/* ============================================
   MODERN AGE CALCULATOR - FACEBOOK THEME
   ============================================ */

/* CSS Variables for Easy Customization */
:root {
  --primary: #1877f2;
  --primary-dark: #166fe5;
  --primary-light: #3578e5;
  --success: #42b72a;
  --success-dark: #36a420;
  --warning: #f59e0b;
  --danger: #ef4444;
  --bg: #f0f2f5;
  --bg-card: #ffffff;
  --text: #1c1e21;
  --text-light: #65676b;
  --border: #e4e6eb;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
  --radius: 16px;
  --radius-lg: 20px;
  --radius-xl: 24px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset & Base Styles */
* {
  box-sizing: border-box;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
}

/* ============================================
   HEADING
   ============================================ */
.page-title {
  color: var(--text);
  font-weight: 700;
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  margin-bottom: 0.75rem;
  letter-spacing: -0.5px;
}

.page-subtitle {
  color: var(--text-light);
  font-size: 1.05rem;
  max-width: 640px;
  margin: 0 auto;
}

h1 {
  color: var(--text);
  font-weight: 700;
  font-size: 2rem;
  margin-bottom: 1rem;
  letter-spacing: -0.5px;
}

h2 {
  color: var(--text);
  font-weight: 700;
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

h3 {
  color: var(--text);
  font-weight: 600;
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

/* ============================================
   TOOL CARD
   ============================================ */
.tool-card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
  padding: 2rem;
  max-width: 800px;
  margin: 0 auto 2rem;
}

.input-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text);
  font-size: 0.9rem;
  text-align: left;
}

.optional-tag {
  font-weight: 400;
  color: var(--text-light);
  font-size: 0.8rem;
}

.form-hint {
  display: block;
  margin-top: 0.4rem;
  color: var(--text-light);
  font-size: 0.85rem;
  text-align: left;
}

.ad-slot {
  min-height: 280px;
}

.action-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-top: 1rem;
}

/* ============================================
   FORM INPUTS - Modern Design
   ============================================ */
body > .container .form-group {
  margin-bottom: 1.5rem;
}

body > .container .form-group label {
  display: block;
  margin-bottom: 0.75rem;
  font-weight: 600;
  color: var(--text);
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.tool-card .form-control,
#birthdate.form-control,
body > .container .form-control {
  border: 2px solid var(--border) !important;
  border-radius: var(--radius-lg);
  padding: 0.875rem 1.25rem;
  font-size: 1rem;
  transition: var(--transition);
  background: white;
  width: 100%;
  box-shadow: var(--shadow);
  text-align: center;
}

#birthdate.form-control,
body > .container .form-control:not(.tool-card .form-control) {
  max-width: 400px;
  margin: 0 auto;
}

#birthdate.form-control:focus,
body > .container .form-control:focus {
  outline: none !important;
  border-color: var(--primary) !important;
  box-shadow: 0 0 0 3px rgba(24, 119, 242, 0.1), var(--shadow-md);
  transform: translateY(-2px);
}

#birthdate.form-control:hover,
body > .container .form-control:hover {
  border-color: var(--primary-light);
}

/* ============================================
   BUTTONS - Modern & Interactive
   ============================================ */
.btn-outline-secondary {
  border-radius: 24px !important;
  padding: 0.875rem 2rem !important;
  font-weight: 600 !important;
  border: 2px solid var(--border) !important;
  transition: var(--transition);
}

.btn-outline-secondary:hover {
  background: var(--bg) !important;
  border-color: var(--primary) !important;
  color: var(--primary) !important;
}

.btn-success {
  background: var(--success) !important;
  border: none !important;
  border-radius: 24px !important;
  padding: 0.75rem 1.75rem !important;
  font-weight: 600 !important;
  transition: var(--transition);
}

.btn-success:hover {
  background: var(--success-dark) !important;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

#startButton.btn,
body > .container .btn-primary {
  background: var(--primary) !important;
  border: none !important;
  border-radius: 24px !important;
  padding: 0.875rem 2rem !important;
  font-weight: 600 !important;
  font-size: 1rem !important;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md) !important;
  color: white !important;
}

#startButton.btn::before,
body > .container .btn-primary::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

#startButton.btn:hover::before,
body > .container .btn-primary:hover::before {
  width: 300px;
  height: 300px;
}

#startButton.btn:hover,
body > .container .btn-primary:hover {
  transform: translateY(-2px) !important;
  box-shadow: var(--shadow-lg) !important;
  color: white !important;
  background: var(--primary-dark) !important;
}

#startButton.btn:active,
body > .container .btn-primary:active {
  transform: translateY(0) !important;
}

.btn-lg {
  padding: 1rem 2.5rem !important;
  font-size: 1.1rem !important;
}

/* ============================================
   ALERTS - Modern Styling
   ============================================ */
#alert.alert {
  border: none !important;
  border-radius: var(--radius-lg) !important;
  padding: 1rem 1.5rem !important;
  box-shadow: var(--shadow-md) !important;
  transition: var(--transition);
  animation: slideDown 0.3s ease-out;
  max-width: 600px;
  margin: 1.5rem auto;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.alert-primary {
  background: var(--primary) !important;
  color: white !important;
}

/* ============================================
   SPINNER
   ============================================ */
#spinner .spinner-border {
  width: 3rem;
  height: 3rem;
  border-width: 0.3em;
  border-color: var(--primary);
  border-right-color: transparent;
}

/* ============================================
   AGE DISPLAY SECTION
   ============================================ */
#result {
  animation: fadeInUp 0.6s ease-out;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}

.result-card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
  padding: 2rem;
}

.result-heading {
  text-align: center;
  margin-bottom: 1.25rem;
  font-size: 1.2rem;
}

.age-summary {
  text-align: center;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 0.5rem;
  line-height: 1.5;
}

.live-badge {
  text-align: center;
  font-size: 0.85rem;
  color: var(--success);
  font-weight: 600;
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
}

.live-dot {
  width: 8px;
  height: 8px;
  background: var(--success);
  border-radius: 50%;
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

.birthday-banner {
  background: linear-gradient(135deg, #f59e0b, #ef4444);
  color: white;
  padding: 1rem 1.5rem;
  border-radius: var(--radius-lg);
  text-align: center;
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 1.25rem;
  animation: fadeInUp 0.5s ease-out;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.age-box {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1.5rem;
}

.age-item {
  background: var(--bg);
  border: 2px solid var(--border);
  color: var(--text);
  padding: 1.25rem 1rem;
  border-radius: var(--radius-lg);
  text-align: center;
  transition: var(--transition);
  box-shadow: var(--shadow);
  flex: 1;
  min-width: 110px;
  max-width: 160px;
}

.age-icon {
  font-size: 1.5rem;
  margin-bottom: 0.25rem;
}

.age-label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-light);
}

.age-item:hover {
  transform: translateY(-4px) scale(1.05);
  border-color: var(--primary);
  box-shadow: var(--shadow-lg);
  background: var(--primary);
  color: white;
}

.age-value {
  display: block;
  font-size: 1.75rem;
  margin-top: 0.35rem;
  color: var(--primary);
  font-weight: 800;
  line-height: 1.2;
}

.age-item:hover .age-value {
  color: white;
}

/* Stats grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1rem;
}

.stat-item {
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  text-align: center;
  transition: var(--transition);
}

.stat-item:hover {
  border-color: var(--primary);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.stat-icon {
  display: block;
  font-size: 1.25rem;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.stat-label {
  display: block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.4px;
  color: var(--text-light);
  margin-bottom: 0.35rem;
}

.stat-value {
  display: block;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.3;
  word-break: break-word;
}

/* Milestones */
.milestones-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.milestone-item {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  transition: var(--transition);
}

.milestone-item:hover {
  border-color: var(--primary);
  transform: translateX(4px);
}

.milestone-label {
  font-weight: 700;
  color: var(--text);
}

.milestone-label i {
  color: var(--primary);
  margin-right: 0.35rem;
}

.milestone-meta {
  font-size: 0.85rem;
  color: var(--text-light);
}

.result-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

.copy-feedback {
  color: var(--success);
  font-weight: 600;
  font-size: 0.95rem;
  animation: fadeInUp 0.3s ease-out;
}

/* Feature list */
.feature-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 0.75rem;
  text-align: left;
}

.feature-list li {
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  color: var(--text);
  transition: var(--transition);
}

.feature-list li i {
  color: var(--primary);
  margin-right: 0.5rem;
  width: 1.25rem;
  text-align: center;
}

.feature-list li:hover {
  border-color: var(--primary);
  transform: translateX(4px);
}

/* ============================================
   SECTION CARDS
   ============================================ */
.section-card {
  background: var(--bg-card);
  padding: 0;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  margin: 2rem auto 3rem;
  max-width: 1000px;
  transition: var(--transition);
  animation: fadeInUp 0.6s ease-out;
  overflow: hidden;
  border: 1px solid var(--border);
}

.section-card + .section-card {
  margin-top: 3rem;
}

.section-card:last-child {
  margin-bottom: 2rem;
}

.section-card:hover {
  box-shadow: var(--shadow-xl);
  transform: translateY(-4px);
  border-color: var(--primary-light);
}

.section-card-header {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: white;
  padding: 2rem 2.5rem;
  text-align: center;
  margin: 0;
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
  position: relative;
  overflow: hidden;
}

.section-card-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s;
}

.section-card:hover .section-card-header::before {
  left: 100%;
}

.section-card-header h2 {
  color: white;
  font-weight: 700;
  font-size: 1.75rem;
  margin: 0;
  text-align: center;
  letter-spacing: -0.5px;
  position: relative;
  z-index: 1;
}

.section-card-body {
  padding: 2.5rem;
}

.section-card-body p {
  color: var(--text-light);
  line-height: 1.7;
  text-align: center;
  margin: 0;
  font-size: 1rem;
}

/* List Group Styling */
.list-group {
  border: none;
  border-radius: 0;
  overflow: visible;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.list-group-item {
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  color: var(--text);
  font-size: 1rem;
  transition: var(--transition);
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.list-group-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: 4px;
  height: 100%;
  background: var(--primary);
  transform: scaleY(0);
  transition: var(--transition);
}

.list-group-item:first-child {
  border-top: 2px solid var(--border);
  border-radius: var(--radius-lg);
}

.list-group-item:last-child {
  border-radius: var(--radius-lg);
}

.list-group-item:hover {
  background: var(--primary);
  color: white;
  transform: translateX(8px);
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.list-group-item:hover::before {
  transform: scaleY(1);
  background: var(--primary-dark);
}

/* ============================================
   ACCORDION - FAQ Section
   ============================================ */
body > .container .accordion {
  margin: 0;
}

.accordion-item {
  border: 1px solid var(--border) !important;
  border-radius: var(--radius) !important;
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.accordion-button {
  background: white !important;
  color: var(--text) !important;
  border: none !important;
  font-weight: 600;
  padding: 1rem 1.5rem;
  border-radius: var(--radius) !important;
}

.accordion-button:not(.collapsed) {
  background: var(--primary) !important;
  color: white !important;
  box-shadow: none !important;
}

.accordion-button:focus {
  box-shadow: 0 0 0 3px rgba(24, 119, 242, 0.1) !important;
}

.accordion-body {
  background: white;
  color: var(--text);
  padding: 1.5rem;
  line-height: 1.7;
}

/* ============================================
   BOOTSTRAP INFO COLOR OVERRIDE - Facebook Blue
   ============================================ */
.text-primary {
  color: var(--primary) !important;
}

.bg-primary {
  background-color: var(--primary) !important;
}

.border-primary {
  border-color: var(--primary) !important;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 768px) {
  :root {
    --radius: 14px;
    --radius-lg: 18px;
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.25rem;
  }

  h3 {
    font-size: 1.1rem;
  }

  .age-box {
    gap: 0.75rem;
  }

  .age-item {
    min-width: 100px;
    max-width: 150px;
    padding: 1.25rem 1rem;
    font-size: 1rem;
  }

  .age-value {
    font-size: 1.35rem;
  }

  .tool-card {
    padding: 1.25rem;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }

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

  .feature-list {
    grid-template-columns: 1fr;
  }

  #startButton.btn,
  body > .container .btn-primary {
    width: 100%;
    margin: 0.5rem 0;
  }

  .section-card {
    margin: 1.5rem 0;
  }

  .section-card-header {
    padding: 1.5rem 1.5rem;
  }

  .section-card-header h2 {
    font-size: 1.5rem;
  }

  .section-card-body {
    padding: 1.5rem;
  }

  .list-group {
    gap: 0.5rem;
  }

  .list-group-item {
    padding: 1rem 1.25rem;
    font-size: 0.9rem;
    border-radius: var(--radius-lg) !important;
    margin-bottom: 0 !important;
    border: 2px solid var(--border) !important;
  }

  .list-group-item:first-child {
    border-radius: var(--radius-lg) !important;
    border-top: 2px solid var(--border) !important;
  }

  .list-group-item:last-child {
    border-radius: var(--radius-lg) !important;
    margin-bottom: 0;
  }

  #birthdate.form-control,
  body > .container .form-control {
    max-width: 100%;
  }

  .section-card {
    margin: 1.5rem 0;
  }

  .section-card-header {
    padding: 1.5rem 1.5rem;
  }

  .section-card-header h2 {
    font-size: 1.5rem;
  }

  .list-group-item {
    padding: 1.25rem 1.5rem;
    font-size: 0.9rem;
    border-radius: var(--radius-lg) !important;
    margin-bottom: 0 !important;
    border: 2px solid var(--border) !important;
  }

  .list-group {
    gap: 0.75rem;
  }

  .list-group-item:first-child {
    border-radius: var(--radius-lg) !important;
    border-top: 2px solid var(--border) !important;
  }

  .list-group-item:last-child {
    border-radius: var(--radius-lg) !important;
    margin-bottom: 0;
  }
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* Container scoping - only affect main content containers */
body > .container {
  max-width: 1200px;
  margin: 0 auto;
  /* padding: 0 1rem; */
}