:root {
  --princeton-orange: #e77500;
  --text-dark: #222;
  --text-light: #555;
  --bg-light: #fafafa;
  --border-light: #ddd;
  --card-bg: #fff;
  --card-border: #eee;
  --faq-question-color: #2d1bb1;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Open Sans", Helvetica, Arial, sans-serif;
  font-size: 0.9rem; /* Size of the font in the body of the webpage. Default is 1.0rem */
  background-color: var(--bg-light);
  color: var(--text-dark);
  line-height: 1.3;
  /* subtle grid background */
  background-image: linear-gradient(to right, rgba(0,0,0,0.02) 1px, transparent 1px),
                    linear-gradient(to bottom, rgba(0,0,0,0.02) 1px, transparent 1px);
  background-size: 20px 20px;
}

header {
  border-bottom: 4px solid var(--princeton-orange);
  background: white;
}

.header-inner {
  max-width: 1000px;
  margin: 0 auto;
  padding: 1.2rem 1rem;
}

.course-title {
  font-family: "Merriweather", Georgia, serif;
  font-size: 1.8rem;
  margin: 0;
}

.course-meta {
  color: var(--text-light);
  font-size: 0.95rem;
}

.lecture-times {
  margin-top: 0.3rem;
  font-size: 0.95rem;
  color: var(--text-light);
}

nav {
  background: #fff;
  border-top: 1px solid var(--border-light);
}

.nav-inner {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0.5rem 1rem;
}

nav a {
  margin-right: 1.5rem;
  text-decoration: none;
  color: var(--text-dark);
  font-weight: 500;
}

nav a.active {
  font-weight: 600;
  color: var(--princeton-orange);
}

nav a:hover {
  color: var(--princeton-orange);
}

main {
  max-width: 1000px;
  margin: 2rem auto;
  padding: 0 1rem;
}

section {
  margin-bottom: 2.5rem;
}

section h2 {
  font-family: "Merriweather", serif;
  border-bottom: 2px solid var(--princeton-orange);
  padding-bottom: 0.3rem;
}

.symbol-divider {
  color: var(--text-light);
  margin: 0.5rem 0 1rem 0;
}

ul {
  padding-left: 1.2rem;
}

.tentative {
  color: var(--princeton-orange);
  font-weight: bold;
}

/* Format the fonts of the questions in F.A.Q */
.faq-questions {
  color: var(--faq-question-color);
  /* font-size: 1.0rem; */
}

footer {
  border-top: 1px solid var(--border-light);
  margin-top: 3rem;
  padding: 1rem;
  text-align: center;
  color: var(--text-light);
  font-size: 0.9rem;
}

/* Fade-in animation */
.fade-in-section {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in-section.is-visible {
  opacity: 1;
  transform: none;
}

/* Staff and Precept cards */
.staff-grid, .precepts-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.staff-card {
  background-color: var(--card-bg);
  border: 2px solid var(--card-border);
  padding: 0.8rem 1rem;
  border-radius: 6px;
  width: 240px;
  position: relative;
  cursor: default;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.precept-card {
  background-color: var(--card-bg);
  border: 2px solid var(--card-border);
  padding: 0.8rem 1rem;
  border-radius: 6px;
  width: 260px;
  position: relative;
  cursor: default;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.staff-card:hover, .precept-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

/* Hover info boxes */
.person-card {
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.5s ease, visibility 0.5s ease;
  position: absolute;
  top: 110%;
  left: 0;
  width: 260px;
  background-color: var(--card-bg);
  border: 1px solid var(--card-border);
  padding: 0.6rem;
  border-radius: 5px;
  font-size: 0.85rem;
  z-index: 10;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}


.staff-card:hover .person-card {
  opacity: 1;
  visibility: visible;
}


.precept-location {
  margin-top: 0.3rem;
  font-size: 0.85rem;
}

a {
  color: var(--princeton-orange);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* Assignment Conduct Table */
.assignment-conduct-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

.assignment-conduct-table th,
.assignment-conduct-table td {
/*  border: 1px solid var(--border-light); */
  border: 1px solid #ff8f00;         /* thinner Princeton orange border */
  padding: 0.6rem;
  vertical-align: top;
}

.assignment-conduct-table th {
/*  background: #f0f0f0; */
  background: #ff8f00;
  text-align: left;
}

.assignment-conduct-table td {
/*  background: var(--card-bg); */
  background: #fffaf0;
}

.assignment-conduct-table td:last-child {
  text-align: center;
  width: 70px;
}

/* Schedule Table */
.schedule-table {
  width: 120%;
  border-collapse: collapse;
  margin-top: 1rem;
}

.schedule-table th,
.schedule-table td {
/*  border: 1px solid var(--border-light); */
  border: 1px solid #ff8f00;         /* thinner Princeton orange border */
  padding: 0.6rem;
  vertical-align: top;
}

.schedule-table th {
/*  background: #f0f0f0; */
  background: #ff8f00;
  text-align: left;
}

.schedule-table td {
/*  background: var(--card-bg); */
  font-size: 0.8rem; /* Font size inside the table */
  background: #fffaf0;
}

.schedule-table td:last-child {
  text-align: left;
  width: 140px;
}

/* Assignment Comparison Table */
.assignment-comp-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

.assignment-comp-table th,
.assignment-comp-table td {
/*  border: 1px solid var(--border-light); */
  border: 1px solid #ff8f00;         /* thinner Princeton orange border */
  padding: 0.6rem;
  vertical-align: top;
}

.assignment-comp-table th {
/*  background: #f0f0f0; */
  background: #ff8f00;
  text-align: left;
}

.assignment-comp-table td {
/*  background: var(--card-bg); */
  font-size: 0.8rem; /* Font size inside the table */
  background: #fffaf0;
}

.assignment-comp-table td:last-child {
  text-align: left;
  width: 400px;
}

/* Math box */
.math-box {
  border: 1px solid #ff8f00;         /* thinner Princeton orange border */
  background-color: #fffaf0;         /* keep subtle cream */
  padding: 10px;                     /* reduce padding */
  margin: 15px 0;                     /* smaller vertical spacing */
  border-radius: 6px;                 /* slightly smaller radius */
  box-shadow: 1px 1px 5px rgba(0,0,0,0.08);  /* lighter shadow */
  width: 100%;
  display: inline-block;
}

.math-box-title {
  background-color: #ff8f00;         
  color: #000;
  font-weight: bold;
  padding: 4px 8px;                   /* smaller padding */
  border-top-left-radius: 6px;
  border-top-right-radius: 6px;
  font-size: 0.95em;                  /* slightly smaller */
  text-align: left;
}

.math-box-content {
  padding: 8px 8px;                    /* smaller padding */
  text-align: center;
  font-size: 0.95em;                   /* reduce font-size of math */
}


/* Styles for the <details> element when it is closed */
details {
  border: 1px solid #ccc;
  padding: 0.5em;
  border-radius: 4px;
}

/* Styles specifically for when the <details> element has the 'open' attribute */
details[open] {
  padding: 1em; /* Adjust padding when open */
  border-color: var(--princeton-orange); /* Change border color when open */
}