/* ============================================================
  ADHD Buddy Marketing Site — styles.css
   Lean, accessible, neurodiverse-friendly design system
   ============================================================ */

/* ---------- Reset & Base ---------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* Brand colors */
  --color-primary:     #5C6BF0;   /* indigo — calm & focused */
  --color-primary-dk:  #4453D6;
  --color-primary-lt:  #EEF0FD;
  --color-accent:      #22C55E;   /* green — positive action */
  --color-accent-dk:   #16A34A;
  --color-warn:        #F59E0B;
  --color-danger:      #EF4444;
  --color-white:       #FFFFFF;

  /* Neutrals */
  --color-bg:          #F8F9FF;
  --color-surface:     #FFFFFF;
  --color-border:      #E2E5F1;
  --color-text:        #1A1C2E;
  --color-muted:       #6B7280;
  --color-label:       #374151;

  /* Typography */
  --font-sans:         'Inter', system-ui, -apple-system, sans-serif;
  --font-size-xs:      0.75rem;   /* 12px */
  --font-size-sm:      0.875rem;  /* 14px */
  --font-size-base:    1rem;      /* 16px */
  --font-size-lg:      1.125rem;  /* 18px */
  --font-size-xl:      1.25rem;   /* 20px */
  --font-size-2xl:     1.5rem;    /* 24px */
  --font-size-3xl:     1.875rem;  /* 30px */
  --font-size-4xl:     2.25rem;   /* 36px */
  --font-size-5xl:     3rem;      /* 48px */

  /* Spacing */
  --space-1:   0.25rem;
  --space-2:   0.5rem;
  --space-3:   0.75rem;
  --space-4:   1rem;
  --space-5:   1.25rem;
  --space-6:   1.5rem;
  --space-8:   2rem;
  --space-10:  2.5rem;
  --space-12:  3rem;
  --space-16:  4rem;
  --space-20:  5rem;
  --space-24:  6rem;

  /* Layout */
  --max-width:    1100px;
  --radius-sm:    6px;
  --radius-md:    10px;
  --radius-lg:    16px;
  --radius-full:  9999px;

  /* Shadows */
  --shadow-sm:  0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md:  0 4px 16px rgba(0,0,0,0.08), 0 2px 6px rgba(0,0,0,0.04);
  --shadow-lg:  0 20px 40px rgba(0,0,0,0.10), 0 8px 16px rgba(0,0,0,0.06);

  /* Transitions */
  --transition: 0.2s ease;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Reduce motion for users who prefer it */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* Focus styles — accessibility */
:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 2px;
}
a:hover { color: var(--color-primary-dk); }

/* ---------- Layout Helpers ---------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.section {
  padding-block: var(--space-20);
}

.section--tight {
  padding-block: var(--space-8);
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin-inline: auto;
  margin-bottom: var(--space-12);
}

.section-label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}

.section-sub {
  font-size: var(--font-size-lg);
  color: var(--color-muted);
  margin-top: var(--space-3);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  border: none;
  cursor: pointer;
  font-family: var(--font-sans);
  font-weight: 600;
  text-decoration: none;
  transition: background var(--transition), color var(--transition),
              border-color var(--transition), box-shadow var(--transition),
              transform var(--transition);
  border-radius: var(--radius-md);
  white-space: nowrap;
  -webkit-appearance: none;
  appearance: none;
}

.btn:active { transform: translateY(1px); }

/* Sizes */
.btn--sm  { padding: var(--space-2) var(--space-4);   font-size: var(--font-size-sm); }
.btn--md  { padding: var(--space-3) var(--space-6);   font-size: var(--font-size-base); }
.btn--lg  { padding: var(--space-4) var(--space-8);   font-size: var(--font-size-lg); }
.btn--full { width: 100%; }

/* Primary */
.btn--primary {
  background: var(--color-primary);
  color: var(--color-white);
  box-shadow: var(--shadow-sm);
}
.btn--primary:hover {
  background: var(--color-primary-dk);
  box-shadow: var(--shadow-md);
  color: var(--color-white);
  text-decoration: none;
}

/* Outline */
.btn--outline {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}
.btn--outline:hover {
  background: var(--color-primary-lt);
  text-decoration: none;
}

/* Ghost */
.btn--ghost {
  background: transparent;
  color: var(--color-muted);
  border: 1px solid var(--color-border);
}
.btn--ghost:hover {
  background: var(--color-surface);
  color: var(--color-text);
  border-color: var(--color-text);
  text-decoration: none;
}

/* White (on dark bg) */
.btn--white {
  background: var(--color-white);
  color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}
.btn--white:hover {
  box-shadow: var(--shadow-md);
  text-decoration: none;
}

/* ---------- Navigation ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(248, 249, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-4);
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
  color: var(--color-text);
  font-size: var(--font-size-lg);
}

.logo-icon { font-size: 1.4rem; }

.logo-text {
  font-weight: 500;
  letter-spacing: -0.02em;
}

.logo-text strong { font-weight: 800; color: var(--color-primary); }

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(160deg, #EEF0FD 0%, #F8F9FF 60%, #F0FDF4 100%);
  text-align: center;
  padding-block: var(--space-24) var(--space-20);
}

.hero__inner {
  max-width: 820px;
}

.pill {
  display: inline-block;
  background: var(--color-primary-lt);
  color: var(--color-primary);
  border: 1px solid #c7ccf7;
  font-size: var(--font-size-sm);
  font-weight: 600;
  padding: var(--space-1) var(--space-4);
  border-radius: var(--radius-full);
  margin-bottom: var(--space-6);
}

.hero__title {
  font-size: clamp(var(--font-size-3xl), 6vw, var(--font-size-5xl));
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-6);
}

.highlight {
  color: var(--color-primary);
  background: linear-gradient(135deg, #5C6BF0, #7B8BF5);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__sub {
  font-size: clamp(var(--font-size-base), 2.2vw, var(--font-size-xl));
  color: var(--color-muted);
  max-width: 640px;
  margin-inline: auto;
  margin-bottom: var(--space-8);
  line-height: 1.7;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  justify-content: center;
  margin-bottom: var(--space-6);
}

.hero__social-proof {
  font-size: var(--font-size-sm);
  color: var(--color-muted);
}

/* ---------- Problem Strip ---------- */
.problem-strip {
  background: var(--color-text);
  color: var(--color-white);
}

.strip__label {
  text-align: center;
  font-size: var(--font-size-sm);
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #9CA3AF;
  margin-bottom: var(--space-4);
}

.strips {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  justify-content: center;
}

.strip-tag {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-full);
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-sm);
  font-weight: 500;
}

/* ---------- Features Section ---------- */
.how {
  background: var(--color-surface);
}

.how h2 {
  font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-4xl));
  font-weight: 800;
  letter-spacing: -0.02em;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-5);
  margin-bottom: var(--space-12);
}

.feature-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: box-shadow var(--transition), border-color var(--transition);
}

.feature-card:hover {
  box-shadow: var(--shadow-md);
  border-color: #c7ccf7;
}

.feature-card--highlight {
  background: var(--color-primary-lt);
  border-color: #c7ccf7;
}

.feature-icon {
  font-size: 1.8rem;
  margin-bottom: var(--space-3);
  display: block;
}

.feature-card h3 {
  font-size: var(--font-size-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
  letter-spacing: -0.01em;
}

.feature-card p {
  font-size: var(--font-size-sm);
  color: var(--color-muted);
  line-height: 1.65;
}

.badge {
  display: inline-block;
  margin-top: var(--space-4);
  font-size: var(--font-size-xs);
  font-weight: 600;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  background: var(--color-border);
  color: var(--color-muted);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.badge--launch {
  background: #dcfce7;
  color: #166534;
}

/* Differentiators */
.differentiators {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
  gap: var(--space-6);
  background: var(--color-text);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
}

.diff-item {
  display: flex;
  gap: var(--space-4);
  align-items: flex-start;
}

.diff-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
  margin-top: 2px;
}

.diff-item strong {
  display: block;
  color: var(--color-white);
  font-size: var(--font-size-base);
  font-weight: 700;
  margin-bottom: var(--space-1);
}

.diff-item p {
  font-size: var(--font-size-sm);
  color: #9CA3AF;
  line-height: 1.55;
}

/* ---------- Lean Proof ---------- */
.lean-proof {
  background: var(--color-bg);
}

.lean-proof h2 {
  font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-4xl));
  font-weight: 800;
  letter-spacing: -0.02em;
}

.hypothesis-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--space-6);
}

.hypo-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
}

.hypo-number {
  display: inline-block;
  background: var(--color-primary-lt);
  color: var(--color-primary);
  font-size: var(--font-size-xs);
  font-weight: 800;
  letter-spacing: 0.1em;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  margin-bottom: var(--space-3);
  text-transform: uppercase;
}

.hypo-card h3 {
  font-size: var(--font-size-lg);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-3);
}

.hypo-card p {
  font-size: var(--font-size-sm);
  color: var(--color-muted);
  line-height: 1.65;
  margin-bottom: var(--space-5);
}

.hypo-vote {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.vote-btn {
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  border: 1.5px solid var(--color-border);
  background: transparent;
  font-size: var(--font-size-sm);
  font-weight: 600;
  cursor: pointer;
  font-family: var(--font-sans);
  transition: background var(--transition), border-color var(--transition);
}

.vote-btn:hover {
  background: var(--color-primary-lt);
  border-color: var(--color-primary);
}

.vote-btn--selected {
  background: var(--color-primary-lt);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.vote-count {
  font-size: var(--font-size-xs);
  color: var(--color-muted);
  font-style: italic;
}

/* ---------- Feedback Form ---------- */
.feedback {
  background: var(--color-surface);
}

.feedback__inner {
  max-width: 720px;
}

.feedback__header {
  margin-bottom: var(--space-10);
}

.feedback__header h2 {
  font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-4xl));
  font-weight: 800;
  letter-spacing: -0.02em;
}

/* Form groups */
.form-group {
  margin-bottom: var(--space-8);
}

fieldset.form-group {
  border: none;
}

.form-label {
  display: block;
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-label);
  margin-bottom: var(--space-3);
  line-height: 1.4;
}

.form-label span[aria-hidden="true"] {
  color: var(--color-danger);
}

.form-hint {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: 400;
  color: var(--color-muted);
  margin-top: var(--space-1);
}

/* Inputs */
.form-input,
.form-select,
.form-textarea {
  width: 100%;
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background: var(--color-bg);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-3) var(--space-4);
  transition: border-color var(--transition), box-shadow var(--transition);
  -webkit-appearance: none;
  appearance: none;
  line-height: 1.5;
}

.form-input:hover,
.form-select:hover,
.form-textarea:hover {
  border-color: #a5b4fc;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(92,107,240,0.15);
  background: var(--color-white);
}

.form-input.error,
.form-select.error,
.form-textarea.error {
  border-color: var(--color-danger);
}

.form-select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='%236B7280' viewBox='0 0 16 16'%3E%3Cpath d='M7.247 11.14 2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--space-4) center;
  padding-right: var(--space-10);
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

/* Radio / Checkbox */
.radio-group,
.checkbox-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.radio-label,
.checkbox-label {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  cursor: pointer;
  font-size: var(--font-size-base);
  line-height: 1.4;
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: background var(--transition), border-color var(--transition);
}

.radio-label:hover,
.checkbox-label:hover {
  background: var(--color-primary-lt);
  border-color: var(--color-primary);
}

.radio-label input,
.checkbox-label input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

/* Custom radio */
.radio-custom {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: border-color var(--transition), background var(--transition);
  background: var(--color-white);
}

.radio-label input:checked ~ .radio-custom {
  border-color: var(--color-primary);
  background: var(--color-primary);
  box-shadow: inset 0 0 0 3px var(--color-white);
}

/* Custom checkbox */
.checkbox-custom {
  width: 18px;
  height: 18px;
  border-radius: 4px;
  border: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: border-color var(--transition), background var(--transition);
  background: var(--color-white);
}

.checkbox-label input:checked ~ .checkbox-custom {
  border-color: var(--color-primary);
  background: var(--color-primary);
}

.checkbox-label input:checked ~ .checkbox-custom::after {
  content: '';
  display: block;
  width: 5px;
  height: 9px;
  border: 2px solid white;
  border-top: 0;
  border-left: 0;
  transform: rotate(45deg) translate(-1px, -1px);
}

.radio-label input:focus-visible ~ .radio-custom,
.checkbox-label input:focus-visible ~ .checkbox-custom {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

/* Error / char count */
.field-error {
  display: block;
  font-size: var(--font-size-sm);
  color: var(--color-danger);
  margin-top: var(--space-2);
  font-weight: 500;
  min-height: 1.25em;
}

.textarea-footer {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-top: var(--space-2);
}

.char-count {
  font-size: var(--font-size-xs);
  color: var(--color-muted);
  flex-shrink: 0;
  margin-left: auto;
}

/* Submit area */
.form-submit {
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
}

.form-privacy {
  text-align: center;
  font-size: var(--font-size-sm);
  color: var(--color-muted);
  margin-top: var(--space-4);
}

/* Success state */
.form-success {
  text-align: center;
  padding: var(--space-12) var(--space-6);
}

.success-icon {
  font-size: 3rem;
  margin-bottom: var(--space-4);
}

.form-success h3 {
  font-size: var(--font-size-2xl);
  font-weight: 800;
  margin-bottom: var(--space-4);
  letter-spacing: -0.02em;
}

.form-success p {
  font-size: var(--font-size-base);
  color: var(--color-muted);
  max-width: 480px;
  margin-inline: auto;
  margin-bottom: var(--space-3);
  line-height: 1.65;
}

.form-success .btn { margin-top: var(--space-6); }

/* ---------- Waitlist Strip ---------- */
.waitlist {
  background: linear-gradient(135deg, var(--color-primary) 0%, #7B5CF0 100%);
  color: var(--color-white);
  padding-block: var(--space-16);
}

.waitlist__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-8);
  flex-wrap: wrap;
}

.waitlist__copy h2 {
  font-size: clamp(var(--font-size-xl), 3vw, var(--font-size-3xl));
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-2);
}

.waitlist__copy p {
  font-size: var(--font-size-base);
  opacity: 0.85;
  max-width: 400px;
}

.waitlist-form {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
  align-items: flex-start;
  flex: 1;
  min-width: 280px;
  max-width: 480px;
}

.waitlist-form .form-input {
  flex: 1;
  min-width: 200px;
  background: rgba(255,255,255,0.15);
  border-color: rgba(255,255,255,0.3);
  color: var(--color-white);
}

.waitlist-form .form-input::placeholder {
  color: rgba(255,255,255,0.6);
}

.waitlist-form .form-input:focus {
  background: rgba(255,255,255,0.25);
  border-color: rgba(255,255,255,0.6);
  box-shadow: 0 0 0 3px rgba(255,255,255,0.15);
}

.waitlist-form #waitlist_error {
  color: #fde68a;
  width: 100%;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--color-text);
  color: #9CA3AF;
  padding-block: var(--space-12);
}

.footer__inner {
  text-align: center;
}

.footer__brand {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
  color: var(--color-white);
}

.footer__brand .logo-text { font-size: var(--font-size-lg); }

.footer__tagline {
  font-size: var(--font-size-sm);
  max-width: 480px;
  margin-inline: auto;
  margin-bottom: var(--space-4);
  line-height: 1.6;
}

.footer__legal {
  font-size: var(--font-size-xs);
  margin-bottom: var(--space-4);
}

.footer__legal a {
  color: #9CA3AF;
}

.footer__copyright {
  font-size: var(--font-size-xs);
  opacity: 0.5;
}

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
  .container { padding-inline: var(--space-4); }
  .section   { padding-block: var(--space-12); }

  .hero { padding-block: var(--space-16) var(--space-12); }
  .hero__actions { flex-direction: column; align-items: stretch; }
  .hero__actions .btn { text-align: center; }

  .differentiators {
    grid-template-columns: 1fr;
    gap: var(--space-5);
  }

  .waitlist__inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .waitlist-form {
    width: 100%;
    max-width: 100%;
    flex-direction: column;
  }

  .waitlist-form .btn { width: 100%; }
}

@media (max-width: 480px) {
  .hypothesis-cards { grid-template-columns: 1fr; }
  .feature-grid     { grid-template-columns: 1fr; }

  .radio-label, .checkbox-label {
    font-size: var(--font-size-sm);
  }
}

/* ---------- Utility ---------- */
[hidden] { display: none !important; }