/* ===========================================================================
   Denis Baldakov — portfolio styles
   Single shared stylesheet for every page. Edit colours/spacing in :root.
   =========================================================================== */

:root {
  --bg:        #ffffff;
  --surface:   #fafafa;
  --border:    #e4e4e7;
  --text:      #18181b;
  --muted:     #52525b;
  --accent:    #2557d6;
  --accent-2:  #1a3fa0;
  --maxw:      960px;
  --radius:    12px;
  --font: "Helvetica Neue", Arial, system-ui, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg:      #0d0d10;
    --surface: #16161b;
    --border:  #2a2a31;
    --text:    #ececee;
    --muted:   #a1a1aa;
    --accent:  #6a9bff;
    --accent-2:#9cbcff;
  }
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---- Navigation ---------------------------------------------------------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav .container {
  display: flex; align-items: center; justify-content: space-between;
  height: 60px;
}
.nav .brand { font-weight: 700; font-size: 1.05rem; letter-spacing: -0.01em; color: var(--text); }
.nav .links { display: flex; gap: 22px; }
.nav .links a { color: var(--muted); font-size: 0.95rem; font-weight: 500; }
.nav .links a:hover { color: var(--text); text-decoration: none; }
.nav .links a.active { color: var(--text); }
.nav .links a.active::after {
  content: ""; display: block; height: 2px; background: var(--accent);
  border-radius: 2px; margin-top: 3px;
}

/* ---- Section headers (CV-consistent: caps + rule) ------------------------ */
.section { padding: 54px 0; }
.section h2 {
  font-size: 0.82rem; text-transform: uppercase; letter-spacing: 0.14em;
  color: var(--muted); font-weight: 700;
  border-bottom: 1px solid var(--border); padding-bottom: 10px; margin-bottom: 26px;
}

/* ---- Hero ---------------------------------------------------------------- */
.hero { padding: 72px 0 40px; }
.hero h1 { font-size: 2.7rem; font-weight: 800; letter-spacing: -0.03em; line-height: 1.1; }
.hero .role { font-size: 1.2rem; color: var(--accent); font-weight: 600; margin-top: 6px; }
.hero p.lead { font-size: 1.1rem; color: var(--muted); max-width: 620px; margin-top: 18px; }
.hero .actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }

/* ---- Buttons ------------------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 18px; border-radius: 999px; font-weight: 600; font-size: 0.95rem;
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  transition: transform .12s ease, border-color .12s ease, background .12s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); border-color: var(--accent); }
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn.primary:hover { background: var(--accent-2); border-color: var(--accent-2); }

/* ---- Stat row ------------------------------------------------------------ */
.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 8px; }
.stat { border: 1px solid var(--border); border-radius: var(--radius); padding: 18px 20px; background: var(--surface); }
.stat .n { font-size: 1.5rem; font-weight: 800; letter-spacing: -0.02em; }
.stat .l { color: var(--muted); font-size: 0.9rem; margin-top: 2px; }

/* ---- Cards (projects / papers) ------------------------------------------- */
.grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.card {
  border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--surface); padding: 22px; display: flex; flex-direction: column;
  transition: transform .14s ease, border-color .14s ease, box-shadow .14s ease;
}
.card:hover { transform: translateY(-3px); border-color: var(--accent); box-shadow: 0 8px 30px rgba(0,0,0,.06); }
.card .tag { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.1em; color: var(--accent); font-weight: 700; }
.card h3 { font-size: 1.2rem; margin: 8px 0 6px; letter-spacing: -0.01em; }
.card p { color: var(--muted); font-size: 0.96rem; flex: 1; }
.card .tech { display: flex; flex-wrap: wrap; gap: 6px; margin: 14px 0 4px; }
.card .tech span {
  font-size: 0.75rem; color: var(--muted); border: 1px solid var(--border);
  border-radius: 6px; padding: 2px 8px; background: var(--bg);
}
.card .card-links { display: flex; gap: 14px; margin-top: 16px; font-size: 0.9rem; font-weight: 600; }
.card .card-links a::before { content: "→ "; color: var(--muted); }

/* ---- Featured media (video / report) ------------------------------------- */
.media { border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: #000; }
.media video { width: 100%; display: block; }
.embed-pdf { width: 100%; height: 80vh; border: 1px solid var(--border); border-radius: var(--radius); }

/* ---- Journey (scaffold for the future animated world map) ---------------- */
#journey .map-slot {
  position: relative; border: 1px dashed var(--border); border-radius: var(--radius);
  background: var(--surface); min-height: 120px; margin-bottom: 26px;
  display: flex; align-items: center; justify-content: center; color: var(--muted);
  font-size: 0.9rem; text-align: center; padding: 20px;
}
/* --- animated world map (JS-enhanced; falls back to the dashed slot) ------- */
#world-map.wm {
  border: 1px solid #1b1b22;
  border-radius: var(--radius);
  background: radial-gradient(125% 150% at 50% 4%, #16161d 0%, #0b0b0f 55%, #060608 100%);
  padding: 0; min-height: 0; overflow: hidden; display: block;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.03);
}
.wm-svg { width: 100%; height: auto; display: block; opacity: 0; transition: opacity .8s ease; }
.wm-svg.in { opacity: 1; }

/* land: white silhouette on the dark panel */
.wm-land path {
  fill: #eceef3; fill-opacity: .92;
  stroke: #0a0a0c; stroke-width: .5; vector-effect: non-scaling-stroke;
}

/* markers */
.wm-markers { filter: drop-shadow(0 0 4px color-mix(in srgb, var(--accent) 70%, transparent)); }
.wm-pin .wm-dot {
  fill: #ffffff; stroke: var(--accent); stroke-width: 2;
  opacity: 0; transform: scale(0);
  transform-box: fill-box; transform-origin: center;
}
.wm-svg.in .wm-pin .wm-dot {
  animation: wm-pop .5s cubic-bezier(.2,1.3,.4,1) forwards;
  animation-delay: calc(.5s + var(--i) * .35s);
}
@keyframes wm-pop { to { opacity: 1; transform: scale(1); } }

.wm-pin .wm-ping {
  fill: none; stroke: var(--accent); stroke-width: 1.5; opacity: 0;
  transform-box: fill-box; transform-origin: center;
}
.wm-svg.in .wm-pin .wm-ping {
  animation: wm-ping 2.6s ease-out infinite;
  animation-delay: calc(1s + var(--i) * .35s);
}
@keyframes wm-ping {
  0%   { opacity: .5;  transform: scale(.4); }
  70%  { opacity: 0;   transform: scale(3.4); }
  100% { opacity: 0;   transform: scale(3.4); }
}

/* flight-path arcs (draw-on; delay set inline per arc in worldmap.js) */
.wm-arc {
  fill: none; stroke: var(--accent); stroke-width: 1.8; stroke-linecap: round;
  vector-effect: non-scaling-stroke; opacity: .9;
  filter: drop-shadow(0 0 3px color-mix(in srgb, var(--accent) 60%, transparent));
}
.wm-svg.in .wm-arc { animation: wm-draw 1s ease forwards; }
@keyframes wm-draw { to { stroke-dashoffset: 0; } }

/* labels */
.wm-label { opacity: 0; }
.wm-svg.in .wm-label { animation: wm-fade .6s ease forwards; animation-delay: calc(.75s + var(--i) * .35s); }
@keyframes wm-fade { to { opacity: 1; } }
.wm-label text {
  font-family: var(--font);
  paint-order: stroke; stroke: #060608; stroke-width: 3px; stroke-linejoin: round;
  vector-effect: non-scaling-stroke;
}
.wm-city { fill: #f4f5f8; font-size: 15px; font-weight: 700; }
.wm-meta { fill: #aeb4c0; font-size: 12px; }

@media (prefers-reduced-motion: reduce) {
  .wm-svg, .wm-svg.in .wm-pin .wm-dot, .wm-svg.in .wm-pin .wm-ping,
  .wm-svg.in .wm-arc, .wm-svg.in .wm-label { animation: none !important; transition: none !important; opacity: 1 !important; }
  .wm-svg.in .wm-pin .wm-dot { transform: scale(1); }
  .wm-svg.in .wm-arc { stroke-dashoffset: 0 !important; }
}
@media (max-width: 720px) {
  .wm-city { font-size: 20px; }
  .wm-meta { font-size: 16px; }
}

.timeline { position: relative; padding-left: 26px; }
.timeline::before { content: ""; position: absolute; left: 7px; top: 4px; bottom: 4px; width: 2px; background: var(--border); }
.tl-item { position: relative; padding: 0 0 22px 4px; opacity: 0; transform: translateY(10px); }
.tl-item.in { opacity: 1; transform: none; transition: opacity .5s ease, transform .5s ease; }
.tl-item::before {
  content: ""; position: absolute; left: -23px; top: 6px; width: 12px; height: 12px;
  border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 22%, transparent);
}
.tl-item .when { font-size: 0.8rem; color: var(--muted); }
.tl-item .what { font-weight: 700; margin-top: 1px; }
.tl-item .where { color: var(--muted); font-size: 0.92rem; }

/* ---- Footer -------------------------------------------------------------- */
.footer { border-top: 1px solid var(--border); margin-top: 40px; padding: 34px 0; color: var(--muted); font-size: 0.92rem; }
.footer .container { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; }
.footer a { color: var(--muted); }
.footer a:hover { color: var(--text); }

/* ---- Prose (research write-ups) ------------------------------------------ */
.prose p { color: var(--muted); margin-bottom: 14px; max-width: 680px; }
.prose ul { color: var(--muted); margin: 0 0 16px 22px; }
.prose li { margin-bottom: 6px; }

/* ---- Responsive ---------------------------------------------------------- */
@media (max-width: 720px) {
  .hero h1 { font-size: 2.1rem; }
  .grid, .stats { grid-template-columns: 1fr; }
  .nav .links { gap: 16px; }
  .nav .brand { font-size: 0.98rem; }
}