:root {
  --bg-start: #f5f7ff;
  --bg-end: #f6efe1;
  --text: #1b2430;
  --muted: #4f5b6d;
  --panel: rgba(255, 255, 255, 0.78);
  --line: #d6dcef;
  --accent: #ff8f2f;
  --accent-2: #1f7a8c;
  --shadow: rgba(20, 30, 58, 0.15);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  font-family: "Segoe UI", "Trebuchet MS", "DejaVu Sans", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top left, var(--bg-start), var(--bg-end) 60%, #ecf3e5 100%);
  min-height: 100%;
}

body {
  animation: fadeIn 0.4s ease;
}

.shell {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  width: 240px;
  padding: 1rem 1rem 1.5rem;
  background: linear-gradient(165deg, rgba(31, 122, 140, 0.96), rgba(31, 122, 140, 0.83));
  color: #e6fbff;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  transition: width 0.35s ease;
  position: sticky;
  top: 0;
  height: 100vh;
}

.sidebar nav {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.top-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem;
}

.sidebar a {
  color: #e6fbff;
  text-decoration: none;
  padding: 0.65rem 0.75rem;
  border-radius: 0.6rem;
  transition: background 0.25s ease, transform 0.25s ease;
}

.sidebar a:hover {
  background: rgba(255, 255, 255, 0.18);
  transform: translateX(4px);
}

.toggle {
  width: fit-content;
  border: 0;
  background: rgba(255, 255, 255, 0.18);
  color: white;
  padding: 0.45rem 0.75rem;
  border-radius: 0.6rem;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid rgba(255, 255, 255, 0.34);
  border-radius: 999px;
  overflow: hidden;
  margin-left: auto;
}

.lang-btn {
  border: 0;
  background: rgba(255, 255, 255, 0.08);
  color: #e6fbff;
  padding: 0.35rem 0.6rem;
  font: inherit;
  cursor: pointer;
  transition: background 0.2s ease;
}

.lang-btn.active {
  background: #e6fbff;
  color: var(--accent-2);
  font-weight: 700;
}

.lang-btn + .lang-btn {
  border-left: 1px solid rgba(255, 255, 255, 0.34);
}

.sidebar.collapsed {
  width: 68px;
}

.sidebar.collapsed a {
  overflow: hidden;
  white-space: nowrap;
}

.content {
  flex: 1;
  padding: 1.2rem;
  display: grid;
  gap: 1rem;
  max-width: 1080px;
}

.hero, .card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 1rem;
  padding: 1rem 1.2rem;
  box-shadow: 0 10px 30px var(--shadow);
  animation: slideUp 0.35s ease;
}

.hero {
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.84), rgba(255, 255, 255, 0.62));
}

.eyebrow { margin: 0; color: var(--accent-2); font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; }

h1, h2 {
  margin-top: 0.25rem;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
}

pre {
  margin: 0;
  padding: 0.8rem;
  background: #0f1726;
  color: #e6f6ff;
  border-radius: 0.7rem;
  overflow: auto;
}

code {
  font-family: "Consolas", "Courier New", monospace;
  font-size: 0.95rem;
}

.list-sample {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.muted { color: var(--muted); }

.card ul { padding-left: 1.2rem; }

a { color: var(--accent-2); font-weight: 600; }
a:hover { color: var(--accent); }

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from { transform: translateY(10px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

@media (max-width: 800px) {
  .shell { flex-direction: column; }
  .sidebar { width: 100%; height: auto; position: static; }
  .sidebar.collapsed { width: 100%; }
  .content { padding: 1rem 0.8rem 2rem; }
}