/* Base */
:root { --bg: #0f1115; --panel: #ffffff; --ink: #222; --muted: #5e6672; --line: #e4e8ef; }
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: 'Montserrat', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  color: var(--ink);
  background: #f7f8fb;
}

/* 30% fixed sidebar (left) */
.history-sidebar {
  position: fixed;
  inset: 0 auto 0 0;        /* top, right, bottom, left */
  width: 30vw;              /* 30% of viewport width */
  min-width: 260px;         /* keep usable on large screens */
  max-width: 520px;         /* avoid being too wide on ultrawide */
  background: var(--bg);
  display: grid;
  place-items: center;
  padding: 2rem 1rem;
}

.history-sidebar .brand img {
  height: auto;
  display: block;
  filter: drop-shadow(0 6px 18px rgba(0,0,0,.35));
  user-select: none;
}

/* 70% scrollable content (right) */
.history-main {
  margin-left: 30vw;        /* make room for the fixed sidebar */
  padding: 3rem min(5vw, 48px);
  max-width: 1000px;        /* content line length */
}

.history-intro h1 {
  margin: 0 0 .35rem;
  font-size: clamp(1.6rem, 1.1rem + 1.6vw, 2.3rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}
.history-intro p {
  margin: 0 0 1.5rem;
  color: var(--muted);
}

/* Changelog cards */
.changelog { display: grid; gap: 1.25rem; }

.version {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1.25rem 1.25rem 1rem;
  box-shadow: 0 8px 24px rgba(0,0,0,.06);
}
.version h2 {
  margin: 0 0 .75rem;
  display: flex; align-items: baseline; gap: .75rem;
  font-size: 1.15rem; font-weight: 800;
}
.version .date { color: var(--muted); font-weight: 600; font-size: .9rem; }
.version ul { margin: 0; padding-left: 1.15rem; color: #3a4049; line-height: 1.55; }

/* Responsive: stack on mobile */
@media (max-width: 900px) {
  .history-sidebar {
    position: sticky;      /* becomes a top header strip */
    width: 100vw; min-width: 0; max-width: none;
    inset: 0 0 auto 0;
    padding: .75rem 1rem;
    place-items: start;
  }
  .history-sidebar .brand img { width: 160px; }
  .history-main { margin-left: 0; padding-top: 1.5rem; }
}