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

* {
  margin: 0;
  padding: 0;
}

:root {
  --bg: #fafafa;
  --text: #343c3c;
  --text-muted: #5e6666;
  --accent: #abb495;
  --font-sans: 'Satoshi Variable', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size: 14px;
  --font-size-small: 13px;
  --transition: 150ms ease;
}

html {
  background-color: var(--bg);
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size);
  font-weight: 450;
  line-height: 1.5;
  color: var(--text);
  background-color: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
}

::selection {
  background-color: var(--accent);
  color: var(--bg);
}

/* Layout: pinned top-left */
main {
  max-width: 560px;
  margin: 0;
  padding: 3rem 1.5rem 4rem;
}

/* Progress */
.progress {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 2.5rem;
  font-size: var(--font-size-small);
}

.progress .step {
  color: var(--text-muted);
  background: none;
  border: none;
  padding: 0;
  font-family: var(--font-sans);
  font-size: var(--font-size-small);
  font-weight: 450;
  cursor: default;
  transition: color var(--transition);
}

.progress button.step.completed {
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 2px;
}

.progress button.step.completed:hover {
  color: var(--accent);
}

.progress .step.active {
  color: var(--text);
}

.progress .step.completed {
  color: var(--text);
}

.progress .step.future,
.progress .step.locked {
  color: var(--text-muted);
  opacity: 0.4;
  cursor: default;
  text-decoration: none;
  pointer-events: none;
}

/* Form steps */
.form-step {
  display: none;
  opacity: 0;
}

.form-step.active {
  display: block;
  animation: fadeIn 150ms ease forwards;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

h1 {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 1.5rem;
}

/* Fieldset reset */
fieldset {
  border: none;
  padding: 0;
  margin: 0;
}

fieldset legend {
  display: block;
  font-size: var(--font-size);
  color: var(--text);
  margin-bottom: 0.25rem;
  line-height: 1.4;
  padding: 0;
}

/* Fields */
.field,
.budget-fieldset {
  margin-bottom: 1.75rem;
}

/* Question numbers */
.q-num {
  color: var(--text-muted);
  margin-right: 0.15rem;
}

.field label {
  display: block;
  font-size: var(--font-size);
  color: var(--text);
  margin-bottom: 0.25rem;
  line-height: 1.4;
}

.field .optional,
.field .hint {
  color: var(--text-muted);
  font-size: var(--font-size-small);
}

.field input[type="text"],
.field input[type="email"],
.field input[type="tel"],
.field input[type="url"],
.field input[type="number"],
.field input[type="date"],
.field textarea {
  display: block;
  padding: 0.35rem 0;
  font-family: var(--font-sans);
  font-size: var(--font-size);
  font-weight: 450;
  color: var(--text);
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--text-muted);
  border-radius: 0;
  outline: none;
  transition: border-color var(--transition);
  -webkit-appearance: none;
  appearance: none;
}

.field input::placeholder,
.field textarea::placeholder {
  color: var(--text-muted);
  opacity: 0.6;
  transition: opacity var(--transition);
}

.field input:focus::placeholder,
.field textarea:focus::placeholder {
  opacity: 0;
}

.field input:focus,
.field textarea:focus {
  border-bottom-color: var(--text);
}

.field textarea {
  resize: none;
  line-height: 1.5;
  overflow: hidden;
  width: 100%;
}

/* Proportional widths */
.input-short { width: 160px; max-width: 100%; }
.input-medium { width: 260px; max-width: 100%; }
.input-long { width: 380px; max-width: 100%; }

/* Handle inputs (@username) */
.handle-input {
  display: inline-flex;
  align-items: center;
  width: 160px;
  max-width: 100%;
}

.handle-prefix {
  color: var(--text-muted);
  font-size: var(--font-size);
  padding: 0.35rem 0;
  margin-right: 0.1rem;
  user-select: none;
}

.handle-input input {
  flex: 1;
}

/* Field description */
.field-description {
  display: block;
  font-size: var(--font-size-small);
  color: var(--text-muted);
  margin-bottom: 0.25rem;
  line-height: 1.4;
}

/* Validation */
.field .error {
  display: none;
  font-size: var(--font-size-small);
  color: #8b3a3a;
  margin-top: 0.25rem;
}

.field.invalid input,
.field.invalid textarea {
  border-bottom-color: #8b3a3a;
}

.field.invalid .error {
  display: block;
}

/* Budget */
.budget-group {
  display: flex;
  gap: 1.5rem;
  margin-top: 0.25rem;
}

.radio-label {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  cursor: pointer;
  font-size: var(--font-size);
  color: var(--text);
}

.radio-label input[type="radio"] {
  width: 14px;
  height: 14px;
  accent-color: var(--text);
  cursor: pointer;
}

.budget-amount {
  margin-top: 0.5rem;
}

.budget-amount .currency-input {
  display: flex;
  align-items: center;
}

.budget-amount .field-description {
  margin-top: 0.25rem;
}

.budget-amount.hidden,
.budget-trade.hidden {
  display: none;
}

.budget-trade {
  margin-top: 0.5rem;
}

.currency-symbol {
  color: var(--text-muted);
  font-size: var(--font-size);
  margin-right: 0.2rem;
}

/* Buttons */
.btn-next,
.btn-back {
  font-family: var(--font-sans);
  font-size: var(--font-size);
  font-weight: 450;
  color: var(--text);
  background: transparent;
  border: none;
  padding: 0;
  cursor: pointer;
  transition: color var(--transition);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.btn-next:hover,
.btn-back:hover {
  color: var(--accent);
}

.btn-next:focus-visible,
.btn-back:focus-visible,
.btn-submit:focus-visible {
  outline: 1px solid var(--text);
  outline-offset: 2px;
}

.btn-submit {
  font-family: var(--font-sans);
  font-size: var(--font-size);
  font-weight: 450;
  color: var(--text);
  background: transparent;
  border: none;
  padding: 0;
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: color var(--transition);
}

.btn-submit:hover {
  color: var(--accent);
}

.btn-submit:disabled {
  cursor: default;
  text-decoration: none;
  animation: blink 1s ease-in-out infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.step-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Confirmation */
.confirmation p {
  margin-bottom: 0.75rem;
}

.confirmation a {
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: color var(--transition);
}

.confirmation a:hover,
.privacy-note a:hover {
  color: var(--accent);
}

.privacy-note {
  margin-bottom: 1.5rem;
}

.privacy-note a {
  color: var(--text-muted);
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* Date input */
input[type="date"] {
  color-scheme: light;
}

input[type="date"]::-webkit-calendar-picker-indicator {
  opacity: 0.4;
  cursor: pointer;
}

/* Remove number spinners */
input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

input[type="number"] {
  -moz-appearance: textfield;
}

/* Mobile */
@media (max-width: 600px) {
  main {
    padding: 2rem 1rem 3rem;
    max-width: none;
  }

  .input-short,
  .input-medium,
  .input-long {
    width: 100%;
  }

  .handle-input {
    width: 100%;
  }

  .progress {
    gap: 1rem;
  }
}