🔘 Radio Button

<div class="radio-group">
  <label class="radio-custom">
    <input type="radio" name="plan" checked>
    <span class="radio-custom-mark"></span>
    <span>Basic</span>
  </label>
  <label class="radio-custom">
    <input type="radio" name="plan">
    <span class="radio-custom-mark"></span>
    <span>Pro</span>
  </label>
  <label class="radio-custom">
    <input type="radio" name="plan">
    <span class="radio-custom-mark"></span>
    <span>Enterprise</span>
  </label>
</div>

.radio-group {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.radio-custom {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  cursor: pointer;
  user-select: none;
}
.radio-custom input {
  display: none;
}
.radio-custom-mark {
  width: 22px;
  height: 22px;
  border: 2px solid #d0d0d0;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  flex-shrink: 0;
}
.radio-custom input:checked + .radio-custom-mark {
  border-color: #667eea;
}
.radio-custom input:checked + .radio-custom-mark::after {
  content: '';
  width: 12px;
  height: 12px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 50%;
}

<div class="radio-cards">
  <label class="radio-card">
    <input type="radio" name="size" checked>
    <div class="radio-card-content">
      <div class="radio-card-title">Small</div>
      <div class="radio-card-desc">8" × 10"</div>
    </div>
  </label>
  <label class="radio-card">
    <input type="radio" name="size">
    <div class="radio-card-content">
      <div class="radio-card-title">Medium</div>
      <div class="radio-card-desc">12" × 16"</div>
    </div>
  </label>
  <label class="radio-card">
    <input type="radio" name="size">
    <div class="radio-card-content">
      <div class="radio-card-title">Large</div>
      <div class="radio-card-desc">18" × 24"</div>
    </div>
  </label>
</div>

.radio-cards {
  display: flex;
  gap: 0.75rem;
}
.radio-card {
  cursor: pointer;
  user-select: none;
}
.radio-card input {
  display: none;
}
.radio-card-content {
  padding: 1rem 1.25rem;
  border: 2px solid #e0e0e0;
  border-radius: 10px;
  transition: all 0.2s ease;
  min-width: 90px;
  text-align: center;
}
.radio-card:hover .radio-card-content {
  border-color: #667eea;
}
.radio-card input:checked + .radio-card-content {
  border-color: #667eea;
  background: rgba(102, 126, 234, 0.05);
}
.radio-card-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #1a1a2e;
  margin-bottom: 0.25rem;
}
.radio-card-desc {
  font-size: 0.8rem;
  color: #666;
}

<div class="radio-group">
  <label class="radio-grad">
    <input type="radio" name="color" checked>
    <span class="radio-grad-mark"></span>
    <span>Red</span>
  </label>
  <label class="radio-grad">
    <input type="radio" name="color">
    <span class="radio-grad-mark"></span>
    <span>Blue</span>
  </label>
  <label class="radio-grad">
    <input type="radio" name="color">
    <span class="radio-grad-mark"></span>
    <span>Green</span>
  </label>
</div>

.radio-group {
  display: flex;
  gap: 1.5rem;
}
.radio-grad {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  user-select: none;
}
.radio-grad input {
  display: none;
}
.radio-grad-mark {
  width: 24px;
  height: 24px;
  border: 2px solid #d0d0d0;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
}
.radio-grad input:checked + .radio-grad-mark {
  border-color: transparent;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
}
.radio-grad input:checked + .radio-grad-mark::after {
  content: '';
  width: 8px;
  height: 8px;
  background: white;
  border-radius: 50%;
}