/* ===== VARIABLES ===== */
:root {
  --bg-color: #fdfdfd;
  --text-color: #2c2f33;
  --bg-container: #ffffff;
  --border-color: #eaeaea;
  --content-media-max: 760px;
  --accent-cyan: #39C5BB;
  --accent-hover: #2ba69d;
  --accent-fuchsia: #E12885;
  --table-header: #f4f7f6;
  --table-border: #e0e0e0;
  --blockquote-bg: #f5fcfc;
}

[data-theme="dark"] {
  --bg-color: #1a1b26;
  --text-color: #e0e0e0;
  --bg-container: #24283b;
  --border-color: #414868;
  --accent-cyan: #39C5BB;
  --accent-hover: #5ee0d6;
  --accent-fuchsia: #ff479f;
  --table-header: #1f2335;
  --table-border: #414868;
  --blockquote-bg: #1f2635;
}

/* ===== BASE ===== */
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
  line-height: 1.6;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
  background-color: var(--bg-container);
  padding: 30px 40px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

/* ===== HEADER ===== */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 2px solid var(--accent-cyan);
  padding-bottom: 10px;
  margin-bottom: 20px;
}

.btn-theme {
  background: none;
  border: 1px solid var(--accent-cyan);
  color: var(--text-color);
  padding: 5px 10px;
  border-radius: 4px;
  cursor: pointer;
}

/* ===== NAV ===== */
nav {
  margin: 20px 0;
  padding: 15px;
  background-color: var(--table-header);
  border-left: 4px solid var(--accent-cyan);
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
}

.nav-btn {
  padding: 8px 16px;
  background-color: var(--bg-container);
  color: var(--text-color) !important;
  border: 1px solid var(--accent-cyan);
  border-radius: 4px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s ease;
}

.nav-btn:hover {
  background-color: var(--accent-cyan);
  color: white !important;
}

/* ===== MEDIA ===== */
main img {
  display: block;
  width: 100%;
  max-width: min(100%, var(--content-media-max));
  height: auto;
  margin: 1.25rem auto;
}

/* ===== MATH RENDERING ===== */
.MathJax {
  overflow-x: auto;
  overflow-y: hidden;
}