/* TracAhead site — clean white theme, no external deps. */
:root {
  --bg:        #ffffff;
  --bg-soft:   #f7f8fa;
  --bg-card:   #f1f3f6;
  --line:      #e2e5ea;
  --fg:        #1a1d23;
  --fg-dim:    #5f6878;
  --accent:    #2b7de9;
  --accent-2:  #ff7a2e;
  --good:      #22b573;
  --bad:       #e54d4d;
  --radius:    14px;
  --shadow:    0 1px 3px rgba(0,0,0,0.06), 0 6px 16px rgba(0,0,0,0.06);
  --font:      ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto,
               "Apple SD Gothic Neo", "Noto Sans KR", "Helvetica Neue",
               Arial, "Apple Color Emoji", "Segoe UI Emoji", sans-serif;
  --mono:      ui-monospace, SFMono-Regular, "JetBrains Mono", Menlo, Consolas, monospace;
}

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

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; display: block; }
hr { border: 0; border-top: 1px solid var(--line); margin: 2.5rem 0; }
code { font-family: var(--mono); background: var(--bg-card); padding: 0 0.4em; border-radius: 4px; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 10;
  background: rgba(255,255,255,0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.site-header-inner {
  max-width: 1100px; margin: 0 auto; padding: 0.6rem 1.25rem;
  display: flex; align-items: center; gap: 1.25rem;
}
.brand {
  display: flex; align-items: center; gap: 0.55rem;
  font-weight: 700; letter-spacing: 0.2px;
}
.brand-logo {
  height: 36px; width: auto; border-radius: 6px;
}
nav.main-nav { display: flex; gap: 1.1rem; margin-left: auto; }
nav.main-nav a {
  color: var(--fg-dim); font-size: 0.95rem; padding: 0.4rem 0.6rem; border-radius: 8px;
}
nav.main-nav a:hover, nav.main-nav a[aria-current="page"] {
  color: var(--fg); background: var(--bg-card); text-decoration: none;
}
.lang-toggle {
  display: inline-flex; align-items: center; gap: 0.4rem;
  background: var(--bg-card); border: 1px solid var(--line);
  border-radius: 999px; padding: 0.25rem 0.5rem;
  font-size: 0.85rem; color: var(--fg-dim);
  cursor: pointer; user-select: none;
}
.lang-toggle button {
  background: transparent; border: 0; color: inherit;
  padding: 0.2rem 0.55rem; border-radius: 999px; cursor: pointer; font: inherit;
}
.lang-toggle button[aria-pressed="true"] {
  background: var(--accent); color: #fff; font-weight: 600;
}

/* Main container */
main { max-width: 1100px; margin: 0 auto; padding: 2rem 1.25rem 4rem; }

section { margin: 2.25rem 0; }
h1, h2, h3 { line-height: 1.2; margin: 0 0 0.6rem; color: var(--fg); }
h1 { font-size: clamp(2rem, 4.5vw, 3.25rem); letter-spacing: -0.5px; }
h2 { font-size: clamp(1.4rem, 2.5vw, 1.9rem); }
h3 { font-size: 1.1rem; }
p  { margin: 0.5rem 0; color: var(--fg-dim); }
p.lead { font-size: 1.1rem; }

/* Hero */
.hero {
  display: grid; gap: 2rem; grid-template-columns: 1.1fr 1fr;
  align-items: center; margin-top: 1.5rem;
}
@media (max-width: 820px) { .hero { grid-template-columns: 1fr; } }

.eyebrow {
  display: inline-block; font-size: 0.75rem; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--accent);
  padding: 0.25rem 0.6rem; border: 1px solid rgba(43,125,233,0.3);
  border-radius: 999px; background: rgba(43,125,233,0.06);
}
.hero h1 { margin-top: 0.8rem; }
.hero p { color: var(--fg); opacity: 0.88; max-width: 36em; }
.hero-cta { display: flex; gap: 0.75rem; margin-top: 1.5rem; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.7rem 1.05rem; border-radius: 10px; font-weight: 600;
  border: 1px solid var(--line); background: var(--bg-card); color: var(--fg);
}
.btn:hover { text-decoration: none; background: #e8eaee; }
.btn-primary {
  background: linear-gradient(135deg, var(--accent), #5b9bf5);
  color: #fff; border-color: transparent;
}
.btn-primary:hover { filter: brightness(1.05); }

.video-wrap {
  position: relative; aspect-ratio: 16/9; border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
  background: #000; border: 1px solid var(--line);
}
.video-wrap iframe {
  position: absolute; inset: 0; width: 100%; height: 100%; border: 0;
}

/* Card grid */
.cards {
  display: grid; gap: 1rem; margin-top: 1.25rem;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}
.card {
  background: var(--bg-card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.1rem 1.15rem; box-shadow: var(--shadow);
}
.card h3 { color: var(--fg); margin-bottom: 0.4rem; }
.card p  { color: var(--fg-dim); font-size: 0.95rem; margin: 0; }

.bullets {
  list-style: none; padding: 0; margin: 1rem 0 0;
  display: grid; gap: 0.4rem;
}
.bullets li {
  position: relative; padding: 0.45rem 0 0.45rem 1.6rem; color: var(--fg-dim);
}
.bullets li::before {
  content: ""; position: absolute; left: 0; top: 0.85rem;
  width: 0.6rem; height: 0.6rem; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
}

/* Steps */
ol.steps {
  counter-reset: step; list-style: none; padding: 0;
  display: grid; gap: 0.7rem; margin: 1rem 0;
}
ol.steps li {
  counter-increment: step; position: relative; padding: 0.85rem 1rem 0.85rem 3.2rem;
  background: var(--bg-card); border: 1px solid var(--line);
  border-radius: var(--radius);
}
ol.steps li::before {
  content: counter(step); position: absolute; left: 0.9rem; top: 0.85rem;
  width: 1.6rem; height: 1.6rem; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; font-weight: 700; display: grid; place-items: center;
  font-size: 0.85rem;
}

.os-notes { display: grid; gap: 0.7rem; margin-top: 1rem; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.os-notes .card { padding: 0.85rem 1rem; }
.os-notes .card .label { color: var(--fg); font-weight: 600; margin-bottom: 0.25rem; }

/* FAQ */
.faq details {
  background: var(--bg-card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 0; margin: 0.6rem 0;
}
.faq details[open] { box-shadow: var(--shadow); }
.faq summary {
  cursor: pointer; list-style: none; padding: 0.9rem 1.1rem; font-weight: 600;
  display: flex; align-items: center; gap: 0.6rem;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; margin-left: auto; color: var(--fg-dim); font-size: 1.2rem;
  transition: transform 0.15s ease;
}
.faq details[open] summary::after { content: "\2212"; }
.faq .a { padding: 0 1.1rem 1rem; color: var(--fg-dim); }

/* Support */
.support .cta-row { display: flex; gap: 0.6rem; margin-top: 1rem; flex-wrap: wrap; }
.disclaimer {
  margin-top: 2rem; padding-top: 1.5rem; border-top: 1px solid var(--line);
  color: var(--fg-dim); font-size: 0.85rem;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--line); padding: 1.5rem 1.25rem;
  color: var(--fg-dim); font-size: 0.85rem; text-align: center;
}
.site-footer a { color: var(--fg-dim); }
.site-footer a:hover { color: var(--accent); }

/* Screenshot gallery (software page) */
.screenshots { display: flex; gap: 1.5rem; flex-wrap: wrap; margin: 2rem 0; }
.screenshots figure { flex: 1 1 540px; margin: 0; }
.screenshots img {
  width: 100%; border-radius: 8px; border: 1px solid var(--line);
  box-shadow: 0 2px 12px rgba(0,0,0,0.08);
}
.screenshots figcaption { text-align: center; margin-top: 0.6rem; font-size: 0.88rem; color: var(--fg-dim); }

/* Tiny utility */
.row { display: flex; gap: 0.6rem; flex-wrap: wrap; align-items: center; }
.badge {
  display: inline-block; font-size: 0.75rem; padding: 0.15rem 0.5rem;
  border-radius: 999px; background: var(--bg-card); border: 1px solid var(--line);
  color: var(--fg-dim);
}