:root {
  --bg: #fefcf7;
  --text: #2a2a2a;
  --header-footer-bg: #fdf6e3;
  --header-footer-text: #2a2a2a;
  --link: #d97706;
  --link-hover: #92400e;
  --heading: #78350f;
  --brand: #d97706;   /* name color (Solarized amber) */
  --brand: #374151;
}
:root {
  --bg: #fefefe;          /* clean light background */
  --text: #1f2933;        /* dark slate for body text */
  --header-footer-bg: #e6f6f9; /* very pale teal wash */
  --header-footer-text: #0b667d; /* main teal */
  --link: #0b667d;        /* anchor link color */
  --link-hover: #084c5d;  /* darker teal hover */
  --heading: #0b667d;     /* headings in main teal */
  --brand: #374151;
}


body.dark {
  --bg: #1a1b26;
  --text: #c0caf5;
  --header-footer-bg: #24283b;
  --header-footer-text: #c0caf5;
  --link: #7aa2f7;
  --link-hover: #bb9af7;
  --heading: #bb9af7;
  --brand: #7dcfff;   /* name color (Tokyo Night cyan) */
}

/* ========== Shared Styles ========== */
body {
  margin: 0;
  font-family: system-ui, sans-serif;
  line-height: 1.5;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background-color: #ffffff !important;
  color: var(--text);
}

header, footer {
  padding: 1rem;
  background: var(--header-footer-bg);
  text-align: center;
  color: var(--header-footer-text);
}

footer {
  padding-top: 0;
}

nav {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

main {
  flex: 1;
  padding: 1rem;
  max-width: 70ch;       /* ~65–75 characters per line */
  margin: 0 auto;
  min-width: 640px;      /* desktop minimum */
  line-height: 1.6;      /* comfortable line spacing */
}

/* Paragraph spacing */
main p {
  margin: 1rem 0;        /* space between paragraphs */
}

/* On mobile, allow shrinking and add side padding */
@media (max-width: 640px) {
  main {
    min-width: auto;
    padding: 1rem 1.5rem;
  }
}

/* On very large screens, allow a bit more line length */
@media (min-width: 1200px) {
  main {
    max-width: 80ch;
  }
}
/* Paragraph spacing */
main p {
  margin: 1rem 0; /* full spacing for text blocks */
}

/* List styling */
main ul {
  margin: 0.75rem 0;   /* slightly less than paragraphs */
  padding-left: 1.25rem; /* indent bullets a bit */
}

main li {
  margin: 0.35rem 0;   /* tighter spacing between items */
  line-height: 1.5;    /* slightly denser than body text */
}
nav a {
  position: relative;
  text-decoration: none;
  color: var(--link);
  padding: 0.25rem 0;
  transition: color 0.2s ease; /* so the text color animates smoothly */
  user-select: none;
}

nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2px;
  background: var(--link-hover);
  opacity: 0;
  transition: opacity 0.2s ease;
}

nav a:hover {
  color: var(--link-hover); /* 👈 now the text itself changes color */
}

nav a:hover::after {
  opacity: 1;
}main a {
  text-decoration: none;
  color: var(--link);
  transition: color 0.2s ease;
}

main a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}


h1 {
  color: var(--brand);
}

h2, h3 {
  color: var(--heading);
  margin-top: 0;
}

/* Base layout */
header {
  position: relative;
  padding: 1rem;
  text-align: center;
}

/* Hamburger button */
.hamburger {
  position: fixed;
  top: 1rem;
  left: 1rem;
  background: var(--header-footer-bg);
  color: var(--text);
  border: none;
  font-size: 1.5rem;
  padding: 0.5rem 0.7rem;
  border-radius: 0.25rem;
  cursor: pointer;
  z-index: 1000;
}


ul li strong {
  font-weight: 600;
}

/* Theme toggle button */
.theme-toggle {
  position: fixed;
  top: 1rem;
  right: 1rem;
  background: var(--header-footer-bg);
  color: var(--text);
  border: none;
  border-radius: 50%;
  width: 2.5rem;
  height: 2.5rem;
  cursor: pointer;
  font-size: 1.2rem;
  z-index: 1000;
}

/* Nav styling */
nav {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 0.5rem;
}
section {
  opacity: 0;
  transform: translateY(10px);
  animation: fadeIn 0.5s ease forwards;
}
@keyframes fadeIn {
  to {
    opacity: 1;
    transform: none;
  }
}





/* Next Link*/
.next-link {
  margin-top: 2rem;
  text-align: right;
  margin-bottom: 0;
}

.next-link a {
  text-decoration: none;
  color: var(--link);
  transition: color 0.2s ease;
}

.next-link a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}


/* Mobile: hide nav until menu opens */
@media (max-width: 640px) {
  nav {
    display: none;
    flex-direction: column;
    background: var(--header-footer-bg);
    position: absolute;
    top: 3.5rem;
    left: 0;
    right: 0;
    padding: 1rem;
  }
  nav.open {
    display: flex;
  }
}