body {
  margin: 0;
  padding: 0;
  background: #f5f5f7;
  font-family:
    -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", sans-serif;
  color: #111;
}

/* IMPORTANT: prevents weird overflow issues */
* {
  box-sizing: border-box;
}

/* WRAPPER */
.about-container {
  max-width: 900px;
  margin: 40px auto;
  padding: 20px;
}

/* TOP BAR */
.top-bar {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 18px;
  margin-bottom: 25px;
}

.top-bar h1 {
  margin: 0;
  font-size: 28px;
  color: #111;
  line-height: 1.2;
}

/* BACK BUTTON */
.back-home {
  text-decoration: none;
  font-size: 14px;
  color: #0071e3;
  font-weight: 500;
}

.back-home:hover {
  text-decoration: underline;
}

/* CARD */
.about-card {
  background: #fff;
  border-radius: 24px;
  padding: 40px;

  box-shadow:
    0 20px 60px rgba(0, 0, 0, 0.08),
    0 2px 10px rgba(0, 0, 0, 0.04);
}

/* TEXT */
.intro {
  font-size: 15px;
  color: #444;
  line-height: 1.6;
  margin-bottom: 14px;
}

/* IMAGE SECTION */
.diagram-section {
  margin-top: 25px;
  text-align: center;
}

.diagram {
  max-width: 100%;
  height: auto;
  border-radius: 12px;
  border: 1px solid #eee;
  display: block;
  margin: 0 auto;
}

.diagram-notes {
  margin-top: 12px;
  font-size: 13px;
  color: #666;
  text-align: left;
  line-height: 1.5;
}

.diagram-notes p {
  margin: 8px 0;
}

/* HEADINGS */
.about-card h2 {
  margin-top: 30px;
  font-size: 18px;
  color: #222;
}

/* 🔥 CRITICAL FIX FOR FOOTER LAYOUT */
html,
body {
  width: 100%;
  overflow-x: hidden;
}

/* MOBILE */
@media (max-width: 768px) {
  .about-container {
    margin: 20px auto;
    padding: 16px;
  }

  .about-card {
    padding: 24px;
  }

  .top-bar h1 {
    font-size: 22px;
  }
}