:root {
  --color-canvas: #f7f7f5;
  --color-surface: #ffffff;
  --color-border: #e2e2dd;
  --color-border-strong: #c9c9c1;
  --color-text: #1a1a17;
  --color-text-muted: #6b6b63;
  --color-accent: #1f5c4d;
  --color-accent-soft: #eaf2ef;
  --color-error: #a4302a;
  --color-error-soft: #fdf1f0;

  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1.25rem;
  --space-lg: 2rem;

  --radius-sm: 10px;
  --radius-md: 18px;
  --card-max-width: 40rem;
  --progress-height: 4px;

  --transition-fast: 120ms ease;
  --slide-duration: 260ms;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--color-canvas);
  color: var(--color-text);
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

.page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: var(--space-lg) var(--space-md);
}

/* Progress bar pinned to the top of the viewport */

.progress {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 2;
  height: var(--progress-height);
  background: var(--color-border);
}

.progress__fill {
  height: 100%;
  width: 0;
  background: var(--color-accent);
  transition: width var(--slide-duration) ease;
}

/* Card */

.card {
  width: 100%;
  max-width: var(--card-max-width);
  padding: var(--space-lg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  box-shadow: 0 1px 2px rgb(0 0 0 / 4%), 0 12px 32px rgb(0 0 0 / 5%);
}

.card--intro {
  text-align: center;
}

.card__title {
  margin: 0;
  font-size: clamp(1.6rem, 4.5vw, 2.2rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.card__body {
  margin: var(--space-sm) 0 0;
  color: var(--color-text-muted);
}

.card__meta {
  margin: var(--space-md) 0 0;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.eyebrow {
  margin: 0 0 var(--space-xs);
  color: var(--color-accent);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.card--intro .button {
  margin-top: var(--space-lg);
}

/* Deck of slides: only the active slide is in the layout */

.deck {
  min-height: 19rem;
}

.slide {
  display: none;
}

.slide--active {
  display: block;
  animation: slide-in var(--slide-duration) ease both;
}

@keyframes slide-in {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.slide__counter {
  margin: 0 0 var(--space-xs);
  color: var(--color-accent);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.slide__prompt {
  display: block;
  margin: 0 0 var(--space-xs);
  padding: 0;
  font-size: clamp(1.25rem, 3.5vw, 1.6rem);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.slide__hint {
  margin: 0 0 var(--space-md);
  color: var(--color-text-muted);
  font-size: 0.88rem;
}

.slide__required {
  margin-left: 0.3rem;
  color: var(--color-error);
}

/* Options */

.option {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  margin-bottom: var(--space-xs);
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-fast), border-color var(--transition-fast);
}

.option:hover {
  border-color: var(--color-border-strong);
  background: var(--color-accent-soft);
}

.option:has(input:checked) {
  border-color: var(--color-accent);
  background: var(--color-accent-soft);
}

.option:has(input:focus-visible) {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.option input {
  flex: none;
  width: 1.15rem;
  height: 1.15rem;
  margin: 0.2rem 0 0;
  accent-color: var(--color-accent);
}

/* Text inputs */

.text-input,
.text-area {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: inherit;
  font: inherit;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.text-area {
  min-height: 8rem;
  resize: vertical;
}

.text-input:focus,
.text-area:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}

/* Instagram handle gets a leading @ so the field reads unambiguously */

.handle {
  display: flex;
  align-items: center;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.handle:focus-within {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}

.handle__prefix {
  padding-left: var(--space-md);
  color: var(--color-text-muted);
}

.handle .text-input {
  border: none;
  padding-left: 0.2rem;
  background: transparent;
}

.handle .text-input:focus {
  box-shadow: none;
}

.counter {
  margin: var(--space-xs) 0 0;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

/* Honeypot: hidden from people, reachable by naive bots */

.honeypot {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

/* Navigation */

.nav {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-top: var(--space-lg);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
}

.nav__position {
  flex: 1;
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  text-align: center;
  font-variant-numeric: tabular-nums;
}

.nav__hint {
  margin: var(--space-sm) 0 0;
  color: var(--color-text-muted);
  font-size: 0.78rem;
  text-align: center;
}

/* Buttons */

.button {
  padding: var(--space-sm) var(--space-lg);
  border: none;
  border-radius: var(--radius-sm);
  background: var(--color-accent);
  color: #fff;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  transition: opacity var(--transition-fast), transform var(--transition-fast);
}

.button:hover:not(:disabled) {
  opacity: 0.92;
}

.button:active:not(:disabled) {
  transform: translateY(1px);
}

.button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.button--quiet {
  border: 1px solid var(--color-border-strong);
  background: transparent;
  color: var(--color-text-muted);
}

.button--quiet:hover:not(:disabled) {
  border-color: var(--color-text-muted);
  color: var(--color-text);
}

/* Messages */

.error {
  margin: var(--space-md) 0 0;
  padding: var(--space-sm) var(--space-md);
  border-left: 3px solid var(--color-error);
  border-radius: var(--radius-sm);
  background: var(--color-error-soft);
  color: var(--color-error);
  font-size: 0.92rem;
}

.field-invalid {
  border-color: var(--color-error);
}

@media (prefers-reduced-motion: reduce) {
  .slide--active {
    animation: none;
  }

  .progress__fill {
    transition: none;
  }
}

@media (max-width: 30rem) {
  .card {
    padding: var(--space-md);
  }

  .deck {
    min-height: 16rem;
  }

  .button {
    padding: var(--space-sm) var(--space-md);
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-canvas: #16171a;
    --color-surface: #1e2024;
    --color-border: #30333a;
    --color-border-strong: #454a53;
    --color-text: #eceded;
    --color-text-muted: #9ba1ab;
    --color-accent: #5fbfa5;
    --color-accent-soft: #23302d;
    --color-error: #f0857d;
    --color-error-soft: #2c1f1f;
  }

  .button {
    color: #10231e;
  }

  .button--quiet {
    color: var(--color-text-muted);
  }
}