/* ═══════════════════════════════════════════════════════
   BASE — reset, body, sidebar nav, section frame
   Theme-specific styles live in theme-*.css
   ═══════════════════════════════════════════════════════ */

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; overflow-x: hidden; }
body {
  font-family: 'Inter', system-ui, sans-serif;
  font-weight: 400;
  line-height: 1.6;
  overflow-x: hidden;
  background: #000;
}

/* ── Section frame ─────────────────────────────────── */
.section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  overflow: hidden;
}
.section__content {
  position: relative;
  z-index: 2;
  box-sizing: border-box;
  width: 100%;
  max-width: 900px;
  padding: 100px 60px 100px 260px;
}

/* ── Left-side nav ─────────────────────────────────── */
.nav {
  position: fixed;
  left: 0;
  top: 0;
  height: 100vh;
  width: 200px;
  z-index: 100;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 20px 0;
  /* color is theme-overridden */
  --nav-fg: rgba(255,255,255,0.7);
  --nav-fg-active: #fff;
  --nav-indicator: rgba(255,255,255,0.25);
  --nav-indicator-active: #fff;
  color: var(--nav-fg);
}
.nav__sections {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.nav__link {
  display: flex;
  align-items: center;
  text-decoration: none;
  color: var(--nav-fg);
  font-family: 'Inter', sans-serif;
  font-size: 16px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 10px 18px;
  transition: color 0.3s;
  white-space: nowrap;
}
.nav__link:hover, .nav__link.active { color: var(--nav-fg-active); }
.nav__indicator {
  display: inline-block;
  width: 3px;
  height: 16px;
  background: var(--nav-indicator);
  border-radius: 2px;
  margin-right: 12px;
  flex-shrink: 0;
  transition: background 0.3s, height 0.3s;
}
.nav__link.active .nav__indicator,
.nav__link:hover .nav__indicator {
  background: var(--nav-indicator-active);
  height: 24px;
}
/* drop-shadow under labels so they read against any theme bg */
.nav__link {
  text-shadow: 0 0 6px rgba(0,0,0,0.5), 0 0 12px rgba(0,0,0,0.3);
}

/* Mobile hamburger */
.nav__hamburger {
  display: none;
  position: fixed;
  top: 20px;
  left: 20px;
  z-index: 101;
  width: 40px;
  height: 40px;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 8px;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}
.nav__hamburger span {
  display: block;
  width: 20px;
  height: 2px;
  background: #fff;
  border-radius: 1px;
  transition: transform 0.3s, opacity 0.3s;
}
.nav__hamburger.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.nav__hamburger.open span:nth-child(2) { opacity: 0; }
.nav__hamburger.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ── Buttons ───────────────────────────────────────── */
.btn {
  display: inline-block;
  padding: 12px 28px;
  font-family: 'Inter', sans-serif;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  border: 1px solid currentColor;
  border-radius: 0;
  transition: background 0.25s, color 0.25s;
  cursor: pointer;
}

/* ── Responsive ────────────────────────────────────── */
@media (max-width: 900px) {
  .nav__hamburger { display: flex; }
  .nav {
    width: 100%;
    height: auto;
    background: rgba(0,0,0,0.85);
    backdrop-filter: blur(8px);
    transform: translateY(-100%);
    transition: transform 0.3s;
    padding: 60px 20px 20px;
    justify-content: flex-start;
  }
  .nav.open { transform: translateY(0); }
  /* Frame is inset 20px → padding pushes content off the frame border. */
  .section__content {
    padding: 100px 50px 100px 50px;
  }
}