/* ========================================
   Estima ai — Modern UI
   ======================================== */

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

:root {
  --c-bg: #0a0a12;
  --c-surface: rgba(255, 255, 255, 0.04);
  --c-border: rgba(255, 255, 255, 0.08);
  --c-text: #e4e4ef;
  --c-text-muted: #8888a4;
  --c-accent: #7c5cfc;
  --c-accent-light: #a78bfa;
  --c-accent-glow: rgba(124, 92, 252, 0.35);
  --c-success: #34d399;
  --c-warning: #fbbf24;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font);
  background: var(--c-bg);
  color: var(--c-text);
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* ---- Background effects ---- */

.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 64px 64px;
  pointer-events: none;
  z-index: 0;
}

.bg-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(120px);
  pointer-events: none;
  z-index: 0;
}

.bg-glow--1 {
  width: 600px;
  height: 600px;
  background: var(--c-accent-glow);
  top: -200px;
  right: -100px;
  opacity: 0.5;
}

.bg-glow--2 {
  width: 500px;
  height: 500px;
  background: rgba(52, 211, 153, 0.15);
  bottom: -200px;
  left: -150px;
  opacity: 0.4;
}

/* ---- Layout ---- */

.container {
  position: relative;
  z-index: 1;
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem 1.25rem;
}

/* ---- Screens ---- */

.screen {
  width: 100%;
  max-width: 560px;
  display: none;
  flex-direction: column;
  align-items: center;
  text-align: center;
  animation: fadeUp 0.5s ease-out;
}

.screen--visible {
  display: flex;
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---- Badge pill ---- */

.badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 1rem;
  border-radius: 999px;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  color: var(--c-text-muted);
  font-size: 0.8125rem;
  font-weight: 500;
  margin-bottom: 1.5rem;
  letter-spacing: 0.01em;
}

/* ---- Title ---- */

.title {
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  font-weight: 900;
  line-height: 1.1;
  margin-bottom: 1rem;
  letter-spacing: -0.03em;
}

.title__accent {
  background: linear-gradient(135deg, var(--c-accent-light), var(--c-accent), #e879f9);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* ---- Subtitle ---- */

.subtitle {
  font-size: 1.0625rem;
  color: var(--c-text-muted);
  line-height: 1.6;
  max-width: 440px;
  margin-bottom: 2rem;
}

.subtitle__methods {
  display: block;
  font-size: 0.875rem;
  margin-top: 0.25rem;
  opacity: 0.7;
}

/* ---- Card ---- */

.card {
  width: 100%;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.card__label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--c-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 1rem;
  text-align: left;
}

/* ---- Toggle group ---- */

.toggle-group {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.toggle-option {
  display: flex;
  align-items: center;
  gap: 0.875rem;
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--c-border);
  background: transparent;
  cursor: pointer;
  transition: var(--transition);
  text-align: left;
}

.toggle-option input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.toggle-option:hover {
  border-color: rgba(124, 92, 252, 0.3);
  background: rgba(124, 92, 252, 0.05);
}

.toggle-option--active {
  border-color: var(--c-accent);
  background: rgba(124, 92, 252, 0.08);
  box-shadow: 0 0 20px rgba(124, 92, 252, 0.1);
}

.toggle-option__icon {
  font-size: 1.75rem;
  line-height: 1;
  flex-shrink: 0;
}

.toggle-option__text {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}

.toggle-option__text strong {
  font-weight: 600;
  font-size: 0.9375rem;
}

.toggle-option__text small {
  font-size: 0.8125rem;
  color: var(--c-text-muted);
}

/* ---- Primary Button ---- */

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.9375rem 2rem;
  border: none;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--c-accent), #9333ea);
  color: #fff;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent, rgba(255,255,255,0.15));
  opacity: 0;
  transition: var(--transition);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(124, 92, 252, 0.4);
}

.btn-primary:hover::before {
  opacity: 1;
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-primary__icon {
  font-size: 1.25rem;
  transition: transform 0.2s ease;
}

.btn-primary:hover .btn-primary__icon {
  transform: translateX(4px);
}

/* ---- Footnote ---- */

.footnote {
  margin-top: 1.25rem;
  font-size: 0.75rem;
  color: var(--c-text-muted);
  opacity: 0.5;
  font-style: italic;
}

/* ---- Back button ---- */

.btn-back {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 1rem;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
  background: var(--c-surface);
  color: var(--c-text-muted);
  font-family: var(--font);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  margin-bottom: 2rem;
}

.btn-back:hover {
  color: var(--c-text);
  border-color: rgba(255,255,255,0.15);
}

/* ---- Result screen ---- */

.result-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.result-subtitle {
  color: var(--c-text-muted);
  font-size: 0.9375rem;
  margin-bottom: 2rem;
}

/* ---- Countdown ---- */

.countdown {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 2rem;
}

.countdown__item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.375rem;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  padding: 1.25rem 1rem;
  min-width: 72px;
  backdrop-filter: blur(8px);
}

.countdown__number {
  font-size: clamp(1.75rem, 5vw, 2.5rem);
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  background: linear-gradient(135deg, #fff, var(--c-accent-light));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
}

.countdown__label {
  font-size: 0.6875rem;
  font-weight: 500;
  color: var(--c-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.countdown__separator {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--c-text-muted);
  opacity: 0.4;
  padding-bottom: 1.25rem;
}

/* ---- Alert box ---- */

.alert-box {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  width: 100%;
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  background: rgba(251, 191, 36, 0.06);
  border: 1px solid rgba(251, 191, 36, 0.15);
  text-align: left;
  margin-bottom: 1.5rem;
}

.alert-box__icon {
  font-size: 1.25rem;
  flex-shrink: 0;
  line-height: 1.5;
}

.alert-box p {
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--c-warning);
}

/* ---- Fun facts ---- */

.fun-facts {
  font-size: 0.8125rem;
  color: var(--c-text-muted);
  font-style: italic;
  min-height: 1.5em;
}

/* ---- Footer ---- */

.footer {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  padding: 1.25rem;
  font-size: 0.8125rem;
  color: var(--c-text-muted);
  opacity: 0.6;
}

.footer a {
  color: var(--c-text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

.footer a:hover {
  color: var(--c-text);
}

/* ---- Responsive ---- */

@media (max-width: 480px) {
  .container {
    padding: 1.5rem 1rem;
  }

  .card {
    padding: 1.25rem;
  }

  .countdown {
    gap: 0.25rem;
  }

  .countdown__item {
    min-width: 60px;
    padding: 1rem 0.625rem;
  }

  .countdown__separator {
    font-size: 1.125rem;
  }

  .toggle-option {
    padding: 0.875rem 1rem;
  }
}

/* ---- Animations ---- */

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.countdown__separator {
  animation: pulse 1.5s ease-in-out infinite;
}

/* Loading state */
.btn-primary--loading {
  pointer-events: none;
}

.btn-primary--loading .btn-primary__text::after {
  content: '';
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255,255,255,0.3);
  border-top-color: #fff;
  border-radius: 50%;
  margin-left: 0.5rem;
  vertical-align: middle;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ---- SEO content (visible to crawlers, subtle for users) ---- */

.seo-content {
  width: 100%;
  max-width: 480px;
  text-align: left;
  margin-bottom: 1.5rem;
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-md);
  background: var(--c-surface);
  border: 1px solid var(--c-border);
}

.seo-content h2 {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--c-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.5rem;
  margin-top: 0.75rem;
}

.seo-content h2:first-child {
  margin-top: 0;
}

.seo-content p {
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--c-text-muted);
  opacity: 0.8;
}

/* ---- Screen reader only ---- */

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}