder-head, .work { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 2fr); column-gap: 40px; }
.ladder-head { border-bottom: 1.5px solid var(--rule-strong); padding-bottom: 12px; position: sticky; top: 56px; background: var(--paper); z-index: 2; }
.ladder-head .col-label { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); align-self: end; }
.stages { display: grid; grid-template-columns: repeat(var(--stages), 1fr); list-style: none; margin: 0; padding: 0; }
.stages li { font-family: var(--mono); font-size: 0.7rem; line-height: 1.25; color: var(--ink-2); text-align: center; padding: 0 4px; }
.stages li b { display: block; font-weight: 500; color: var(--muted); font-size: 0.66rem; margin-bottom: 3px; }
.legend { display: none; }

.work { padding: 30px 0 32px; border-bottom: 1px solid var(--rule); transition: background-color .2s; }
.work:hover { background: var(--accent-soft); }
.work-meta { display: flex; flex-direction: column; gap: 8px; padding-right: 8px; }
.work-meta .years { font-family: var(--mono); font-size: 0.74rem; color: var(--muted); }
.status { display: inline-flex; align-items: center; gap: 8px; font-family: var(--mono); font-size: 0.72rem; color: var(--accent-ink); letter-spacing: 0.02em; }
.status::before { content: ""; width: 8px; height: 8px; background: var(--accent); flex: none; }
.status.wip::before { background: transparent; border: 1.5px solid var(--accent); }
.work-body p { margin: 18px 0 0; color: var(--ink-2); max-width: 64ch; font-size: 0.98rem; }

.track { display: grid; grid-template-columns: repeat(var(--stages), 1fr); height: 22px; position: relative; }
.track::before { content: ""; position: absolute; left: 0; right: 0; top: 50%; height: 1px; background: var(--rule); }
.stop { position: relative; display: flex; align-items: center; justify-content: center; }
.stop::before, .stop::after { content: ""; position: absolute; top: calc(50% - 1.5px); height: 3px; width: 50%; background: var(--accent); transform: scaleX(0); transition: transform .45s cubic-bezier(.3,.7,.3,1); }
.stop::before { left: 0; transform-origin: left; }
.stop::after { right: 0; transform-origin: left; }
.stop.l::before, .stop.r::after { transform: scaleX(1); }
.stop.dash::before { background: repeating-linear-gradient(90deg, var(--accent) 0 5px, transparent 5px 9px); }
.stop i { position: relative; z-index: 1; width: 7px; height: 7px; background: var(--paper); border: 1px solid var(--rule); transform: rotate(45deg); }
.stop.on i { width: 13px; height: 13px; background: var(--accent); border: 0; transform: none; }
.stop.on.mid i { width: 9px; height: 9px; }
.stop.wip i { width: 13px; height: 13px; background: var(--paper); border: 2px solid var(--accent); transform: none; }

/* draw-in animation, only when JS is present and motion is welcome */
.js .ladder:not(.drawn) .stop::before, .js .ladder:not(.drawn) .stop::after { transform: scaleX(0); }
.js .ladder:not(.drawn) .stop.on i, .js .ladder:not(.drawn) .stop.wip i { opacity: 0; }
.stop i { transition: opacity .3s; }
@media (prefers-reduced-motion: reduce) { .stop::before, .stop::after, .stop i { transition: none !important; } }

.foot-note { font-family: var(--mono); font-size: 0.74rem; color: var(--muted); margin: 22px 0 0; max-width: 90ch; }

/* ---------- Leadership ---------- */
.lead-grid { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: 28px; }
.card { background: var(--paper); border: 1px solid var(--rule); padding: 28px; }
.card .tag { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); margin: 0 0 14px; }
.card p { color: var(--ink-2); margin: 12px 0 0; }
.c-roadmap { grid-column: span 5; }
.c-strategy { grid-column: span 7; grid-row: span 2; display: flex; flex-direction: column; }
.c-team { grid-column: span 5; }
.axes { list-style: none; margin: 18px 0 0; padding: 0; border-top: 1px solid var(--rule); }
.axes li { display: grid; grid-template-columns: 40px 1fr; padding: 9px 0; border-bottom: 1px solid var(--rule); font-size: 0.95rem; }
.axes li span { font-family: var(--mono); font-size: 0.72rem; color: var(--accent-ink); padding-top: 3px; }
.c-strategy h3 { font-family: var(--serif); font-weight: 400; font-size: 1.9rem; line-height: 1.1; letter-spacing: -0.01em; }
.schematic { margin: 26px 0 6px; color: var(--ink); }
.schematic svg { width: 100%; height: auto; display: block; }
.schematic figcaption { font-family: var(--mono); font-size: 0.7rem; color: var(--muted); margin-top: 8px; }
.stats { display: flex; gap: 28px; margin-top: 18px; flex-wrap: wrap; }
.stats div { display: flex; flex-direction: column; }
.stats b { font-family: var(--serif); font-weight: 400; font-size: 2.4rem; line-height: 1; }
.stats span { font-family: var(--mono); font-size: 0.7rem; color: var(--muted); margin-top: 6px; }

/* ---------- Research ---------- */
.research-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.25fr); gap: 56px; }
.thesis { border-left: 3px solid var(--accent); padding-left: 22px; }
.thesis .title { font-family: var(--serif); font-style: italic; font-size: 1.4rem; line-height: 1.3; margin: 0 0 14px; }
.thesis p { color: var(--ink-2); margin: 0 0 14px; }
.pubs { list-style: none; margin: 0; padding: 0; border-top: 1.5px solid var(--rule-strong); }
.pubs li { display: grid; grid-template-columns: 64px 1fr; gap: 16px; padding: 16px 0; border-bottom: 1px solid var(--rule); }
.pubs .yr { font-family: var(--mono); font-size: 0.8rem; color: var(--accent-ink); padding-top: 2px; }
.pubs a { text-decoration: none; font-weight: 500; line-height: 1.4; display: inline; }
.pubs a:hover { text-decoration: underline; }
.pubs .venue { display: block; font-family: var(--mono); font-size: 0.72rem; color: var(--muted); margin-top: 5px; }

/* ---------- Path ---------- */
.path { list-style: none; margin: 0; padding: 0; border-top: 1.5px solid var(--rule-strong); }
.path li { display: grid; grid-template-columns: 150px minmax(0, 1.2fr) minmax(0, 1fr); gap: 24px; padding: 16px 0; border-bottom: 1px solid var(--rule); align-items: baseline; }
.path .when { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); }
.path .what { font-weight: 500; }
.path .where { color: var(--ink-2); font-size: 0.95rem; }
.path li.edu .what::after { content: attr(data-kind); margin-left: 10px; font-family: var(--mono); font-size: 0.66rem; font-weight: 400; color: var(--muted); border: 1px solid var(--rule); padding: 1px 6px; vertical-align: 2px; }

/* ---------- Contact ---------- */
.contact { padding: 110px 0 120px; }
.contact h2 { max-width: 18ch; }
.mail { display: inline-block; font-family: var(--serif); font-size: clamp(1.7rem, 5.4vw, 3.6rem); line-height: 1.1; letter-spacing: -0.01em; text-decoration: none; border-bottom: 3px solid var(--accent); padding-bottom: 4px; margin: 18px 0 28px; overflow-wrap: anywhere; }
.mail:hover { color: var(--accent-ink); }
.contact .small { color: var(--muted); font-family: var(--mono); font-size: 0.76rem; }
.links { display: flex; gap: 18px; margin-top: 10px; font-family: var(--mono); font-size: 0.8rem; }

/* ---------- Footer ---------- */
footer { border-top: 1.5px solid var(--rule-strong); padding: 22px 0 40px; font-family: var(--mono); font-size: 0.72rem; color: var(--muted); }
footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
footer a { color: var(--muted); }

/* ---------- Legal page ---------- */
.legal { padding: 64px 0 96px; max-width: 760px; }
.legal h1 { font-family: var(--serif); font-weight: 400; font-size: clamp(2.2rem, 6vw, 3.4rem); margin: 0 0 32px; letter-spacing: -0.015em; }
.legal h2 { font-size: 1.4rem; margin: 36px 0 8px; }
.legal p { color: var(--ink-2); margin: 0 0 12px; }
.todo { background: var(--accent-soft); color: var(--accent-ink); font-family: var(--mono); font-size: 0.85em; padding: 1px 5px; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; gap: 44px; }
  .titleblock { max-width: 520px; }
  .c-roadmap, .c-team, .c-strategy { grid-column: span 12; grid-row: auto; }
  .research-grid { grid-template-columns: 1fr; gap: 40px; }
}
@media (max-width: 760px) {
  :root { --gutter: 16px; }
  body { font-size: 16px; }
  .topnav .hide-sm { display: none; }
  .hero { padding: 48px 0 48px; }
  section.block { padding: 64px 0; }
  .ladder-head { grid-template-columns: 1fr; position: static; padding-bottom: 0; border-bottom: 0; }
  .ladder-head .col-label { display: none; }
  .stages li { font-size: 0; padding: 0; }
  .stages li b { font-size: 0.66rem; margin: 0; }
  .legend { display: flex; flex-wrap: wrap; gap: 6px 14px; list-style: none; margin: 0 0 14px; padding: 0 0 12px; border-bottom: 1.5px solid var(--rule-strong); font-family: var(--mono); font-size: 0.7rem; color: var(--ink-2); }
  .legend b { color: var(--accent-ink); font-weight: 500; margin-right: 4px; }
  .work { grid-template-columns: 1fr; row-gap: 14px; padding: 24px 0; }
  .work-meta { flex-direction: row; flex-wrap: wrap; align-items: baseline; gap: 6px 14px; }
  .work-meta h3 { flex-basis: 100%; }
  .work-body p { margin-top: 14px; }
  .path li { grid-template-columns: 1fr; gap: 2px; }
  .card { padding: 22px; }
  .pubs li { grid-template-columns: 48px 1fr; gap: 12px; }
  .titleblock-foot { grid-template-columns: 1fr 1fr; }
  .titleblock-foot span:last-child { display: none; }
}
@media print {
  body { background: #fff; }
  .topbar, .actions { display: none; }
}