:root {
  --bg: #f8fbff;
  --card: #ffffff;
  --text: #16324f;
  --muted: #4c6a8a;
  --accent: #4b8bf4;
  --accent-soft: #e8f0ff;
  --border: #d8e4f5;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Trebuchet MS", "Arial Rounded MT Bold", Arial, sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, var(--bg) 0%, #eef6ff 100%);
}

.page-header {
  text-align: center;
  padding: 2rem 1rem 1rem;
}

.page-header h1 {
  margin: 0;
  font-size: 2rem;
}

.page-header p {
  margin-top: 0.5rem;
  color: var(--muted);
}

.layout {
  display: grid;
  grid-template-columns: minmax(220px, 300px) 1fr;
  gap: 1rem;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1rem 1.5rem;
}

.launcher-panel,
.runner-panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1rem;
  box-shadow: 0 10px 24px rgba(22, 50, 79, 0.08);
}

.app-list {
  display: grid;
  gap: 0.75rem;
}

.app-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.75rem;
  text-align: left;
  background: #fff;
  color: inherit;
  cursor: pointer;
}

.app-card:hover,
.app-card:focus-visible {
  border-color: var(--accent);
  outline: none;
}

.app-card.active {
  background: var(--accent-soft);
  border-color: var(--accent);
}

.app-card h3 {
  margin: 0;
  font-size: 1rem;
}

.app-card p {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.runner-heading h2 {
  margin: 0;
}

.runner-heading p {
  margin: 0.35rem 0 0.75rem;
  color: var(--muted);
}

#app-frame {
  width: 100%;
  height: 560px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
}

@media (max-width: 860px) {
  .layout {
    grid-template-columns: 1fr;
  }

  #app-frame {
    height: 440px;
  }
}