:root {
  --color-bg: #0f1115;
  --color-surface: #1a1d24;
  --color-text: #f2f3f5;
  --color-muted: #9aa0ab;
  --color-primary: #4f8ef7;
  --color-primary-text: #0b0d10;
  --color-back: #2a2e37;
  --radius: 12px;
  --gap: 16px;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
}

body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 18px;
  line-height: 1.4;
}

#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.screen {
  display: flex;
  flex-direction: column;
  gap: var(--gap);
  padding: 24px 20px;
  flex: 1;
}

.screen h1 {
  font-size: 28px;
  margin: 0 0 8px;
}

.screen h2 {
  font-size: 24px;
  margin: 0 0 8px;
}

button {
  font-size: 18px;
  padding: 18px;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  min-height: 56px;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-primary-text);
  font-weight: 600;
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-muted);
}

.btn-back {
  background: var(--color-back);
  color: var(--color-text);
}

.nav-row {
  display: flex;
  gap: var(--gap);
  margin-top: auto;
}

.nav-row .btn-back {
  flex: 1;
}

.nav-row .btn-primary {
  flex: 2;
}

.progress {
  color: var(--color-muted);
  font-size: 14px;
  margin: 0;
}

.pacing-note {
  background: var(--color-surface);
  border-left: 4px solid var(--color-primary);
  padding: 12px;
  border-radius: 8px;
  font-size: 16px;
}

#timer-display {
  font-size: 40px;
  font-weight: 700;
  text-align: center;
}

.full-plan ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
  overflow-y: auto;
}

.full-plan li {
  background: var(--color-surface);
  padding: 12px;
  border-radius: 8px;
}

.full-plan .ref {
  color: var(--color-muted);
  font-size: 13px;
  font-weight: normal;
}

@media (min-width: 600px) {
  .screen {
    max-width: 480px;
    margin: 0 auto;
    width: 100%;
  }
}