/* ============================================
   SU İHTİYACI HESAPLAYICI - STYLES
   Premium Design System v2.0
   ============================================ */

/* CSS Variables - Theme System */
:root {
  --bg: #ffffff;
  --bg-secondary: #f0f4f8;
  --bg-tertiary: #e2e8f0;
  --card: #ffffff;
  --text: #1a202c;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --border: #e2e8f0;
  --border-light: #f1f5f9;
  --accent: #0066ff;
  --accent-hover: #0052cc;
  --accent-light: #e6f0ff;
  --accent2: #00b4d8;
  --accent3: #06d6a0;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;
  --shadow: rgba(0, 0, 0, 0.06);
  --shadow-md: rgba(0, 0, 0, 0.1);
  --shadow-lg: rgba(0, 0, 0, 0.15);
  --shadow-accent: rgba(0, 102, 255, 0.2);
  --radius: 16px;
  --radius-sm: 10px;
  --radius-xs: 6px;
  --radius-full: 9999px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --gradient-primary: linear-gradient(135deg, #0066ff 0%, #00b4d8 100%);
  --gradient-warm: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%);
  --gradient-cool: linear-gradient(135deg, #06d6a0 0%, #0066ff 100%);
  --gradient-subtle: linear-gradient(135deg, #f0f4f8 0%, #e2e8f0 100%);
}

[data-theme="dark"] {
  --bg: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --card: #1e293b;
  --text: #f1f5f9;
  --text-muted: #94a3b8;
  --text-light: #64748b;
  --border: #334155;
  --border-light: #1e293b;
  --accent-light: #172554;
  --shadow: rgba(0, 0, 0, 0.3);
  --shadow-md: rgba(0, 0, 0, 0.4);
  --shadow-lg: rgba(0, 0, 0, 0.5);
  --shadow-accent: rgba(0, 102, 255, 0.3);
  --gradient-subtle: linear-gradient(135deg, #1e293b 0%, #334155 100%);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  transition: background var(--transition), color var(--transition);
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  height: auto;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-narrow {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-wide {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================
   HEADER
   ============================================ */
.header {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  padding: 12px 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: all var(--transition);
}

[data-theme="dark"] .header {
  background: rgba(15, 23, 42, 0.85);
}

.header.scrolled {
  box-shadow: 0 4px 20px var(--shadow-md);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}

.logo {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--accent);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
  letter-spacing: -0.02em;
}

.logo-icon {
  font-size: 1.8rem;
  filter: drop-shadow(0 2px 4px rgba(0, 102, 255, 0.3));
}

.nav {
  display: flex;
  gap: 8px;
  align-items: center;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent);
  background: var(--accent-light);
}

.theme-toggle {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  cursor: pointer;
  font-size: 1.1rem;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  transform: rotate(15deg);
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 1.3rem;
  cursor: pointer;
  color: var(--text);
  padding: 8px 12px;
  transition: all var(--transition);
}

.mobile-menu-btn:hover {
  background: var(--accent);
  color: white;
}

@media (max-width: 768px) {
  .mobile-menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
  }
  
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--card);
    flex-direction: column;
    padding: 16px;
    border-bottom: 1px solid var(--border);
    box-shadow: 0 12px 40px var(--shadow-lg);
    gap: 4px;
  }
  
  .nav.active {
    display: flex;
  }

  .nav-link {
    width: 100%;
    padding: 12px 16px;
  }
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
  background: var(--gradient-primary);
  color: white;
  padding: 80px 24px 100px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(ellipse at 30% 50%, rgba(255,255,255,0.1) 0%, transparent 60%);
  animation: heroShimmer 8s ease-in-out infinite;
}

@keyframes heroShimmer {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(5%, 5%); }
}

.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  padding: 8px 20px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 24px;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.hero h1 {
  font-size: 3.2rem;
  margin-bottom: 20px;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
}

.hero p {
  font-size: 1.25rem;
  opacity: 0.92;
  max-width: 600px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 20px;
}

.hero-stat {
  text-align: center;
}

.hero-stat-value {
  font-size: 2.2rem;
  font-weight: 800;
  display: block;
  line-height: 1.2;
}

.hero-stat-label {
  font-size: 0.85rem;
  opacity: 0.8;
  font-weight: 500;
}

.hero-wave {
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  overflow: hidden;
  line-height: 0;
}

.hero-wave svg {
  display: block;
  width: 100%;
  height: 60px;
}

.hero-wave svg path {
  fill: var(--bg);
}

/* ============================================
   SECTIONS
   ============================================ */
.section {
  padding: 80px 24px;
}

.section-sm {
  padding: 48px 24px;
}

.section-alt {
  background: var(--bg-secondary);
}

.section-title {
  font-size: 2.2rem;
  margin-bottom: 12px;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1.15rem;
  margin-bottom: 48px;
  line-height: 1.7;
}

.section-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--accent-light);
  color: var(--accent);
  padding: 6px 16px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 16px;
}

/* ============================================
   CARDS
   ============================================ */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: 0 1px 3px var(--shadow);
  transition: all var(--transition);
  display: block;
}

.card:hover {
  box-shadow: 0 8px 30px var(--shadow-md);
  transform: translateY(-4px);
  border-color: var(--accent);
}

.card-title {
  font-size: 1.3rem;
  margin-bottom: 10px;
  font-weight: 700;
  line-height: 1.3;
}

.card-text {
  color: var(--text-muted);
  line-height: 1.7;
  font-size: 0.95rem;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 16px;
  font-size: 0.85rem;
  color: var(--text-light);
}

.card-meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.card-tag {
  display: inline-block;
  background: var(--accent-light);
  color: var(--accent);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 12px;
}

/* Featured Card */
.card-featured {
  background: var(--gradient-primary);
  color: white;
  border: none;
  position: relative;
  overflow: hidden;
}

.card-featured::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -50%;
  width: 100%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
}

.card-featured .card-text {
  color: rgba(255, 255, 255, 0.85);
}

.card-featured:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px var(--shadow-accent);
}

/* ============================================
   GRID SYSTEM
   ============================================ */
.grid {
  display: grid;
  gap: 24px;
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.grid-5 {
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

/* ============================================
   BENEFITS SECTION
   ============================================ */
.benefit-card {
  text-align: center;
  padding: 32px 24px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}

.benefit-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px var(--shadow-md);
  border-color: var(--accent);
}

.benefit-icon {
  width: 72px;
  height: 72px;
  background: var(--accent-light);
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  margin: 0 auto 20px;
  transition: all var(--transition);
}

.benefit-card:hover .benefit-icon {
  background: var(--gradient-primary);
  transform: scale(1.1) rotate(5deg);
}

.benefit-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.benefit-text {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ============================================
   HOW IT WORKS
   ============================================ */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 32px;
  position: relative;
}

.step {
  text-align: center;
  position: relative;
}

.step-number {
  width: 56px;
  height: 56px;
  background: var(--gradient-primary);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  font-weight: 800;
  margin: 0 auto 16px;
  box-shadow: 0 4px 15px var(--shadow-accent);
}

.step-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-text {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ============================================
   WATER TRACKER
   ============================================ */
.tracker {
  background: var(--card);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  text-align: center;
  max-width: 480px;
  margin: 0 auto;
}

.tracker-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.tracker-subtitle {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 24px;
}

.tracker-visual {
  position: relative;
  width: 200px;
  height: 200px;
  margin: 0 auto 24px;
}

.tracker-circle {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: var(--bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

.tracker-wave {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  background: var(--gradient-primary);
  transition: height 0.8s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: 0 0 50% 50%;
}

.tracker-value {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent);
  position: relative;
  z-index: 2;
  line-height: 1;
}

.tracker-unit {
  font-size: 0.85rem;
  color: var(--text-muted);
  position: relative;
  z-index: 2;
  margin-top: 4px;
}

.tracker-buttons {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.tracker-btn {
  padding: 10px 20px;
  border: 2px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--bg);
  color: var(--text);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--transition);
}

.tracker-btn:hover {
  border-color: var(--accent);
  background: var(--accent-light);
  color: var(--accent);
  transform: scale(1.05);
}

.tracker-btn.active {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

.tracker-progress {
  margin-top: 16px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.tracker-progress strong {
  color: var(--accent);
}

/* ============================================
   FACTS / STATS GRID
   ============================================ */
.stat-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: all var(--transition);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px var(--shadow-md);
}

.stat-icon {
  font-size: 2.5rem;
  margin-bottom: 12px;
  display: block;
}

.stat-value {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1.1;
  margin-bottom: 4px;
}

.stat-label {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
}

/* ============================================
   BLOG / ARTICLE CARDS
   ============================================ */
.blog-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
}

.blog-card:hover {
  box-shadow: 0 8px 30px var(--shadow-md);
  transform: translateY(-4px);
  border-color: var(--accent);
}

.blog-card-header {
  padding: 24px 24px 0;
}

.blog-card-body {
  padding: 16px 24px 24px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.blog-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 8px;
  line-height: 1.4;
}

.blog-card-excerpt {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
  flex: 1;
}

.blog-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  border-top: 1px solid var(--border-light);
  font-size: 0.85rem;
  color: var(--text-light);
}

.blog-card-link {
  color: var(--accent);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 4px;
  transition: gap var(--transition);
}

.blog-card:hover .blog-card-link {
  gap: 8px;
}

/* ============================================
   ARTICLE CONTENT
   ============================================ */
.article-content h2 {
  margin-top: 32px;
  margin-bottom: 12px;
  font-size: 1.4rem;
  color: var(--text);
}

.article-content h3 {
  margin-top: 24px;
  margin-bottom: 8px;
  font-size: 1.15rem;
  color: var(--text);
}

.article-content p {
  margin-bottom: 16px;
  line-height: 1.8;
  color: var(--text);
}

.article-content ul,
.article-content ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.article-content li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 0.95rem;
}

.article-content th,
.article-content td {
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.article-content th {
  background: var(--bg-secondary);
  font-weight: 600;
}

.article-content a {
  color: var(--accent);
  text-decoration: underline;
}

/* ============================================
   CTA SECTION
   ============================================ */
.cta-section {
  background: var(--gradient-primary);
  color: white;
  padding: 80px 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -25%;
  width: 50%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
}

.cta-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.cta-text {
  font-size: 1.15rem;
  opacity: 0.9;
  margin-bottom: 32px;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

/* ============================================
   CALCULATOR
   ============================================ */
.calculator {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: 0 4px 20px var(--shadow-md);
  margin-bottom: 32px;
}

.form-group {
  margin-bottom: 28px;
}

.form-label {
  display: block;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text);
  font-size: 0.95rem;
}

.form-input {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font-size: 1rem;
  transition: all var(--transition);
  font-family: var(--font-sans);
}

.form-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px var(--shadow-accent);
}

.slider-container {
  display: flex;
  align-items: center;
  gap: 16px;
}

.slider {
  flex: 1;
  height: 8px;
  border-radius: 4px;
  background: var(--bg-secondary);
  outline: none;
  -webkit-appearance: none;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  transition: all var(--transition);
  box-shadow: 0 2px 8px var(--shadow-accent);
}

.slider::-webkit-slider-thumb:hover {
  transform: scale(1.2);
  box-shadow: 0 4px 12px var(--shadow-accent);
}

.slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
  box-shadow: 0 2px 8px var(--shadow-accent);
}

.slider-value {
  min-width: 60px;
  text-align: center;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--accent);
}

/* Segmented Control */
.segmented-control {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.segment-btn {
  flex: 1;
  min-width: 120px;
  padding: 12px 16px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  text-align: center;
  font-family: var(--font-sans);
  font-size: 0.9rem;
}

.segment-btn:hover {
  border-color: var(--accent);
  background: var(--accent-light);
}

.segment-btn.active {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  box-shadow: 0 4px 12px var(--shadow-accent);
}

/* Toggle Switch */
.toggle-group {
  display: flex;
  gap: 14px;
  align-items: center;
  justify-content: center;
}

.toggle-switch {
  position: relative;
  width: 60px;
  height: 32px;
  background: var(--border);
  border-radius: 16px;
  cursor: pointer;
  transition: background var(--transition);
}

.toggle-switch.active {
  background: var(--accent);
}

.toggle-slider {
  position: absolute;
  top: 4px;
  left: 4px;
  width: 24px;
  height: 24px;
  background: white;
  border-radius: 50%;
  transition: transform var(--transition);
  box-shadow: 0 2px 4px rgba(0,0,0,0.15);
}

.toggle-switch.active .toggle-slider {
  transform: translateX(28px);
}

.toggle-label {
  font-weight: 700;
  min-width: 40px;
  transition: color var(--transition);
}

.toggle-label.active {
  color: var(--accent);
}

/* Stepper */
.stepper {
  display: flex;
  align-items: center;
  gap: 16px;
}

.stepper-btn {
  width: 40px;
  height: 40px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font-size: 1.3rem;
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-sans);
}

.stepper-btn:hover {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  transform: scale(1.05);
}

.stepper-value {
  min-width: 40px;
  text-align: center;
  font-weight: 700;
  font-size: 1.2rem;
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  padding: 12px 28px;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  text-decoration: none;
  font-family: var(--font-sans);
  letter-spacing: -0.01em;
}

.btn-primary {
  background: var(--accent);
  color: white;
  box-shadow: 0 4px 15px var(--shadow-accent);
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px var(--shadow-accent);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text);
  border: 2px solid var(--border);
}

.btn-secondary:hover {
  background: var(--bg-tertiary);
  border-color: var(--accent);
}

.btn-white {
  background: white;
  color: var(--accent);
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.btn-white:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.btn-outline {
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
}

.btn-outline:hover {
  background: var(--accent);
  color: white;
}

.btn-block {
  width: 100%;
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.1rem;
  border-radius: var(--radius);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.85rem;
}

/* Preset Chips */
.preset-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 28px;
}

.chip {
  padding: 8px 18px;
  border: 2px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--bg);
  color: var(--text);
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--transition);
  font-weight: 500;
}

.chip:hover {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px var(--shadow-accent);
}

/* ============================================
   RESULTS
   ============================================ */
.results {
  margin-top: 32px;
  padding-top: 32px;
  border-top: 2px solid var(--border);
}

.result-main {
  text-align: center;
  padding: 40px;
  background: var(--gradient-primary);
  color: white;
  border-radius: var(--radius);
  margin-bottom: 24px;
  position: relative;
  overflow: hidden;
}

.result-main::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -25%;
  width: 50%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
}

.result-value {
  font-size: 4.5rem;
  font-weight: 800;
  margin-bottom: 8px;
  position: relative;
  line-height: 1;
}

.result-label {
  font-size: 1.2rem;
  opacity: 0.9;
  font-weight: 500;
  position: relative;
}

.result-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.result-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 24px;
  text-align: center;
  transition: all var(--transition);
}

.result-card:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 12px var(--shadow);
}

.result-card-value {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 4px;
  line-height: 1;
}

.result-card-label {
  color: var(--text-muted);
  font-size: 0.85rem;
  font-weight: 500;
}

/* Schedule Timeline */
.schedule {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 24px;
}

.schedule-title {
  font-weight: 700;
  margin-bottom: 20px;
  font-size: 1.1rem;
}

.timeline {
  display: flex;
  justify-content: space-between;
  gap: 16px;
}

.timeline-item {
  flex: 1;
  text-align: center;
  padding: 16px;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.timeline-item:hover {
  background: var(--accent-light);
}

.timeline-icon {
  font-size: 2rem;
  margin-bottom: 8px;
}

.timeline-time {
  font-weight: 700;
  margin-bottom: 4px;
  font-size: 0.95rem;
}

.timeline-amount {
  color: var(--accent);
  font-weight: 700;
  font-size: 1.1rem;
}

/* ============================================
   ACCORDION
   ============================================ */
.accordion {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.accordion-item {
  border-bottom: 1px solid var(--border);
}

.accordion-item:last-child {
  border-bottom: none;
}

.accordion-header {
  padding: 18px 24px;
  background: var(--bg-secondary);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 700;
  transition: background var(--transition);
  font-size: 0.95rem;
}

.accordion-header:hover {
  background: var(--bg-tertiary);
}

.accordion-icon {
  transition: transform var(--transition);
  font-size: 0.8rem;
}

.accordion-item.active .accordion-icon {
  transform: rotate(180deg);
}

.accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.accordion-item.active .accordion-content {
  max-height: 500px;
}

.accordion-body {
  padding: 24px;
  line-height: 1.8;
}

/* ============================================
   ALERT
   ============================================ */
.alert {
  padding: 16px 24px;
  border-radius: var(--radius-sm);
  margin-bottom: 24px;
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 0.95rem;
}

.alert-warning {
  background: #fef3c7;
  border: 1px solid #fcd34d;
  color: #92400e;
}

.alert-info {
  background: #dbeafe;
  border: 1px solid #93c5fd;
  color: #1e40af;
}

.alert-success {
  background: #d1fae5;
  border: 1px solid #6ee7b7;
  color: #065f46;
}

[data-theme="dark"] .alert-warning {
  background: #78350f;
  color: #fef3c7;
  border-color: #92400e;
}

[data-theme="dark"] .alert-info {
  background: #1e3a5f;
  color: #dbeafe;
  border-color: #1e40af;
}

[data-theme="dark"] .alert-success {
  background: #064e3b;
  color: #d1fae5;
  border-color: #065f46;
}

/* Disclaimer */
.disclaimer {
  background: var(--bg-secondary);
  border-left: 4px solid var(--accent);
  padding: 20px 24px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 32px 0;
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ============================================
   ARTICLE CONTENT
   ============================================ */
.article-content {
  max-width: 800px;
  margin: 0 auto;
}

.article-header {
  margin-bottom: 40px;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  margin-top: 16px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.article-meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.article-content h2 {
  font-size: 1.8rem;
  margin-top: 48px;
  margin-bottom: 16px;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text);
}

.article-content h3 {
  font-size: 1.35rem;
  margin-top: 36px;
  margin-bottom: 12px;
  font-weight: 700;
}

.article-content p {
  margin-bottom: 20px;
  line-height: 1.9;
  color: var(--text);
}

.article-content ul,
.article-content ol {
  margin-bottom: 20px;
  padding-left: 24px;
}

.article-content li {
  margin-bottom: 10px;
  line-height: 1.8;
}

.article-content strong {
  font-weight: 700;
  color: var(--accent);
}

.article-content blockquote {
  border-left: 4px solid var(--accent);
  padding: 16px 24px;
  margin: 24px 0;
  background: var(--accent-light);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  color: var(--text-muted);
}

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 0.95rem;
}

.article-content table th,
.article-content table td {
  padding: 12px 16px;
  border: 1px solid var(--border);
  text-align: left;
}

.article-content table th {
  background: var(--bg-secondary);
  font-weight: 700;
}

.article-content table tr:hover {
  background: var(--bg-secondary);
}

/* Table of Contents */
.toc {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 32px;
}

.toc-title {
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.toc-list li {
  margin-bottom: 6px;
}

.toc-list a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  padding: 4px 0;
  display: block;
  transition: color var(--transition);
}

.toc-list a:hover {
  color: var(--accent);
}

/* ============================================
   BREADCRUMB
   ============================================ */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
  font-size: 0.9rem;
}

.breadcrumb-item {
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition);
}

.breadcrumb-item:hover {
  color: var(--accent);
}

.breadcrumb-separator {
  color: var(--text-light);
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 60px 24px 24px;
  margin-top: 0;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-top: 12px;
}

.footer-section h3 {
  font-size: 1rem;
  margin-bottom: 16px;
  font-weight: 700;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition);
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: var(--accent);
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.85rem;
}

@media (max-width: 768px) {
  .footer-content {
    grid-template-columns: 1fr 1fr;
    gap: 24px;
  }
}

@media (max-width: 480px) {
  .footer-content {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   SEARCH
   ============================================ */
.search-box {
  position: relative;
  margin-bottom: 32px;
}

.search-input {
  width: 100%;
  padding: 16px 52px 16px 24px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  color: var(--text);
  font-size: 1.1rem;
  transition: all var(--transition);
  font-family: var(--font-sans);
}

.search-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px var(--shadow-accent);
}

.search-icon {
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 1.3rem;
}

.search-results {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.search-result {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 24px;
  text-decoration: none;
  color: var(--text);
  transition: all var(--transition);
}

.search-result:hover {
  box-shadow: 0 4px 16px var(--shadow-md);
  transform: translateY(-2px);
  border-color: var(--accent);
}

.search-result-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--accent);
}

.search-result-excerpt {
  color: var(--text-muted);
  line-height: 1.7;
  font-size: 0.95rem;
}

/* ============================================
   FAQ
   ============================================ */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}

.faq-item:hover {
  border-color: var(--accent);
}

.faq-question {
  padding: 20px 24px;
  background: var(--bg);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 700;
  font-size: 1.05rem;
  transition: background var(--transition);
  width:100%;
}

.faq-question:hover {
  background: var(--bg-secondary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.faq-item.active .faq-answer {
  max-height: 800px;
}

.faq-answer-content {
  padding: 20px 24px;
  line-height: 1.9;
  color: var(--text-muted);
}

/* ============================================
   ADSENSE
   ============================================ */
.ad-container {
  margin: 32px 0;
  text-align: center;
  padding: 16px 0;
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
  min-height: 100px;
  overflow: hidden;
}

.ad-container-inline {
  margin: 24px 0;
  text-align: center;
  min-height: 90px;
  overflow: hidden;
}

.ad-label {
  font-size: 0.65rem;
  color: var(--text-light);
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  font-weight: 500;
}

.ad-container-sidebar {
  position: sticky;
  top: 80px;
  text-align: center;
  min-height: 250px;
  padding: 12px 0;
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
  .hero {
    padding: 60px 20px 80px;
  }

  .hero h1 {
    font-size: 2.2rem;
  }
  
  .hero p {
    font-size: 1.05rem;
  }

  .hero-stats {
    gap: 24px;
    flex-wrap: wrap;
  }

  .hero-stat-value {
    font-size: 1.8rem;
  }
  
  .section {
    padding: 48px 16px;
  }

  .section-title {
    font-size: 1.7rem;
  }

  .section-subtitle {
    font-size: 1rem;
    margin-bottom: 32px;
  }
  
  .result-value {
    font-size: 3.5rem;
  }
  
  .timeline {
    flex-direction: column;
    gap: 12px;
  }
  
  .segment-btn {
    min-width: 100px;
    font-size: 0.85rem;
    padding: 10px 12px;
  }
  
  .calculator {
    padding: 20px;
  }

  .card {
    padding: 20px;
  }

  .cta-title {
    font-size: 1.7rem;
  }

  .steps {
    gap: 24px;
  }

  .tracker-visual {
    width: 160px;
    height: 160px;
  }

  .tracker-value {
    font-size: 2rem;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.8rem;
  }

  .hero-stats {
    flex-direction: column;
    gap: 16px;
  }

  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

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

.text-accent {
  color: var(--accent);
}

.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 32px; }
.mt-5 { margin-top: 48px; }

.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mb-4 { margin-bottom: 32px; }
.mb-5 { margin-bottom: 48px; }

.py-1 { padding-top: 8px; padding-bottom: 8px; }
.py-2 { padding-top: 16px; padding-bottom: 16px; }
.py-3 { padding-top: 24px; padding-bottom: 24px; }
.py-4 { padding-top: 32px; padding-bottom: 32px; }

.hidden {
  display: none !important;
}

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

/* ============================================
   ANIMATIONS
   ============================================ */
.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.fade-in {
  animation: fadeIn 0.4s ease-out;
}

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

.slide-up {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-up.visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.animate-float {
  animation: float 3s ease-in-out infinite;
}

/* Counter Animation */
.counter {
  display: inline-block;
}

/* ============================================
   RELATED ARTICLES SECTION
   ============================================ */
.related-articles {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.related-articles h2 {
  font-size: 1.5rem;
  margin-bottom: 20px;
}

/* ============================================
   TAG CLOUD
   ============================================ */
.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  display: inline-block;
  padding: 6px 14px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: all var(--transition);
  text-decoration: none;
}

.tag:hover {
  background: var(--accent-light);
  color: var(--accent);
  border-color: var(--accent);
}

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
  .header, .footer, .ad-container, .cta-section {
    display: none !important;
  }
  
  body {
    color: black;
    background: white;
  }
  
  .article-content {
    max-width: 100%;
  }
}