:root {
  --bg: #fdfdfd;
  --surface: #ffffff;
  --ink: #1a1a1a;
  --accent-blue: #0b81a2;
  --accent-purple: #7E4794;
  --accent-teal: #59a89c;
  --accent-amber: #f0c571;
  --accent-pink: #e25759;
  --border-width: 3px;
  --shadow: 8px 8px 0px 0px var(--ink);
}

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

body {
  background: var(--bg);
  color: var(--ink);
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
  padding: 2rem;
  background-image: radial-gradient(var(--ink) 0.5px, transparent 0.5px);
  background-size: 20px 20px;
}

.container {
  max-width: 900px;
  margin: 0 auto;
}

header {
  background: var(--surface);
  border: var(--border-width) solid var(--ink);
  padding: 2.5rem;
  border-radius: 25px;
  box-shadow: var(--shadow);
  margin-bottom: 3rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.back-btn {
  position: absolute;
  top: 1rem;
  left: 1rem;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  padding: 0.5rem 1rem;
  border-radius: 10px;
  font-family: 'Lexend';
  font-weight: 800;
  font-size: 0.8rem;
  transition: 0.2s;
}

.back-btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 2px 2px 0px var(--accent-blue);
}

h1 {
  font-family: 'Lexend', sans-serif;
  font-size: 2.2rem;
  text-transform: uppercase;
  margin-bottom: 1rem;
  line-height: 1.1;
}

.intro-text {
  font-size: 1.1rem;
  font-weight: 500;
  opacity: 0.8;
  max-width: 700px;
  margin: 0 auto;
}

h2 {
  font-family: 'Lexend';
  font-size: 1.6rem;
  background: var(--accent-purple);
  color: #fff;
  display: inline-block;
  padding: 0.5rem 1.5rem;
  border: var(--border-width) solid var(--ink);
  border-radius: 12px;
  margin: 3rem 0 1.5rem;
  box-shadow: 4px 4px 0px var(--ink);
  text-transform: uppercase;
}

h3 {
  font-family: 'Lexend';
  font-size: 1.3rem;
  margin: 2rem 0 1rem;
  border-left: 5px solid var(--accent-blue);
  padding-left: 1rem;
}

.card {
  background: var(--surface);
  border: var(--border-width) solid var(--ink);
  border-radius: 20px;
  padding: 2rem;
  box-shadow: var(--shadow);
  margin-bottom: 2rem;
}

.blue-card {
  border-color: var(--accent-blue);
  box-shadow: 8px 8px 0px var(--accent-blue);
}

.teal-card {
  border-color: var(--accent-teal);
  box-shadow: 8px 8px 0px var(--accent-teal);
}

code,
pre {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.9rem;
}

pre {
  background: #f4f4f4;
  padding: 1.5rem;
  border: 2px solid var(--ink);
  border-radius: 12px;
  overflow-x: auto;
  margin: 1rem 0;
  position: relative;
  white-space: pre-wrap;
  word-break: break-word;
}

.copy-btn {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  background: var(--ink);
  color: #fff;
  border: none;
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
  font-size: 0.7rem;
  font-weight: 800;
  cursor: pointer;
  text-transform: uppercase;
}

.example-label {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  background: var(--accent-amber);
  border: 1px solid var(--ink);
  font-weight: 800;
  font-size: 0.7rem;
  border-radius: 4px;
  margin-bottom: 0.5rem;
}

.pro-tip {
  background: #fffcf0;
  padding: 1.2rem;
  border-radius: 12px;
  border: 2px dashed var(--accent-amber);
  margin: 1rem 0;
  font-size: 0.95rem;
}

/* ----- BUY ME A COFFEE ----- */
.bmc-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: #FFDD00;
  color: #000;
  border: 2px solid var(--ink);
  border-radius: 30px;
  padding: 0.35rem 0.85rem;
  font-family: 'Lexend', sans-serif;
  font-weight: 800;
  font-size: 0.72rem;
  text-decoration: none;
  box-shadow: 2px 2px 0px var(--ink);
  transition: 0.2s;
  white-space: nowrap;
  margin-top: 1rem;
}

.bmc-btn:hover {
  transform: translateY(-2px);
  box-shadow: 3px 3px 0px var(--ink);
}

.bmc-btn svg { width: 16px; height: 16px; flex-shrink: 0; }

footer {
  margin-top: 5rem;
  padding: 3rem 1rem;
  text-align: center;
  border-top: 3px solid var(--ink);
}

.footer-email {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--ink);
  text-decoration: none;
  font-weight: 700;
  opacity: 0.8;
  transition: 0.2s;
  border-bottom: 2px solid transparent;
}
.footer-email:hover {
  opacity: 1;
  border-bottom-color: var(--accent-blue);
}

@media (max-width: 768px) {
  body { padding: 0.75rem; overflow-x: hidden; }
  header { padding: 1.5rem; border-radius: 20px; margin-bottom: 2rem; }
  h1 { font-size: 1.5rem; }
  .back-btn { position: static; display: inline-block; margin-bottom: 1.5rem; }
  
  .card { padding: 1.5rem 1rem; border-radius: 16px; margin-bottom: 1.5rem; }
  h2 { font-size: 1.3rem; padding: 0.5rem 1.2rem; margin: 2.5rem 0 1rem; width: 100%; text-align: center; }
  h3 { font-size: 1.1rem; margin: 1.5rem 0 0.8rem; }
  
  pre { padding: 1rem; font-size: 0.8rem; border-radius: 8px; }
  
  footer { padding: 2rem 1rem; margin-top: 2rem; }
}