/* ==========================================================================
   Age Calculator - Modern, Responsive CSS Stylesheet
   Theme: Purple & Blue Gradient Palette, Rounded Cards, Fluid Typography
   ========================================================================== */

:root {
  /* Color Palette - Light Theme */
  --color-bg-gradient-start: #4f46e5;
  --color-bg-gradient-mid: #7c3aed;
  --color-bg-gradient-end: #2563eb;

  --color-card-bg: #ffffff;
  --color-card-border: rgba(255, 255, 255, 0.6);
  --color-card-shadow: 0 25px 60px -15px rgba(30, 27, 75, 0.35), 0 0 0 1px rgba(255, 255, 255, 0.4);

  --color-text-primary: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;

  --color-primary: #6366f1;
  --color-primary-hover: #4f46e5;
  --color-primary-active: #4338ca;
  --color-primary-glow: rgba(99, 102, 241, 0.35);

  --color-input-bg: #f8fafc;
  --color-input-border: #cbd5e1;
  --color-input-focus-border: #6366f1;

  --color-box-bg: #f8faff;
  --color-box-border: #e0e7ff;
  --color-box-shadow: 0 4px 16px rgba(99, 102, 241, 0.08);

  --color-box-years-accent: #6366f1;
  --color-box-months-accent: #8b5cf6;
  --color-box-days-accent: #3b82f6;

  --color-stats-bg: #f1f5f9;
  --color-stats-border: #e2e8f0;

  --color-error-bg: #fef2f2;
  --color-error-border: #fecaca;
  --color-error-text: #b91c1c;

  --color-banner-bg: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
  --color-banner-border: #f59e0b;
  --color-banner-text: #92400e;

  --color-toast-bg: #1e1b4b;
  --color-toast-text: #ffffff;

  --color-nav-pill-bg: rgba(255, 255, 255, 0.2);
  --color-nav-pill-border: rgba(255, 255, 255, 0.3);
  --color-nav-pill-text: #ffffff;

  --color-footer-text: rgba(255, 255, 255, 0.9);

  /* Typography & Transitions */
  --font-family: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
  --transition-slow: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  --radius-card: 28px;
  --radius-box: 18px;
  --radius-btn: 14px;
}

/* ==========================================================================
   Dark Theme Overrides
   ========================================================================== */
[data-theme="dark"] {
  --color-bg-gradient-start: #090d16;
  --color-bg-gradient-mid: #10172a;
  --color-bg-gradient-end: #0f172a;

  --color-card-bg: #131b2e;
  --color-card-border: rgba(255, 255, 255, 0.08);
  --color-card-shadow: 0 30px 70px -15px rgba(0, 0, 0, 0.7), 0 0 0 1px rgba(255, 255, 255, 0.07);

  --color-text-primary: #f8fafc;
  --color-text-secondary: #94a3b8;
  --color-text-muted: #64748b;

  --color-primary: #818cf8;
  --color-primary-hover: #6366f1;
  --color-primary-active: #4f46e5;
  --color-primary-glow: rgba(129, 140, 248, 0.35);

  --color-input-bg: #0f172a;
  --color-input-border: #334155;
  --color-input-focus-border: #818cf8;

  --color-box-bg: #1e293b;
  --color-box-border: #334155;
  --color-box-shadow: 0 4px 20px rgba(0, 0, 0, 0.35);

  --color-box-years-accent: #818cf8;
  --color-box-months-accent: #a78bfa;
  --color-box-days-accent: #60a5fa;

  --color-stats-bg: #0f172a;
  --color-stats-border: #1e293b;

  --color-error-bg: #450a0a;
  --color-error-border: #7f1d1d;
  --color-error-text: #fca5a5;

  --color-banner-bg: linear-gradient(135deg, #451a03 0%, #78350f 100%);
  --color-banner-border: #b45309;
  --color-banner-text: #fef3c7;

  --color-toast-bg: #1e293b;
  --color-toast-text: #f8fafc;

  --color-nav-pill-bg: rgba(255, 255, 255, 0.08);
  --color-nav-pill-border: rgba(255, 255, 255, 0.12);
  --color-nav-pill-text: #e2e8f0;

  --color-footer-text: #94a3b8;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  align-items: center;
  background: linear-gradient(
    135deg,
    var(--color-bg-gradient-start) 0%,
    var(--color-bg-gradient-mid) 50%,
    var(--color-bg-gradient-end) 100%
  );
  background-attachment: fixed;
  color: var(--color-text-primary);
  line-height: 1.5;
  position: relative;
  overflow-x: hidden;
  padding: 1.5rem 1rem 2.5rem;
  transition: background var(--transition-slow);
}

/* Background Ambient Glow Orbs */
.ambient-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(100px);
  pointer-events: none;
  z-index: 0;
  opacity: 0.6;
}

.glow-1 {
  width: 450px;
  height: 450px;
  top: -120px;
  left: -80px;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.45) 0%, transparent 70%);
}

.glow-2 {
  width: 420px;
  height: 420px;
  bottom: -100px;
  right: -60px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.45) 0%, transparent 70%);
}

/* Container */
.app-container {
  width: 100%;
  max-width: 580px;
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  z-index: 1;
}

/* ==========================================================================
   Top Navigation & Theme Toggle
   ========================================================================== */
.top-nav {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.25rem;
}

.brand-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.85rem;
  background: var(--color-nav-pill-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--color-nav-pill-border);
  border-radius: 9999px;
  font-size: 0.775rem;
  font-weight: 600;
  color: var(--color-nav-pill-text);
  letter-spacing: 0.02em;
}

.brand-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 10px #10b981;
}

.nav-actions {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.download-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.85rem;
  background: var(--color-nav-pill-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--color-nav-pill-border);
  border-radius: 9999px;
  font-size: 0.775rem;
  font-weight: 700;
  color: var(--color-nav-pill-text);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.download-pill:hover {
  transform: translateY(-1px);
  background: rgba(255, 255, 255, 0.28);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.download-pill:focus-visible {
  outline: 2px solid #ffffff;
  outline-offset: 2px;
}

.download-icon {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.85rem;
  background: var(--color-nav-pill-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--color-nav-pill-border);
  border-radius: 9999px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-nav-pill-text);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  transform: translateY(-1px);
  background: rgba(255, 255, 255, 0.28);
}

.theme-toggle:focus-visible {
  outline: 2px solid #ffffff;
  outline-offset: 2px;
}

.theme-toggle svg {
  width: 16px;
  height: 16px;
}

/* Toggle Sun/Moon display depending on theme */
[data-theme="light"] .sun-icon {
  display: none;
}
[data-theme="light"] .moon-icon {
  display: block;
}

[data-theme="dark"] .sun-icon {
  display: block;
}
[data-theme="dark"] .moon-icon {
  display: none;
}

/* ==========================================================================
   Main Calculator Card
   ========================================================================== */
.calculator-card {
  width: 100%;
  background: var(--color-card-bg);
  border-radius: var(--radius-card);
  border: 1px solid var(--color-card-border);
  box-shadow: var(--color-card-shadow);
  padding: 1.75rem 1.75rem;
  transition: background var(--transition-slow), border-color var(--transition-slow), box-shadow var(--transition-slow);
  animation: cardFadeIn 0.5s ease-out;
}

@keyframes cardFadeIn {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Header */
.app-header {
  text-align: center;
  margin-bottom: 1.35rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.icon-badge {
  width: 46px;
  height: 46px;
  border-radius: 14px;
  background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 0.75rem;
  box-shadow: 0 8px 20px var(--color-primary-glow);
  transition: transform var(--transition-fast);
}

.icon-badge:hover {
  transform: scale(1.05) rotate(-3deg);
}

.icon-badge svg {
  width: 24px;
  height: 24px;
}

.app-title {
  font-size: 1.65rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--color-text-primary);
  margin-bottom: 0.25rem;
}

.app-subtitle {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  font-weight: 500;
}

/* ==========================================================================
   Date of Birth Input & Form
   ========================================================================== */
.calculator-form {
  margin-bottom: 1.5rem;
}

.input-group {
  margin-bottom: 1.5rem;
}

.label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.55rem;
}

.input-label {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-text-primary);
  cursor: pointer;
}

.label-icon {
  width: 17px;
  height: 17px;
  color: var(--color-primary);
}

.input-hint {
  font-size: 0.775rem;
  color: var(--color-text-muted);
  font-weight: 500;
}

.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.date-input {
  width: 100%;
  padding: 0.95rem 1.15rem;
  background: var(--color-input-bg);
  border: 1.5px solid var(--color-input-border);
  border-radius: var(--radius-btn);
  font-family: var(--font-family);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-text-primary);
  outline: none;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.date-input:focus {
  border-color: var(--color-input-focus-border);
  box-shadow: 0 0 0 3.5px var(--color-primary-glow);
  background: var(--color-card-bg);
}

/* Custom Calendar Icon picker styling */
.date-input::-webkit-calendar-picker-indicator {
  cursor: pointer;
  opacity: 0.75;
  filter: invert(0.3);
  transition: opacity var(--transition-fast), transform var(--transition-fast);
}

[data-theme="dark"] .date-input::-webkit-calendar-picker-indicator {
  filter: invert(0.9);
}

.date-input::-webkit-calendar-picker-indicator:hover {
  opacity: 1;
  transform: scale(1.1);
}

/* Validation Message */
.validation-message {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.65rem;
  padding: 0.6rem 0.85rem;
  background: var(--color-error-bg);
  border: 1px solid var(--color-error-border);
  border-radius: 10px;
  color: var(--color-error-text);
  font-size: 0.85rem;
  font-weight: 600;
  animation: shake 0.35s ease-in-out;
}

.validation-message.hidden {
  display: none;
}

.error-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%, 60% { transform: translateX(-6px); }
  40%, 80% { transform: translateX(6px); }
}

/* Calculate Button */
.calculate-btn {
  width: 100%;
  padding: 1rem 1.5rem;
  background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #3b82f6 100%);
  background-size: 200% 200%;
  border: none;
  border-radius: var(--radius-btn);
  color: #ffffff;
  font-family: var(--font-family);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  cursor: pointer;
  box-shadow: 0 10px 25px -5px var(--color-primary-glow);
  transition: all var(--transition-normal);
  display: flex;
  align-items: center;
  justify-content: center;
}

.calculate-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 28px -5px var(--color-primary-glow);
  background-position: right center;
}

.calculate-btn:active {
  transform: translateY(0);
  box-shadow: 0 6px 16px -3px var(--color-primary-glow);
}

.calculate-btn:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
}

.btn-content {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
}

.btn-icon {
  width: 20px;
  height: 20px;
}

/* ==========================================================================
   Birthday Celebration Banner
   ========================================================================== */
.birthday-banner {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  background: var(--color-banner-bg);
  border: 1px solid var(--color-banner-border);
  border-radius: var(--radius-box);
  padding: 0.9rem 1.15rem;
  margin-bottom: 1.5rem;
  color: var(--color-banner-text);
  animation: bounceIn 0.5s ease-out;
}

.birthday-banner.hidden {
  display: none;
}

.banner-emoji {
  font-size: 1.6rem;
  flex-shrink: 0;
}

.banner-text {
  display: flex;
  flex-direction: column;
  font-size: 0.875rem;
  line-height: 1.35;
}

.banner-text strong {
  font-size: 1rem;
}

@keyframes bounceIn {
  0% { transform: scale(0.9); opacity: 0; }
  60% { transform: scale(1.03); opacity: 1; }
  100% { transform: scale(1); }
}

/* ==========================================================================
   Results Section
   ========================================================================== */
.results-section {
  border-top: 1px solid var(--color-stats-border);
  padding-top: 1.25rem;
  animation: slideFadeDown 0.4s ease-out;
}

.results-section.hidden {
  display: none;
}

@keyframes slideFadeDown {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.results-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.results-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--color-text-primary);
  letter-spacing: -0.015em;
}

.results-summary-badge {
  font-size: 0.8rem;
  font-weight: 700;
  padding: 0.35rem 0.75rem;
  border-radius: 9999px;
  background: var(--color-box-bg);
  border: 1px solid var(--color-box-border);
  color: var(--color-primary);
}

/* 3 Separate Result Boxes Grid */
.result-boxes-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
  margin-bottom: 1.15rem;
}

.result-box {
  background: var(--color-box-bg);
  border: 1.5px solid var(--color-box-border);
  border-radius: var(--radius-box);
  box-shadow: var(--color-box-shadow);
  padding: 0.95rem 0.65rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  position: relative;
  overflow: hidden;
  transition: transform var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.result-box:hover {
  transform: translateY(-3px);
  border-color: var(--color-primary);
}

/* Staggered entry animation on calculate */
.result-box.animating {
  animation: boxCardPop 0.5s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.result-box.box-months.animating {
  animation-delay: 0.08s;
}

.result-box.box-days.animating {
  animation-delay: 0.16s;
}

/* Subtle Shimmer Sweep on calculate */
.result-box::after {
  content: '';
  position: absolute;
  top: 0;
  left: -120%;
  width: 80%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.45) 50%,
    transparent 100%
  );
  pointer-events: none;
  opacity: 0;
}

[data-theme="dark"] .result-box::after {
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.12) 50%,
    transparent 100%
  );
}

.result-box.animating::after {
  animation: shimmerPass 0.85s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* Top accent bars for each box */
.result-box::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
}

.box-years::before {
  background: linear-gradient(90deg, #6366f1, #818cf8);
}
.box-months::before {
  background: linear-gradient(90deg, #8b5cf6, #c084fc);
}
.box-days::before {
  background: linear-gradient(90deg, #3b82f6, #60a5fa);
}

.box-badge {
  font-size: 0.7rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin-bottom: 0.25rem;
}

.number-wrapper {
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.result-number {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  display: inline-block;
  transform-origin: center center;
  transition: transform 0.15s ease, filter 0.15s ease;
  will-change: transform;
}

/* Smooth Count Up States */
.result-number.is-counting {
  transform: scale(1.05);
  filter: drop-shadow(0 2px 8px var(--color-primary-glow));
}

.result-number.counting-complete {
  animation: numberPulsePop 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes boxCardPop {
  0% {
    opacity: 0.6;
    transform: translateY(8px) scale(0.97);
  }
  100% {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes shimmerPass {
  0% {
    left: -120%;
    opacity: 0.8;
  }
  100% {
    left: 200%;
    opacity: 0;
  }
}

@keyframes numberPulsePop {
  0% {
    transform: scale(1.14);
  }
  50% {
    transform: scale(0.97);
  }
  100% {
    transform: scale(1);
  }
}

.box-years .result-number {
  color: var(--color-box-years-accent);
}
.box-months .result-number {
  color: var(--color-box-months-accent);
}
.box-days .result-number {
  color: var(--color-box-days-accent);
}

.box-label {
  font-size: 0.775rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-top: 0.25rem;
}

/* ==========================================================================
   Additional Stats Card
   ========================================================================== */
.stats-card {
  background: var(--color-stats-bg);
  border: 1px solid var(--color-stats-border);
  border-radius: var(--radius-box);
  padding: 0.95rem 1.15rem;
  margin-bottom: 1.15rem;
}

.stat-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.85rem;
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.stat-label {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.725rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
}

.stat-icon {
  width: 14px;
  height: 14px;
  color: var(--color-primary);
}

.stat-value {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-text-primary);
  word-break: break-word;
}

.stat-value.highlight {
  color: var(--color-primary);
}

.stat-value.zodiac-value {
  color: var(--color-primary);
  font-weight: 700;
}

.stat-divider {
  height: 1px;
  background: var(--color-stats-border);
  margin: 0.65rem 0;
}

/* ==========================================================================
   Life Milestones Section
   ========================================================================== */
.milestones-section {
  margin-bottom: 1.15rem;
}

.milestones-header {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  margin-bottom: 0.75rem;
  text-align: left;
}

.milestones-title {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.825rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-primary);
}

.milestone-title-icon {
  width: 15px;
  height: 15px;
  stroke: var(--color-primary);
}

.milestones-subtitle {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.milestones-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.milestone-card {
  background: var(--color-box-bg);
  border: 1px solid var(--color-box-border);
  border-radius: var(--radius-box);
  padding: 0.85rem 0.95rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  text-align: left;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.milestone-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(99, 102, 241, 0.12);
}

.milestone-badge-row {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.milestone-icon-tag {
  font-size: 1rem;
  line-height: 1;
}

.milestone-name {
  font-size: 0.785rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.milestone-date {
  font-size: 0.875rem;
  font-weight: 800;
  color: var(--color-primary);
}

.milestone-countdown {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-text-secondary);
}

.progress-wrap {
  margin-top: 0.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.progress-track {
  width: 100%;
  height: 6px;
  background: var(--color-stats-border);
  border-radius: 9999px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), #a855f7);
  border-radius: 9999px;
  transition: width 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.progress-label {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-align: right;
}

.milestone-pill-wrap {
  margin-top: 0.3rem;
}

.milestone-pill {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.2rem 0.6rem;
  border-radius: 9999px;
  background: rgba(99, 102, 241, 0.12);
  color: var(--color-primary);
}

/* ==========================================================================
   AdMob / AdSense Banner Container
   Configured for Google AdSense & AdMob (Responsive & 320x50 Banner)
   ========================================================================== */
.admob-container {
  margin-bottom: 1.15rem;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
}

.admob-label {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  opacity: 0.75;
  text-transform: uppercase;
}

.admob-slot {
  width: 100%;
  max-width: 468px;
  min-height: 52px;
  border: 1px dashed var(--color-input-border);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(99, 102, 241, 0.04);
  overflow: hidden;
  position: relative;
  transition: all var(--transition-fast);
}

.admob-slot:hover {
  border-color: var(--color-primary);
  background: rgba(99, 102, 241, 0.07);
}

.admob-placeholder-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.65rem 1rem;
  color: var(--color-text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  text-align: center;
}

.admob-icon {
  font-size: 0.95rem;
}

.admob-text {
  font-size: 0.75rem;
  line-height: 1.2;
}

/* ==========================================================================
   Action Buttons (Copy, Share, Reset)
   ========================================================================== */
.action-buttons-group {
  display: grid;
  grid-template-columns: 1.2fr 1.2fr 0.9fr;
  gap: 0.75rem;
}

.action-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-btn);
  font-family: var(--font-family);
  font-size: 0.875rem;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1px solid var(--color-input-border);
  background: var(--color-card-bg);
  color: var(--color-text-primary);
}

.action-btn:hover {
  transform: translateY(-1.5px);
  border-color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

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

.action-btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.action-btn.copy-btn:hover {
  background: var(--color-box-bg);
  color: var(--color-primary);
}

.action-btn.share-btn:hover {
  background: var(--color-box-bg);
  color: var(--color-primary);
}

.action-btn.reset-btn {
  color: var(--color-text-muted);
}

.action-btn.reset-btn:hover {
  background: var(--color-error-bg);
  border-color: var(--color-error-border);
  color: var(--color-error-text);
}

.action-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.action-icon.hidden {
  display: none;
}

/* ==========================================================================
   Toast Feedback Notification
   ========================================================================== */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--color-toast-bg);
  color: var(--color-toast-text);
  padding: 0.75rem 1.35rem;
  border-radius: 9999px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
  font-size: 0.875rem;
  font-weight: 600;
  z-index: 1000;
  transition: all var(--transition-normal);
  animation: toastPop 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.toast.hidden {
  opacity: 0;
  pointer-events: none;
  transform: translate(-50%, 15px);
}

.toast-icon {
  width: 18px;
  height: 18px;
  color: #10b981;
}

@keyframes toastPop {
  from {
    opacity: 0;
    transform: translate(-50%, 20px);
  }
  to {
    opacity: 1;
    transform: translate(-50%, 0);
  }
}

/* ==========================================================================
   Footer
   ========================================================================== */
.app-footer {
  margin-top: 1.75rem;
  text-align: center;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-footer-text);
  letter-spacing: 0.02em;
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */
@media (max-width: 600px) {
  body {
    padding: 1rem 0.75rem;
  }

  .calculator-card {
    padding: 1.75rem 1.25rem;
    border-radius: 22px;
  }

  .app-title {
    font-size: 1.55rem;
  }

  .result-boxes-grid {
    gap: 0.65rem;
  }

  .result-box {
    padding: 1rem 0.5rem;
    border-radius: 14px;
  }

  .result-number {
    font-size: 1.95rem;
  }

  .box-label {
    font-size: 0.725rem;
  }

  .stat-row {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  .milestones-grid {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  .action-buttons-group {
    grid-template-columns: 1fr 1fr;
  }

  .action-btn.reset-btn {
    grid-column: span 2;
  }
}

@media (max-width: 380px) {
  .result-boxes-grid {
    grid-template-columns: 1fr;
  }

  .action-buttons-group {
    grid-template-columns: 1fr;
  }

  .action-btn.reset-btn {
    grid-column: span 1;
  }
}

/* Accessibility: Respect Reduced Motion Preferences */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .result-box.animating,
  .result-number.counting-complete {
    animation: none !important;
  }
}