:root {
  --primary: #0071e3;
  --primary-hover: #0077ed;
  --android-color: #10b981;
  --android-hover: #059669;
  --dark-bg: #090d16;
  --dark-surface: #111827;
  --dark-card: #1f2937;
  --light-bg: #f8fafc;
  --light-surface: #ffffff;
  --light-border: #e2e8f0;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-light: #f8fafc;
  --accent-amber: #f59e0b;
  --accent-red: #ef4444;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--light-bg);
  color: var(--text-main);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--primary-hover);
}

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

.container {
  width: 100%;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* TOP BAR */
.top-notice-bar {
  background-color: #0f172a;
  color: #94a3b8;
  font-size: 13px;
  padding: 8px 0;
  border-bottom: 1px solid #1e293b;
}

.top-notice-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.top-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
  padding: 2px 8px;
  border-radius: 9999px;
  font-weight: 500;
  font-size: 12px;
}

/* HEADER & NAV */
.site-header {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--light-border);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: box-shadow 0.3s ease;
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-main);
  font-weight: 800;
  font-size: 22px;
  letter-spacing: -0.5px;
}

.brand-logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, #0071e3 0%, #10b981 100%);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  box-shadow: 0 4px 10px rgba(0, 113, 227, 0.3);
}

.brand-logo-text span {
  color: var(--primary);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 20px;
  align-items: center;
}

.nav-item a {
  color: #475569;
  font-weight: 500;
  font-size: 15px;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}

.nav-item a:hover,
.nav-item.active a {
  color: var(--primary);
  background-color: rgba(0, 113, 227, 0.08);
}

.nav-cta-btn {
  background: var(--primary);
  color: #ffffff !important;
  font-weight: 600;
  font-size: 14px;
  padding: 10px 18px;
  border-radius: 9999px;
  box-shadow: 0 2px 8px rgba(0, 113, 227, 0.25);
  transition: all 0.2s ease;
}

.nav-cta-btn:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-main);
}

/* HERO SECTION SPLIT INTO TWO BLOCKS */
.hero-split-section {
  background: linear-gradient(180deg, #0f172a 0%, #1e293b 100%);
  color: #ffffff;
  padding: 60px 0 80px 0;
  position: relative;
  overflow: hidden;
}

.hero-intro {
  text-align: center;
  max-width: 800px;
  margin: 0 auto 50px auto;
}

.hero-tag {
  display: inline-block;
  background: rgba(255, 255, 255, 0.1);
  color: #38bdf8;
  border: 1px solid rgba(56, 189, 248, 0.3);
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  padding: 4px 14px;
  border-radius: 9999px;
  margin-bottom: 16px;
}

.hero-intro h1 {
  font-size: clamp(30px, 4.5vw, 48px);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.8px;
}

.hero-intro p {
  color: #cbd5e1;
  font-size: 18px;
  line-height: 1.6;
}

/* TWO BLOCKS GRID */
.split-blocks-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 30px;
  align-items: stretch;
}

.device-block-card {
  background: rgba(30, 41, 59, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  overflow: hidden;
  backdrop-filter: blur(16px);
  display: flex;
  flex-direction: column;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.device-block-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 30px -10px rgba(0, 0, 0, 0.5);
}

.card-iphone {
  border-top: 4px solid var(--primary);
}

.card-iphone:hover {
  border-color: rgba(0, 113, 227, 0.5);
}

.card-android {
  border-top: 4px solid var(--android-color);
}

.card-android:hover {
  border-color: rgba(16, 185, 129, 0.5);
}

.device-card-header {
  padding: 30px 30px 20px 30px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 15px;
}

.device-title-wrap h2 {
  font-size: 26px;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}

.card-iphone .device-title-wrap h2 {
  color: #60a5fa;
}

.card-android .device-title-wrap h2 {
  color: #34d399;
}

.device-subtitle {
  color: #94a3b8;
  font-size: 14px;
}

.device-badge-os {
  background: rgba(255, 255, 255, 0.1);
  font-size: 12px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  white-space: nowrap;
}

.device-card-image {
  position: relative;
  height: 220px;
  overflow: hidden;
}

.device-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.device-block-card:hover .device-card-image img {
  transform: scale(1.04);
}

.image-overlay-badge {
  position: absolute;
  bottom: 12px;
  left: 16px;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(8px);
  color: #f8fafc;
  padding: 6px 14px;
  border-radius: 9999px;
  font-size: 12px;
  font-weight: 600;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.device-card-body {
  padding: 30px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  flex: 1;
}

.rule-box {
  background: rgba(15, 23, 42, 0.5);
  border-radius: var(--radius-md);
  padding: 18px;
  border-left: 3px solid rgba(255, 255, 255, 0.2);
}

.card-iphone .rule-box {
  border-left-color: var(--primary);
}

.card-android .rule-box {
  border-left-color: var(--android-color);
}

.rule-box-title {
  font-size: 15px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.card-iphone .rule-box-title {
  color: #93c5fd;
}

.card-android .rule-box-title {
  color: #6ee7b7;
}

.rule-box-text {
  font-size: 14.5px;
  color: #cbd5e1;
  line-height: 1.55;
}

.rule-stat-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-top: 10px;
}

.stat-chip {
  background: rgba(255, 255, 255, 0.05);
  padding: 10px 12px;
  border-radius: var(--radius-sm);
}

.stat-label {
  font-size: 11px;
  text-transform: uppercase;
  color: #94a3b8;
  font-weight: 600;
}

.stat-value {
  font-size: 15px;
  font-weight: 700;
  color: #ffffff;
}

.mistake-list, .tips-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.mistake-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 14px;
  color: #cbd5e1;
}

.mistake-item .icon-warn {
  color: #f87171;
  flex-shrink: 0;
  font-weight: bold;
}

.tips-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 14px;
  color: #cbd5e1;
}

.tips-item .icon-check {
  color: #34d399;
  flex-shrink: 0;
  font-weight: bold;
}

.device-card-footer {
  padding: 20px 30px;
  background: rgba(15, 23, 42, 0.4);
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.manufacturer-tag {
  font-size: 12px;
  color: #94a3b8;
}

/* SECTION TITLES & LAYOUT */
.section {
  padding: 80px 0;
}

.section-alt {
  background-color: #ffffff;
}

.section-header {
  text-align: center;
  max-width: 750px;
  margin: 0 auto 50px auto;
}

.section-subtitle {
  color: var(--primary);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 8px;
}

.section-title {
  font-size: clamp(26px, 3.5vw, 36px);
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.5px;
  margin-bottom: 14px;
}

.section-desc {
  font-size: 17px;
  color: var(--text-muted);
}

/* COMPARISON TABLE */
.table-responsive {
  overflow-x: auto;
  background: #ffffff;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--light-border);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 15px;
}

.comparison-table th {
  background: #f1f5f9;
  padding: 16px 20px;
  font-weight: 700;
  color: #1e293b;
  border-bottom: 2px solid var(--light-border);
}

.comparison-table td {
  padding: 16px 20px;
  border-bottom: 1px solid var(--light-border);
  vertical-align: top;
}

.comparison-table tr:hover td {
  background-color: #f8fafc;
}

.comparison-table .feature-title {
  font-weight: 600;
  color: #0f172a;
}

/* INTERACTIVE CALCULATOR */
.calc-card {
  background: #ffffff;
  border: 1px solid var(--light-border);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-lg);
  max-width: 900px;
  margin: 0 auto;
}

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
}

.calc-form-group {
  margin-bottom: 22px;
}

.calc-label {
  display: block;
  font-weight: 600;
  font-size: 14px;
  margin-bottom: 8px;
  color: #334155;
}

.calc-select, .calc-range {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-family: inherit;
}

.range-display {
  display: flex;
  justify-content: space-between;
  margin-top: 6px;
  font-size: 13px;
  color: var(--text-muted);
}

.range-display span.active-val {
  font-weight: 700;
  color: var(--primary);
}

.calc-result-panel {
  background: #0f172a;
  color: #ffffff;
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.calc-result-title {
  font-size: 13px;
  text-transform: uppercase;
  color: #94a3b8;
  letter-spacing: 1px;
  margin-bottom: 12px;
}

.calc-result-time {
  font-size: 38px;
  font-weight: 800;
  color: #38bdf8;
  line-height: 1;
  margin-bottom: 12px;
}

.calc-health-bar-bg {
  background: rgba(255, 255, 255, 0.1);
  height: 8px;
  border-radius: 9999px;
  overflow: hidden;
  margin-bottom: 12px;
}

.calc-health-bar-fill {
  background: #10b981;
  height: 100%;
  width: 95%;
  transition: width 0.4s ease, background-color 0.4s ease;
}

.calc-recommendation {
  font-size: 14px;
  color: #cbd5e1;
  line-height: 1.5;
}

/* EDITORIAL ARTICLES & GUIDES GRID */
.guides-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.guide-card {
  background: #ffffff;
  border: 1px solid var(--light-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
}

.guide-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.guide-card-img {
  height: 190px;
  overflow: hidden;
}

.guide-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s;
}

.guide-card:hover .guide-card-img img {
  transform: scale(1.05);
}

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

.guide-category {
  font-size: 12px;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.guide-title {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 10px;
  color: #0f172a;
}

.guide-excerpt {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 18px;
  flex: 1;
}

.guide-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: #94a3b8;
  border-top: 1px solid #f1f5f9;
  padding-top: 14px;
}

/* FAQ ACCORDION */
.faq-wrap {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: #ffffff;
  border: 1px solid var(--light-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s;
}

.faq-item.active {
  border-color: var(--primary);
}

.faq-trigger {
  width: 100%;
  padding: 20px 24px;
  text-align: left;
  background: none;
  border: none;
  font-size: 16px;
  font-weight: 700;
  color: #0f172a;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-family: inherit;
}

.faq-trigger .icon-toggle {
  width: 20px;
  height: 20px;
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.faq-item.active .faq-trigger .icon-toggle {
  transform: rotate(180deg);
}

.faq-content {
  display: none;
  padding: 0 24px 22px 24px;
  font-size: 15px;
  color: #475569;
  line-height: 1.65;
}

.faq-item.active .faq-content {
  display: block;
}

/* DISCLAIMER / NOTICE CALLOUT */
.editorial-disclaimer-box {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-left: 4px solid #3b82f6;
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  margin: 40px auto 0 auto;
  max-width: 900px;
  font-size: 13.5px;
  color: #475569;
  line-height: 1.6;
}

.editorial-disclaimer-box strong {
  color: #1e293b;
}

/* FOOTER */
.site-footer {
  background-color: #0b1120;
  color: #94a3b8;
  padding: 70px 0 30px 0;
  font-size: 14px;
  border-top: 1px solid #1e293b;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 50px;
}

.footer-col h3 {
  color: #f8fafc;
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 20px;
  letter-spacing: -0.3px;
}

.footer-about p {
  color: #94a3b8;
  line-height: 1.6;
  margin-bottom: 16px;
  font-size: 14px;
}

.footer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-nav a {
  color: #94a3b8;
  font-size: 14px;
  transition: color 0.2s;
}

.footer-nav a:hover {
  color: #ffffff;
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 12px;
  color: #cbd5e1;
}

.footer-contact-item a {
  color: #cbd5e1;
}

.footer-contact-item a:hover {
  color: var(--primary);
}

.footer-badges {
  display: flex;
  gap: 10px;
  margin-top: 16px;
  flex-wrap: wrap;
}

.f-badge {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: 12px;
  color: #cbd5e1;
}

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
}

.footer-bottom-links {
  display: flex;
  gap: 20px;
  list-style: none;
  flex-wrap: wrap;
}

.footer-bottom-links a {
  color: #64748b;
}

.footer-bottom-links a:hover {
  color: #cbd5e1;
}

/* INNER PAGES / SUBPAGES STYLING */
.page-hero {
  background: linear-gradient(180deg, #0f172a 0%, #1e293b 100%);
  color: #ffffff;
  padding: 50px 0 60px 0;
  text-align: center;
}

.page-hero h1 {
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 800;
  margin-bottom: 12px;
}

.page-hero p {
  color: #cbd5e1;
  font-size: 17px;
  max-width: 650px;
  margin: 0 auto;
}

.content-wrapper {
  background: #ffffff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--light-border);
  padding: 40px;
  margin: -30px auto 60px auto;
  max-width: 950px;
  position: relative;
  z-index: 10;
}

.content-block {
  margin-bottom: 36px;
}

.content-block h2 {
  font-size: 22px;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--light-border);
}

.content-block h3 {
  font-size: 17px;
  font-weight: 600;
  color: #1e293b;
  margin: 18px 0 8px 0;
}

.content-block p {
  margin-bottom: 14px;
  color: #475569;
  line-height: 1.7;
}

.content-block ul {
  padding-left: 20px;
  margin-bottom: 16px;
  color: #475569;
}

.content-block li {
  margin-bottom: 8px;
}

/* CONTACT FORM & MAP */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
}

.contact-card-info {
  background: #f8fafc;
  border: 1px solid var(--light-border);
  border-radius: var(--radius-md);
  padding: 28px;
}

.contact-info-row {
  margin-bottom: 18px;
}

.contact-info-label {
  font-size: 12px;
  text-transform: uppercase;
  color: #64748b;
  font-weight: 700;
  margin-bottom: 4px;
}

.contact-info-val {
  font-size: 15px;
  color: #0f172a;
  font-weight: 500;
}

.form-group {
  margin-bottom: 18px;
}

.form-label {
  display: block;
  font-weight: 600;
  font-size: 14px;
  margin-bottom: 6px;
  color: #334155;
}

.form-input, .form-textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-family: inherit;
  transition: border-color 0.2s;
}

.form-input:focus, .form-textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.15);
}

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

.btn-submit {
  background: var(--primary);
  color: #ffffff;
  border: none;
  padding: 14px 24px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  width: 100%;
  transition: background-color 0.2s;
}

.btn-submit:hover {
  background: var(--primary-hover);
}

.map-wrapper {
  margin-top: 30px;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--light-border);
}

.map-wrapper iframe {
  width: 100%;
  height: 300px;
  border: 0;
  display: block;
}

.form-response-msg {
  padding: 14px;
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  display: none;
  font-size: 14px;
}

.form-response-msg.success {
  background: #ecfdf5;
  color: #065f46;
  border: 1px solid #a7f3d0;
  display: block;
}

.form-response-msg.error {
  background: #fef2f2;
  color: #991b1b;
  border: 1px solid #fecaca;
  display: block;
}

/* RESPONSIVE BREAKPOINTS */
@media (max-width: 992px) {
  .split-blocks-grid {
    grid-template-columns: 1fr;
  }
  .guides-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .calc-grid, .contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .guides-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .main-nav {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: #ffffff;
    border-bottom: 1px solid var(--light-border);
    padding: 20px;
    flex-direction: column;
    box-shadow: var(--shadow-lg);
  }
  .main-nav.open {
    display: flex;
  }
  .nav-links {
    flex-direction: column;
    width: 100%;
  }
  .nav-item {
    width: 100%;
  }
  .nav-item a {
    display: block;
    padding: 10px 14px;
  }
  .mobile-menu-toggle {
    display: block;
  }
  .content-wrapper {
    padding: 24px;
    margin-top: -20px;
  }
}