/* Cornell RL Seminar — macOS-flavored, box-free course-page style */

:root {
  --text: #1d1d1f;          /* Apple near-black */
  --text-secondary: #6e6e73; /* Apple secondary gray */
  --link: #0066cc;           /* Apple link blue */
  --hairline: #d2d2d7;       /* Apple hairline gray */
  --bg: #ffffff;
  --accent-red: #ff5f57;     /* macOS traffic lights */
  --accent-yellow: #febc2e;
  --accent-green: #28c840;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body {
  font-family: Helvetica, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  line-height: 1.55;
}

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

a:hover {
  text-decoration: underline;
}

.page {
  max-width: 820px;
  margin: 0 auto;
  padding: 0 24px 96px;
}

/* ---------- Nav ---------- */

nav {
  display: flex;
  align-items: center;
  gap: 28px;
  padding: 20px 0;
  border-bottom: 1px solid var(--hairline);
  font-size: 14px;
  line-height: 1;
}

nav .branding {
  display: flex;
  align-items: center;
  gap: 10px;
}

nav .logo {
  height: 22px;
  width: auto;
}

nav .cornell-logo {
  height: 20px;
}

nav .brand-text {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1;
}

nav .links {
  margin-left: auto;
  display: flex;
  gap: 28px;
}

nav a {
  color: var(--text);
}

nav a:hover {
  color: var(--link);
  text-decoration: none;
}

nav a.active {
  color: var(--text-secondary);
  pointer-events: none;
}

/* ---------- Header ---------- */

header {
  padding: 64px 0 20px;
}

header h1 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.015em;
  line-height: 1.1;
}

header .course-info {
  font-size: 15px;
  color: var(--text-secondary);
  margin-top: 8px;
  margin-bottom: 20px;
  line-height: 1.5;
}

header .course-info a {
  color: var(--link);
}

header .subtitle {
  margin-top: 12px;
  font-size: 16px;
  color: var(--text-secondary);
}

/* ---------- Sections ---------- */

section {
  margin-top: 16px;
  margin-bottom: 16px;
}

section#news {
  margin-top: 48px;
}

section#schedule {
  margin-top: 48px;
}

section h2 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.01em;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--hairline);
}

section h2 .muted {
  font-weight: 400;
  color: var(--text-secondary);
  font-size: 19px;
}

/* ---------- News ---------- */

.news-list {
  list-style: none;
  margin-top: 8px;
}

.news-list li {
  display: flex;
  gap: 0;
  padding: 14px 0;
  border-bottom: 1px solid var(--hairline);
}

.news-list li:last-child {
  border-bottom: none;
}

.news-list .date {
  flex: 0 0 100px;
  padding-right: 12px;
  color: var(--text-secondary);
  font-size: 13px;
  padding-top: 2px;
}

/* ---------- Schedule ---------- */

.schedule {
  width: 100%;
  border-collapse: collapse;
  margin-top: 8px;
}

.schedule th {
  text-align: left;
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
  padding: 14px 16px 10px 0;
  border-bottom: 1px solid var(--hairline);
}

.schedule td {
  vertical-align: top;
  padding: 16px 16px 16px 0;
  border-bottom: 1px solid var(--hairline);
}

.schedule tr:last-child td {
  border-bottom: none;
}

.schedule .date {
  white-space: nowrap;
  color: var(--text-secondary);
  font-size: 13px;
  width: 100px;
  padding-right: 24px;
  padding-top: 18px;
}

.schedule .topic {
  font-weight: 600;
}

.schedule .paper {
  margin-top: 2px;
  font-size: 15px;
}

.schedule .presenter {
  white-space: nowrap;
  font-size: 15px;
  width: 130px;
}

.schedule .materials {
  white-space: nowrap;
  font-size: 15px;
  width: 90px;
}

.tbd {
  color: var(--text-secondary);
}

/* ---------- Syllabus page ---------- */

.prose h2 {
  margin-top: 56px;
}

.prose p,
.prose ul,
.prose ol {
  margin-top: 16px;
}

.prose ul,
.prose ol {
  padding-left: 24px;
}

.prose li {
  margin-top: 6px;
}

/* ---------- Footer ---------- */

footer {
  margin-top: 56px;
  padding-top: 20px;
  border-top: 1px solid var(--hairline);
  font-size: 14px;
  color: var(--text-secondary);
}

/* ---------- Small screens ---------- */

@media (max-width: 640px) {
  header h1 {
    font-size: 34px;
  }

  .news-list li {
    flex-direction: column;
    gap: 2px;
  }

  .schedule .presenter,
  .schedule th:nth-child(3) {
    display: none;
  }
}