/* =========================================================================
   mohdahmer.com — personal site
   Single stylesheet, no framework. Sections in order:
   1. Tokens & theme   2. Reset   3. Layout   4. Header   5. Hero
   6. Sections         7. Cards   8. Timeline 9. Posts    10. Contact
   11. Footer          12. Animation   13. Responsive
   ========================================================================= */

/* ---- 1. Tokens & theme ------------------------------------------------- */
/* Light is the base. Dark is applied both by system preference (unless the
   user explicitly chose light) and by an explicit data-theme="dark". */

:root {
  --bg:          #ffffff;
  --bg-alt:      #f6f7f9;
  --bg-raised:   #ffffff;
  --text:        #14171f;
  --text-muted:  #5b6475;
  --text-faint:  #8a92a3;
  --border:      #e3e6ec;
  --border-soft: #eef0f4;
  --accent:      #2f6df6;
  --accent-soft: rgba(47, 109, 246, 0.10);
  --accent-text: #ffffff;
  --success:     #17915d;
  --danger:      #d13c3c;

  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.05);
  --shadow-md: 0 4px 16px rgba(16, 24, 40, 0.07);
  --shadow-lg: 0 18px 48px rgba(16, 24, 40, 0.11);

  --radius:    14px;
  --radius-sm: 9px;

  --wrap:   1120px;
  --gutter: clamp(1.25rem, 4vw, 2.5rem);

  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
          "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;

  /* Syntax colors for the hero code card — darkened for contrast on white. */
  --syn-key:  #a626a4;
  --syn-var:  #c1382c;
  --syn-prop: #1f6feb;
  --syn-str:  #2c7a3f;
  --syn-num:  #a3541a;

  --header-h: 68px;
  --ease: cubic-bezier(0.22, 0.68, 0.28, 1);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg:          #0d1117;
    --bg-alt:      #11161f;
    --bg-raised:   #151b25;
    --text:        #e8ebf1;
    --text-muted:  #9aa4b6;
    --text-faint:  #6d7787;
    --border:      #232b38;
    --border-soft: #1b222d;
    --accent:      #5b8cff;
    --accent-soft: rgba(91, 140, 255, 0.14);
    --accent-text: #0d1117;
    --success:     #3ecf8e;
    --danger:      #ff6b6b;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.55);

    --syn-key:  #c678dd;
    --syn-var:  #e06c75;
    --syn-prop: #61afef;
    --syn-str:  #98c379;
    --syn-num:  #d19a66;
  }
}

:root[data-theme="dark"] {
  --bg:          #0d1117;
  --bg-alt:      #11161f;
  --bg-raised:   #151b25;
  --text:        #e8ebf1;
  --text-muted:  #9aa4b6;
  --text-faint:  #6d7787;
  --border:      #232b38;
  --border-soft: #1b222d;
  --accent:      #5b8cff;
  --accent-soft: rgba(91, 140, 255, 0.14);
  --accent-text: #0d1117;
  --success:     #3ecf8e;
  --danger:      #ff6b6b;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.55);

  --syn-key:  #c678dd;
  --syn-var:  #e06c75;
  --syn-prop: #61afef;
  --syn-str:  #98c379;
  --syn-num:  #d19a66;
}

/* ---- 2. Reset ---------------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  margin: 0 0 0.5em;
  line-height: 1.15;
  letter-spacing: -0.021em;
  font-weight: 700;
}

h1 { font-size: clamp(2.3rem, 5.6vw, 3.9rem); letter-spacing: -0.03em; }
h2 { font-size: clamp(1.65rem, 3.4vw, 2.35rem); }
h3 { font-size: 1.12rem; }

p { margin: 0 0 1.1em; }
p:last-child { margin-bottom: 0; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

ul, ol { margin: 0; padding: 0; list-style: none; }

img, svg { max-width: 100%; }

/* Icons are drawn as strokes unless a shape opts into .filled. */
svg:not(.filled) {
  fill: none;
  stroke: currentColor;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
}
svg.filled { fill: currentColor; stroke: none; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  padding: 0.7rem 1.1rem;
  background: var(--accent);
  color: var(--accent-text);
  border-radius: 0 0 var(--radius-sm) 0;
  font-weight: 600;
}
.skip-link:focus { left: 0; }

/* ---- 3. Layout --------------------------------------------------------- */

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding: clamp(4rem, 9vw, 7rem) 0; }
.section-alt {
  background: var(--bg-alt);
  border-block: 1px solid var(--border-soft);
}

.section-label {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.section-intro {
  color: var(--text-muted);
  max-width: 58ch;
  margin-bottom: 2.75rem;
}

.link {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1.5px;
}

/* ---- 4. Header --------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(1.6) blur(12px);
  -webkit-backdrop-filter: saturate(1.6) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
}
.site-header.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text);
  font-weight: 700;
  letter-spacing: -0.015em;
}
.brand:hover { text-decoration: none; }

.brand-mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: var(--accent);
  color: var(--accent-text);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.nav ul {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.nav a {
  display: block;
  padding: 0.45rem 0.8rem;
  border-radius: 8px;
  color: var(--text-muted);
  font-size: 0.93rem;
  font-weight: 500;
  transition: color 0.18s, background-color 0.18s;
}
.nav a:hover { color: var(--text); background: var(--accent-soft); text-decoration: none; }
.nav a.active { color: var(--accent); background: var(--accent-soft); }

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex-shrink: 0; /* never let the toggles get squeezed off-screen */
}

.icon-btn {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-raised);
  color: var(--text-muted);
  cursor: pointer;
  transition: color 0.18s, border-color 0.18s, transform 0.18s var(--ease);
}
.icon-btn:hover { color: var(--accent); border-color: var(--accent); }
.icon-btn:active { transform: scale(0.94); }

.nav-toggle { display: none; }

/* Show the sun in dark mode (click → go light) and the moon in light mode. */
.icon-sun { display: none; }
.icon-moon { display: block; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .icon-sun  { display: block; }
  :root:not([data-theme="light"]) .icon-moon { display: none; }
}
:root[data-theme="dark"] .icon-sun  { display: block; }
:root[data-theme="dark"] .icon-moon { display: none; }
:root[data-theme="light"] .icon-sun  { display: none; }
:root[data-theme="light"] .icon-moon { display: block; }

/* ---- 5. Hero ----------------------------------------------------------- */

.hero {
  position: relative;
  padding: clamp(3.5rem, 8vw, 6.5rem) 0 clamp(3rem, 7vw, 5.5rem);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  top: -220px;
  right: -160px;
  width: 620px;
  height: 620px;
  background: radial-gradient(circle, var(--accent-soft), transparent 68%);
  pointer-events: none;
  z-index: -1;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: center;
}
/* Grid items default to min-width:auto, which lets the wide <pre> inside the
   code card stretch the column past the viewport. This pins them back. */
.hero-inner > * { min-width: 0; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.1rem;
  padding: 0.32rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-raised);
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--text-muted);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 0 0 color-mix(in srgb, var(--success) 60%, transparent);
  animation: pulse 2.4s infinite;
}
@keyframes pulse {
  70%  { box-shadow: 0 0 0 8px transparent; }
  100% { box-shadow: 0 0 0 0 transparent; }
}

.accent {
  color: var(--accent);
  background-image: linear-gradient(transparent 68%, var(--accent-soft) 0);
}

.lede {
  max-width: 52ch;
  margin-top: 1.1rem;
  font-size: clamp(1rem, 1.6vw, 1.13rem);
  color: var(--text-muted);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 1.9rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.72rem 1.4rem;
  border: 1px solid transparent;
  border-radius: 10px;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.18s var(--ease), box-shadow 0.2s, background-color 0.2s,
              border-color 0.2s, color 0.2s;
}
.btn:hover { text-decoration: none; transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn-primary {
  background: var(--accent);
  color: var(--accent-text);
  box-shadow: var(--shadow-md);
}
.btn-primary:hover { box-shadow: var(--shadow-lg); }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }

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

.social {
  display: flex;
  gap: 0.4rem;
  margin-top: 2.1rem;
}
.social a {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  color: var(--text-muted);
  transition: color 0.18s, background-color 0.18s, transform 0.18s var(--ease);
}
.social a:hover {
  color: var(--accent);
  background: var(--accent-soft);
  transform: translateY(-2px);
}

/* Code card */
.hero-card {
  min-width: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-raised);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.card-bar {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.7rem 0.95rem;
  border-bottom: 1px solid var(--border-soft);
  background: var(--bg-alt);
}
.card-bar span {
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--border);
}
.card-bar span:nth-child(1) { background: #ff5f57; }
.card-bar span:nth-child(2) { background: #febc2e; }
.card-bar span:nth-child(3) { background: #28c840; }
.card-bar em {
  margin-left: auto;
  font-family: var(--mono);
  font-style: normal;
  font-size: 0.76rem;
  color: var(--text-faint);
}

.code {
  max-width: 100%;
  margin: 0;
  padding: 1.35rem 1.4rem;
  font-family: var(--mono);
  font-size: clamp(0.72rem, 2.4vw, 0.845rem);
  line-height: 1.75;
  color: var(--text);
  overflow-x: auto;
}
.c-key  { color: var(--syn-key); }
.c-var  { color: var(--syn-var); }
.c-prop { color: var(--syn-prop); }
.c-str  { color: var(--syn-str); }
.c-num  { color: var(--syn-num); }
.c-fn   { color: var(--syn-prop); }
.c-com  { color: var(--text-faint); font-style: italic; }

/* ---- 6. About ---------------------------------------------------------- */

.about-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: clamp(2rem, 5vw, 3.5rem);
  align-items: start;
}
.about-grid > * { min-width: 0; }
.about-grid p { color: var(--text-muted); }

.stack-title {
  margin-top: 2rem;
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.chips li {
  padding: 0.36rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-raised);
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color 0.18s, border-color 0.18s, transform 0.18s var(--ease);
}
.chips li:hover {
  color: var(--accent);
  border-color: var(--accent);
  transform: translateY(-2px);
}

.stats { display: grid; gap: 0.9rem; }
.stat {
  padding: 1.2rem 1.3rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-raised);
  box-shadow: var(--shadow-sm);
}
.stat strong {
  display: block;
  font-size: 1.9rem;
  line-height: 1.1;
  letter-spacing: -0.03em;
  color: var(--accent);
}
.stat span {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* ---- 7. Project cards -------------------------------------------------- */

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}

.card {
  display: flex;
  flex-direction: column;
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-raised);
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s var(--ease), box-shadow 0.25s, border-color 0.25s;
}
.card:hover {
  transform: translateY(-4px);
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
  box-shadow: var(--shadow-lg);
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.1rem;
}
.card-icon { color: var(--accent); }

.card-links {
  display: flex;
  gap: 0.85rem;
  font-size: 0.85rem;
  font-weight: 600;
}
.card-links a { color: var(--text-faint); }
.card-links a:hover { color: var(--accent); text-decoration: none; }

.card p {
  flex: 1;
  font-size: 0.94rem;
  color: var(--text-muted);
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 1.1rem;
}
.tags li {
  padding: 0.22rem 0.6rem;
  border-radius: 6px;
  background: var(--accent-soft);
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--accent);
}

/* ---- 8. Timeline ------------------------------------------------------- */

.timeline {
  position: relative;
  margin-top: 2.5rem;
  padding-left: 1.6rem;
  border-left: 2px solid var(--border);
}
.timeline > li {
  position: relative;
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 1.5rem;
  padding-bottom: 2.5rem;
}
.timeline > li > * { min-width: 0; }
.timeline > li:last-child { padding-bottom: 0; }
.timeline > li::before {
  content: "";
  position: absolute;
  left: calc(-1.6rem - 7px);
  top: 0.55rem;
  width: 12px;
  height: 12px;
  border: 2px solid var(--accent);
  border-radius: 50%;
  background: var(--bg);
}

.tl-meta {
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--text-faint);
  padding-top: 0.15rem;
}
.tl-body p { color: var(--text-muted); font-size: 0.95rem; }
.tl-body h3 { font-size: 1.06rem; }
.at { color: var(--text-faint); }
.org { color: var(--accent); }

.cv-line {
  margin-top: 2.5rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* ---- 9. Posts ---------------------------------------------------------- */

.posts { display: grid; gap: 0.75rem; }
.posts a {
  display: block;
  padding: 1.35rem 1.5rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-raised);
  color: inherit;
  transition: transform 0.22s var(--ease), border-color 0.22s, box-shadow 0.22s;
}
.posts a:hover {
  transform: translateX(5px);
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
  box-shadow: var(--shadow-md);
  text-decoration: none;
}
.posts time {
  display: block;
  margin-bottom: 0.35rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--text-faint);
}
.posts h3 { margin-bottom: 0.3rem; }
.posts a:hover h3 { color: var(--accent); }
.posts p { font-size: 0.93rem; color: var(--text-muted); }

/* ---- 10. Contact ------------------------------------------------------- */

.contact-wrap { max-width: 720px; }

.contact-form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.1rem;
}
.field { display: flex; flex-direction: column; }
.field-full { grid-column: 1 / -1; }

.field label {
  margin-bottom: 0.4rem;
  font-size: 0.87rem;
  font-weight: 600;
}

.field input,
.field textarea {
  padding: 0.75rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-raised);
  color: var(--text);
  font: inherit;
  font-size: 0.95rem;
  transition: border-color 0.18s, box-shadow 0.18s;
}
.field textarea { resize: vertical; min-height: 120px; }
.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.field.invalid input,
.field.invalid textarea { border-color: var(--danger); }

.error {
  min-height: 1.1rem;
  margin: 0.3rem 0 0;
  font-size: 0.8rem;
  color: var(--danger);
}

.hp { position: absolute; left: -9999px; opacity: 0; }

.form-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
}
.form-status { margin: 0; font-size: 0.9rem; color: var(--text-muted); }
.form-status.ok    { color: var(--success); }
.form-status.error { color: var(--danger); }

.contact-alt {
  margin-top: 2rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* ---- 11. Footer -------------------------------------------------------- */

.site-footer {
  padding: 2rem 0;
  border-top: 1px solid var(--border-soft);
  background: var(--bg-alt);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.88rem;
  color: var(--text-muted);
}
.to-top { color: var(--text-muted); font-weight: 500; }
.to-top:hover { color: var(--accent); text-decoration: none; }

/* ---- 12. Scroll reveal ------------------------------------------------- */

/* Elements only start hidden when JS is available to reveal them again —
   .js is set by the inline script in <head>. */
.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}
.js .reveal.visible { opacity: 1; transform: none; }

@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;
  }
  .js .reveal { opacity: 1; transform: none; }
}

/* ---- 13. Responsive ---------------------------------------------------- */

@media (max-width: 900px) {
  .hero-inner,
  .about-grid { grid-template-columns: 1fr; }

  .stats { grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); }

  .timeline > li { grid-template-columns: 1fr; gap: 0.5rem; }
}

@media (max-width: 760px) {
  .nav-toggle { display: grid; }

  .nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    display: none;
    padding: 0.75rem var(--gutter) 1.25rem;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
  }
  .nav.open { display: block; }
  .nav ul { flex-direction: column; align-items: stretch; gap: 0.15rem; }
  .nav a { padding: 0.7rem 0.8rem; font-size: 1rem; }

  .brand-name { display: none; }

  .contact-form { grid-template-columns: 1fr; }

  .footer-inner { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 400px) {
  .hero-actions .btn { width: 100%; }
}

/* ---- Print (résumé-friendly) ------------------------------------------- */

@media print {
  .site-header, .hero-card, .social, .hero-actions,
  .contact-form, .to-top, .skip-link { display: none !important; }
  body { color: #000; background: #fff; }
  .js .reveal { opacity: 1; transform: none; }
  .section { padding: 1.5rem 0; }
}