:root {
  --cornell-red: #B31B1B;
  --dark-bg: #111111;
  --panel: #1B1B1B;
  --panel-2: #222222;
  --text: #F7F7F7;
  --muted: #C9C9C9;
  --border: #333333;
  --link-blue: #6BB7D8;
  --white: #FFFFFF;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--dark-bg);
}

body {
  max-width: 1100px;
  margin: 0 auto;
  padding: 40px 24px;
  background: var(--dark-bg);
  color: var(--text);
  font-family: Inter, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.65;
  font-size: 16px;
}

header {
  background: var(--panel);
  border-top: 8px solid var(--cornell-red);
  padding: 36px;
  margin-bottom: 28px;
  border-radius: 0 0 12px 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

h1 {
  margin: 0 0 10px;
  font-size: clamp(2rem, 4vw, 2.65rem);
  font-weight: 750;
  letter-spacing: -0.04em;
  line-height: 1.1;
  color: var(--white);
}

h2 {
  margin: 0 0 14px;
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--white);
}

p {
  margin: 0 0 12px;
}

ul {
  margin-top: 8px;
}

.subtitle {
  margin: 0;
  max-width: 760px;
  font-size: 1.05rem;
  color: var(--muted);
}

.top-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  margin-bottom: 24px;
  font-size: 0.95rem;
}

.top-nav a {
  color: var(--link-blue);
  text-decoration: none;
  font-weight: 700;
}

.top-nav a:hover,
.top-nav a:focus {
  color: var(--white);
  text-decoration: underline;
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-left: 5px solid var(--cornell-red);
  border-radius: 12px;
  padding: 24px;
  margin: 20px 0;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.22);
}

.card:hover {
  background: var(--panel-2);
}

.terminal {
  margin: 20px 0;
  background: #050505;
  color: #7CFC8A;
  padding: 16px 18px;
  border-left: 5px solid var(--cornell-red);
  border-radius: 8px;
  font-family: "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 0.95rem;
  line-height: 1.55;
  overflow-x: auto;
  white-space: pre-wrap;
}

strong {
  font-weight: 700;
  color: var(--white);
}

a {
  color: var(--link-blue);
  text-decoration: none;
  font-weight: 700;
}

a:hover,
a:focus {
  color: var(--white);
  text-decoration: underline;
}

a:focus-visible {
  outline: 3px solid rgba(179, 27, 27, 0.65);
  outline-offset: 3px;
  border-radius: 4px;
}

footer {
  margin-top: 42px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 0.92rem;
  color: var(--muted);
}

code {
  font-family: "SFMono-Regular", Menlo, Consolas, monospace;
  background: #050505;
  color: var(--text);
  padding: 2px 5px;
  border-radius: 4px;
}

.floating-join {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: #050505;
  color: #7CFC8A;
  border-left: 4px solid var(--cornell-red);
  border-radius: 10px;
  padding: 14px 18px;
  font-family: "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 0.9rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 4px;
  max-width: 320px;
}

.floating-join strong {
  color: #7CFC8A;
  font-size: 0.95rem;
}

.card {
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.card:hover {
  transform: translateY(-3px);
  border-color: var(--cornell-red);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.35);
}

.terminal {
  position: relative;
  transition: box-shadow 0.18s ease, transform 0.18s ease;
}

.terminal:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 0 1px rgba(124, 252, 138, 0.22),
              0 0 22px rgba(124, 252, 138, 0.10);
}

.terminal::before {
  content: "$ ";
  color: var(--cornell-red);
  font-weight: 700;
}

.top-nav a {
  position: relative;
}

.top-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 0;
  height: 2px;
  background: var(--cornell-red);
  transition: width 0.18s ease;
}

.top-nav a:hover::after,
.top-nav a:focus::after {
  width: 100%;
}

a {
  transition: color 0.15s ease, text-shadow 0.15s ease;
}

a:hover,
a:focus {
  text-shadow: 0 0 12px rgba(107, 183, 216, 0.35);
}

@media (max-width: 700px) {
  body {
    padding: 24px 18px;
  }

  header {
    padding: 28px 22px;
  }

  .card {
    padding: 20px;
  }

  .terminal {
    font-size: 0.9rem;
  }
}