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

:root {
  color-scheme: only light;
}

body {
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  background: #fff;
  color: #000;
  text-transform: lowercase;
  letter-spacing: 0.02em;
  line-height: 1.5;
}

a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid #000;
  padding-bottom: 2px;
}

main {
  max-width: 880px;
  margin: 48px auto;
  padding: 0 24px 80px;
}

header {
  margin-bottom: 32px;
}

h1 {
  font-size: 32px;
  font-weight: 500;
  margin-bottom: 18px;
}

nav {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
}

.section-title {
  font-size: 18px;
  font-weight: 500;
  margin: 28px 0 12px;
}

.onboarding-intro {
  max-width: 620px;
  margin-bottom: 24px;
}

.onboarding-form {
  border: 1px solid #000;
  padding: 24px;
  box-shadow:
    0 0 0 2px #fff,
    0 0 22px rgba(0, 0, 0, 0.08);
}

.onboarding-list {
  list-style: none;
  display: grid;
  gap: 18px;
}

.onboarding-list li {
  border: 1px solid #000;
  padding: 14px 16px;
  background: #fff;
  box-shadow:
    0 0 0 2px #fff,
    0 0 14px rgba(0, 0, 0, 0.06);
}

.onboarding-list label {
  display: block;
  font-weight: 500;
  margin-bottom: 10px;
}

.scale {
  display: flex;
  align-items: center;
  gap: 12px;
}

.scale span {
  font-size: 12px;
  letter-spacing: 0.08em;
}

.scale-options {
  display: grid;
  grid-auto-flow: column;
  gap: 8px;
}

.scale-options input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.scale-options label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border: 1px solid #000;
  font-size: 12px;
  cursor: pointer;
  box-shadow: 0 0 0 2px #fff;
}

.scale-options input:checked + label {
  background: #000;
  color: #fff;
}

.form-note {
  margin: 18px 0 12px;
  font-size: 12px;
  letter-spacing: 0.08em;
}

.ghost-button {
  border: 1px solid #000;
  padding: 10px 16px;
  background: transparent;
  font-size: 12px;
  letter-spacing: 0.08em;
}

.ghost-button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.rings-layout {
  display: flex;
  align-items: center;
  gap: 32px;
  flex-wrap: wrap;
}

.ring-graphic {
  position: relative;
  width: 320px;
  height: 320px;
  margin: 24px 0 24px;
}

.ring {
  position: absolute;
  border: 1px solid #000;
  border-radius: 50%;
  text-align: center;
}

.ring span {
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translate(-50%, 0);
  font-size: 16px;
  font-weight: 500;
  background: #fff;
  padding: 2px 8px;
  line-height: 1;
  box-shadow: 0 0 0 4px #fff;
}

.ring.outer {
  inset: 0;
}

.ring.ring-2 {
  inset: 28px;
}

.ring.ring-3 {
  inset: 56px;
}

.ring.ring-4 {
  inset: 84px;
}

.ring.ring-5 {
  inset: 112px;
}

.ring-key {
  min-width: 220px;
  max-width: 320px;
  margin: 24px 0;
}

.ring-key p {
  margin-bottom: 8px;
}

.placeholder {
  margin-top: 12px;
  max-width: 560px;
}

@media (max-width: 600px) {
  h1 {
    font-size: 26px;
  }

  nav {
    gap: 12px;
  }

  .ring-graphic {
    width: 260px;
    height: 260px;
  }

  .ring span {
    font-size: 14px;
  }

  .ring-key {
    min-width: 200px;
  }

  .onboarding-form {
    padding: 18px;
  }

  .onboarding-list li {
    padding: 12px 14px;
  }

  .scale {
    flex-wrap: wrap;
  }
}