:root {
  --radius: 0.625rem;
  --radius-lg: 1rem;
  --font-display: 'Syne', 'Noto Sans Arabic', system-ui, sans-serif;
  --font-body: 'IBM Plex Sans', 'Noto Sans Arabic', system-ui, sans-serif;
  --nav-h: 4.5rem;
  --max-w: 70rem;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --logo-filter: none;
}

/* Dark (default brand surface — matches Algorithm mark) */
html[data-theme='dark'] {
  --bg: oklch(0.12 0.01 260);
  --surface: oklch(0.16 0.012 260);
  --surface-2: oklch(0.2 0.014 260);
  --ink: oklch(0.96 0.005 260);
  --muted: oklch(0.7 0.015 260);
  --primary: oklch(0.68 0.14 260);
  --primary-hover: oklch(0.74 0.14 260);
  --accent: oklch(0.72 0.12 220);
  --border: oklch(1 0 0 / 0.1);
  --border-strong: oklch(1 0 0 / 0.16);
  --on-primary: oklch(0.12 0.01 260);
  --shadow: 0 1px 2px oklch(0 0 0 / 0.35), 0 16px 40px oklch(0 0 0 / 0.35);
  --nav-bg: oklch(0.12 0.01 260 / 0.82);
  --hero-grid: oklch(1 0 0 / 0.05);
  --glow: oklch(0.55 0.14 260 / 0.18);
  --card-hover: oklch(0.68 0.14 260 / 0.35);
  --logo-filter: none;
  color-scheme: dark;
}

html[data-theme='light'] {
  --bg: oklch(0.99 0.002 260);
  --surface: oklch(0.965 0.006 260);
  --surface-2: oklch(0.94 0.01 260);
  --ink: oklch(0.18 0.02 260);
  --muted: oklch(0.45 0.02 260);
  --primary: oklch(0.45 0.14 260);
  --primary-hover: oklch(0.38 0.14 260);
  --accent: oklch(0.48 0.12 220);
  --border: oklch(0.18 0.02 260 / 0.1);
  --border-strong: oklch(0.18 0.02 260 / 0.16);
  --on-primary: oklch(0.99 0 0);
  --shadow: 0 1px 2px oklch(0.18 0.02 260 / 0.05), 0 12px 32px oklch(0.18 0.02 260 / 0.08);
  --nav-bg: oklch(0.99 0.002 260 / 0.88);
  --hero-grid: oklch(0.18 0.02 260 / 0.06);
  --glow: oklch(0.5 0.14 260 / 0.12);
  --card-hover: oklch(0.45 0.14 260 / 0.28);
  /* --logo-filter: invert(1) hue-rotate(180deg); */
  color-scheme: light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  transition:
    background 0.25s var(--ease),
    color 0.25s var(--ease);
}

img {
  max-width: 100%;
  display: block;
}
a {
  color: inherit;
}
button,
input,
textarea {
  font: inherit;
}

.skip-link {
  position: absolute;
  inset-block-start: -100%;
  inset-inline-start: 1rem;
  z-index: 1000;
  padding: 0.5rem 1rem;
  background: var(--primary);
  color: var(--on-primary);
  border-radius: 0.5rem;
  text-decoration: none;
}
.skip-link:focus {
  inset-block-start: 1rem;
}

.container {
  width: min(100% - 2.5rem, var(--max-w));
  margin-inline: auto;
}

/* ── Nav ── */
.nav {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  z-index: 50;
  height: var(--nav-h);
  border-block-end: 1px solid transparent;
  transition:
    background 0.3s var(--ease),
    border-color 0.3s var(--ease),
    backdrop-filter 0.3s var(--ease);
}
.nav.is-scrolled {
  background: var(--nav-bg);
  backdrop-filter: blur(14px);
  border-color: var(--border);
}
.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: 1rem;
}
.nav__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  text-decoration: none;
  color: var(--ink);
}
.nav__brand-mark {
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 0.45rem;
  overflow: hidden;
  background: #000;
  flex-shrink: 0;
  border: 1px solid var(--border);
}
.nav__brand-mark img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: var(--logo-filter);
}
.nav__brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}
.nav__brand-text strong {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.92rem;
  letter-spacing: 0.08em;
}
.nav__brand-text span {
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
  font-weight: 500;
}
.nav__links {
  display: flex;
  align-items: center;
  gap: 0.15rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav__links a {
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--muted);
  padding: 0.45rem 0.7rem;
  border-radius: 0.45rem;
  transition:
    color 0.2s,
    background 0.2s;
}
.nav__links a:hover,
.nav__links a:focus-visible {
  color: var(--ink);
  background: var(--surface);
}
.nav__actions {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.icon-btn,
.lang-toggle {
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  overflow: hidden;
}
.lang-toggle button,
.icon-btn {
  border: none;
  background: transparent;
  padding: 0.4rem 0.65rem;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  color: var(--muted);
  transition:
    background 0.2s,
    color 0.2s;
}
.lang-toggle button[aria-pressed='true'] {
  background: var(--ink);
  color: var(--bg);
}
.icon-btn {
  width: 2.35rem;
  height: 2.35rem;
  padding: 0;
  justify-content: center;
  border-radius: 999px;
  color: var(--ink);
}
.icon-btn:hover {
  background: var(--surface-2);
}
.icon-btn:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}
.icon-btn svg {
  width: 1.05rem;
  height: 1.05rem;
}
.icon-btn .icon-sun {
  display: none;
}
html[data-theme='dark'] .icon-btn .icon-moon {
  display: none;
}
html[data-theme='dark'] .icon-btn .icon-sun {
  display: block;
}
html[data-theme='light'] .icon-btn .icon-moon {
  display: block;
}
html[data-theme='light'] .icon-btn .icon-sun {
  display: none;
}

.nav__menu-btn {
  display: none;
  border: 1px solid var(--border);
  background: var(--surface);
  border-radius: 0.5rem;
  width: 2.5rem;
  height: 2.5rem;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 0.28rem;
}
.nav__menu-btn span {
  display: block;
  width: 1.05rem;
  height: 2px;
  background: var(--ink);
  border-radius: 1px;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.35rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9rem;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition:
    transform 0.2s var(--ease),
    background 0.2s,
    box-shadow 0.2s,
    border-color 0.2s;
}
.btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}
.btn--primary {
  background: var(--primary);
  color: var(--on-primary);
  box-shadow: 0 6px 20px oklch(0.45 0.14 260 / 0.28);
}
.btn--primary:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
}
.btn--ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--border-strong);
}
.btn--ghost:hover {
  background: var(--surface);
}

/* ── Hero ── */
.hero {
  position: relative;
  padding-block: calc(var(--nav-h) + 5rem) 5.5rem;
  overflow: hidden;
}
.hero__grid {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(var(--hero-grid) 1px, transparent 1px), linear-gradient(90deg, var(--hero-grid) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 75% 65% at 50% 35%, black 15%, transparent 72%);
  pointer-events: none;
}
.hero__glow {
  position: absolute;
  inset-block-start: 10%;
  inset-inline-end: -8%;
  width: min(48vw, 32rem);
  height: min(48vw, 32rem);
  border-radius: 50%;
  background: radial-gradient(circle, var(--glow) 0%, transparent 68%);
  pointer-events: none;
  animation: pulse 10s ease-in-out infinite;
}
@keyframes pulse {
  0%,
  100% {
    transform: scale(1);
    opacity: 0.75;
  }
  50% {
    transform: scale(1.06);
    opacity: 1;
  }
}
.hero__layout {
  position: relative;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 3rem;
  align-items: center;
}
.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--primary);
  margin-block-end: 1.1rem;
}
.hero__eyebrow::before {
  content: '';
  width: 1.75rem;
  height: 1px;
  background: var(--primary);
}
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 5.5vw, 4rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin: 0 0 0.65rem;
  text-wrap: balance;
}
.hero__title {
  font-size: clamp(1.1rem, 2vw, 1.35rem);
  font-weight: 600;
  color: var(--ink);
  margin: 0 0 0.3rem;
}
.hero__alias {
  font-size: 0.95rem;
  color: var(--muted);
  margin: 0 0 1.35rem;
}
.hero__alias strong {
  color: var(--primary);
  font-weight: 600;
}
.hero__lead {
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 40ch;
  margin: 0 0 2rem;
  text-wrap: pretty;
}
.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}
.hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  margin-block-start: 3rem;
  padding-block-start: 1.75rem;
  border-block-start: 1px solid var(--border);
}
.hero__stat strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.55rem;
  font-weight: 800;
  color: var(--ink);
  line-height: 1.1;
}
.hero__stat span {
  font-size: 0.8rem;
  color: var(--muted);
}
.hero__mark {
  justify-self: center;
  width: min(100%, 22rem);
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  position: relative;
}
.hero__mark::before {
  content: '';
  position: absolute;
  inset: 8%;
  border-radius: 50%;
  border: 1px solid var(--border);
  opacity: 0.7;
}
.hero__mark::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 1px dashed var(--border);
  opacity: 0.45;
  animation: spin 48s linear infinite;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}
.hero__mark img {
  width: 72%;
  height: 72%;
  object-fit: contain;
  filter: var(--logo-filter);
  position: relative;
  z-index: 1;
  border-radius: 1rem;
  background: #000;
  padding: 8%;
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow);
}

/* ── Sections ── */
.section {
  padding-block: 5.25rem;
  scroll-margin-top: calc(var(--nav-h) + 0.75rem);
}
.section--surface {
  background: var(--surface);
}
.section__header {
  margin-block-end: 2.5rem;
  max-width: 36rem;
}
.section__label {
  display: block;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--primary);
  margin-block-end: 0.55rem;
}
.section h2 {
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.5vw, 2.35rem);
  font-weight: 800;
  letter-spacing: -0.025em;
  margin: 0 0 0.7rem;
  text-wrap: balance;
}
.section__desc {
  margin: 0;
  color: var(--muted);
  text-wrap: pretty;
}

/* ── Featured projects ── */
.featured {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}
.project-card {
  display: grid;
  grid-template-columns: 3.5rem 1fr auto;
  gap: 1.25rem;
  align-items: start;
  padding: 1.5rem 1.6rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  text-decoration: none;
  transition:
    border-color 0.25s,
    box-shadow 0.25s,
    transform 0.25s var(--ease),
    background 0.25s;
}
.section--surface .project-card {
  background: var(--bg);
}
.project-card:hover {
  border-color: var(--card-hover);
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}
.project-card__num {
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 0.06em;
  padding-block-start: 0.3rem;
}
.project-card__body h3 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  margin: 0 0 0.35rem;
  letter-spacing: -0.015em;
}
.project-card__body h3 span[lang='ar'] {
  font-weight: 600;
  color: var(--muted);
  font-size: 0.92em;
}
.project-card__body p {
  margin: 0 0 0.85rem;
  color: var(--muted);
  font-size: 0.92rem;
  max-width: 54ch;
}
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.tags li {
  font-size: 0.72rem;
  font-weight: 500;
  padding: 0.22rem 0.55rem;
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--muted);
  border: 1px solid var(--border);
}
.project-card__arrow {
  font-size: 1.15rem;
  color: var(--primary);
  padding-block-start: 0.2rem;
  transition: transform 0.25s var(--ease);
}
.project-card:hover .project-card__arrow {
  transform: translateX(4px);
}
[dir='rtl'] .project-card:hover .project-card__arrow {
  transform: translateX(-4px);
}

/* ── More work ── */
.work-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 0.85rem;
}
.work-item {
  padding: 1.25rem 1.3rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  transition:
    border-color 0.2s,
    transform 0.2s var(--ease),
    box-shadow 0.2s;
  min-height: 100%;
}
.work-item:hover {
  border-color: var(--card-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}
.work-item h3 {
  font-size: 1rem;
  font-weight: 600;
  margin: 0 0 0.35rem;
}
.work-item p {
  margin: 0;
  font-size: 0.86rem;
  color: var(--muted);
}

/* ── Security ── */
.security-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 0.85rem;
}
.security-card {
  padding: 1.4rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  transition:
    border-color 0.2s,
    transform 0.2s var(--ease),
    box-shadow 0.2s;
  position: relative;
  overflow: hidden;
}
.security-card::before {
  content: '';
  position: absolute;
  inset-block-start: 0;
  inset-inline: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), transparent);
  opacity: 0.7;
}
.security-card:hover {
  border-color: var(--card-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}
.security-card h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  margin: 0 0 0.45rem;
}
.security-card p {
  margin: 0;
  font-size: 0.88rem;
  color: var(--muted);
}
.security-card__link {
  display: inline-block;
  margin-block-start: 0.85rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--primary);
}

/* ── Skills ── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1.5rem;
}
.skill-group h3 {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 0.65rem;
}
.skill-group ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}
.skill-group li {
  font-size: 0.84rem;
  font-weight: 500;
  padding: 0.32rem 0.65rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 0.4rem;
  color: var(--ink);
}

/* ── Contact ── */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: start;
}
.contact-channels {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}
.contact-link {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding: 0.85rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  transition:
    border-color 0.2s,
    background 0.2s;
}
.contact-link:hover {
  border-color: var(--card-hover);
  background: var(--bg);
}
.contact-link__icon {
  width: 2.15rem;
  height: 2.15rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 0.45rem;
  font-size: 0.85rem;
  flex-shrink: 0;
  color: var(--primary);
  font-weight: 700;
}
.contact-link strong {
  display: block;
  font-size: 0.86rem;
  font-weight: 600;
}
.contact-link span {
  font-size: 0.8rem;
  color: var(--muted);
}
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  padding: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
}
.contact-form label {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.82rem;
  font-weight: 500;
}
.contact-form input,
.contact-form textarea {
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 0.45rem;
  background: var(--bg);
  color: var(--ink);
  transition: border-color 0.2s;
}
.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--primary);
}
.contact-form textarea {
  min-height: 7rem;
  resize: vertical;
}

/* ── Footer ── */
.footer {
  padding-block: 2rem;
  border-block-start: 1px solid var(--border);
}
.footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.82rem;
  color: var(--muted);
}
.footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
}
.footer__brand img {
  width: 1.5rem;
  height: 1.5rem;
  border-radius: 0.3rem;
  background: #000;
  filter: var(--logo-filter);
}
.footer__links {
  display: flex;
  gap: 1.15rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.footer__links a {
  text-decoration: none;
  color: var(--muted);
  transition: color 0.2s;
}
.footer__links a:hover {
  color: var(--ink);
}

/* ── Back to top ── */
.back-top {
  position: fixed;
  inset-block-end: 1.5rem;
  inset-inline-end: 1.5rem;
  z-index: 40;
  width: 3rem;
  height: 3rem;
  display: grid;
  place-items: center;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(0.75rem) scale(0.92);
  transition:
    opacity 0.28s var(--ease),
    transform 0.28s var(--ease),
    visibility 0.28s,
    background 0.2s,
    border-color 0.2s,
    color 0.2s;
}
.back-top.is-visible {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0) scale(1);
}
.back-top:hover {
  background: var(--primary);
  color: var(--on-primary);
  border-color: transparent;
}
.back-top:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}
.back-top svg {
  width: 1.15rem;
  height: 1.15rem;
}
@media (max-width: 768px) {
  .back-top {
    inset-block-end: 1.15rem;
    inset-inline-end: 1.15rem;
    width: 2.75rem;
    height: 2.75rem;
  }
}

/* ── Reveal ── */
.reveal {
  opacity: 1;
  transform: none;
}
@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(1rem);
    transition:
      opacity 0.55s var(--ease),
      transform 0.55s var(--ease);
  }
  .reveal.is-visible {
    opacity: 1;
    transform: none;
  }
}

@media (max-width: 900px) {
  .hero__layout {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  .hero__mark {
    order: -1;
    width: min(100%, 14rem);
  }
}
@media (max-width: 768px) {
  .nav__links {
    display: none;
  }
  .nav__links.is-open {
    display: flex;
    flex-direction: column;
    position: absolute;
    inset-block-start: var(--nav-h);
    inset-inline: 0;
    background: var(--bg);
    border-block-end: 1px solid var(--border);
    padding: 0.75rem 1rem 1rem;
    box-shadow: var(--shadow);
  }
  .nav__menu-btn {
    display: flex;
  }
  .nav__brand-text span {
    display: none;
  }
  .project-card {
    grid-template-columns: 1fr;
    gap: 0.4rem;
  }
  .project-card__arrow {
    display: none;
  }
  .contact-layout {
    grid-template-columns: 1fr;
  }
  .hero__stats {
    gap: 1.25rem;
  }
}