```css
/* TouchGrass AI - Styles */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: Arial, sans-serif;
  background: #f3f8f0;
  color: #203629;
  line-height: 1.6;
}

header {
  background: #174c35;
  color: white;
  text-align: center;
  padding: 28px 16px;
}

header h1 {
  font-size: 2.2rem;
  margin-bottom: 5px;
}

header p {
  color: #d5ead9;
}

main {
  width: min(900px, 92%);
  margin: 30px auto;
}

.hero {
  text-align: center;
  padding: 55px 22px;
  border-radius: 20px;
  background: linear-gradient(135deg, #d7efd2, #b5dfbd);
  margin-bottom: 28px;
}

.hero h2 {
  font-size: clamp(1.7rem, 4vw, 2.5rem);
  color: #174c35;
  margin-bottom: 12px;
}

.hero p {
  margin-bottom: 25px;
}

.btn,
button {
  display: inline-block;
  border: none;
  border-radius: 10px;
  padding: 13px 20px;
  font-size: 1rem;
  font-weight: bold;
  cursor: pointer;
  transition: 0.2s ease;
}

.btn {
  background: #174c35;
  color: white;
  text-decoration: none;
}

button {
  background: #247348;
  color: white;
  width: 100%;
  margin-top: 18px;
}

.btn:hover,
button:hover {
  background: #103b28;
  transform: translateY(-2px);
}

button:focus-visible,
a:focus-visible,
select:focus-visible {
  outline: 3px solid #e0a83e;
  outline-offset: 3px;
}

.panel {
  background: white;
  padding: 28px;
  border-radius: 18px;
  box-shadow: 0 8px 25px #183e2412;
}

.panel h2 {
  color: #174c35;
  margin-bottom: 20px;
}

label {
  display: block;
  font-weight: bold;
  margin: 16px 0 7px;
}

select {
  width: 100%;
  padding: 13px;
  border: 1px solid #cbd9cb;
  border-radius: 9px;
  background: #fbfdf9;
  color: #203629;
  font-size: 1rem;
}

#result {
  background: #edf7eb;
  border-left: 5px solid #3b8c55;
  border-radius: 10px;
  padding: 20px;
  margin-top: 24px;
}

#result h3 {
  color: #174c35;
  margin-bottom: 8px;
}

#result p {
  margin-bottom: 8px;
}

#complete {
  background: #dcefe0;
  color: #174c35;
}

#complete:hover {
  background: #c5e3cc;
}

#progress {
  text-align: center;
  font-weight: bold;
  margin-top: 18px;
  color: #247348;
}

footer {
  text-align: center;
  padding: 25px 15px;
  color: #536957;
  font-size: 0.9rem;
}

@media (max-width: 600px) {
  header h1 {
    font-size: 1.8rem;
  }

  .hero {
    padding: 35px 18px;
  }

  .panel {
    padding: 20px;
  }

  .btn {
    font-size: 0.9rem;
  }
}
```