/* ============================================================
   5G Bahrain - Main Stylesheet
   Minimal Tech Grid | Mobile-First
   ============================================================ */

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

:root {
  --white: #ffffff;
  --black: #0a0a0a;
  --blue-accent: #0099cc;
  --blue-light: #e6f6fb;
  --blue-mid: #00b4e6;
  --blue-dark: #006d99;
  --grey-100: #f5f7f9;
  --grey-200: #e8ecf0;
  --grey-400: #9aa5b4;
  --grey-600: #4a5568;
  --grey-800: #1a202c;
  --font-sans: 'Inter', 'Segoe UI', Arial, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
  --max-width: 1140px;
  --nav-height: 64px;
  --radius: 4px;
  --radius-lg: 8px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.10);
  --transition: 0.2s ease;
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--white);
  color: var(--black);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

img, svg { display: block; max-width: 100%; }
a { color: var(--blue-accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--blue-dark); }
ul { list-style: none; }

/* --- Typography --- */
h1, h2, h3, h4, h5 {
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--black);
}
h1 { font-size: clamp(2rem, 5vw, 3.2rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.2rem); }
h3 { font-size: clamp(1.1rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.1rem; }
p { margin-bottom: 1rem; color: var(--grey-600); }
p:last-child { margin-bottom: 0; }

/* --- Layout Utilities --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.section {
  padding: 5rem 0;
}

.section--alt {
  background-color: var(--grey-100);
}

.section--blue {
  background-color: var(--blue-light);
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

@media (min-width: 640px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 900px) {
  .grid-2 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-4 { grid-template-columns: repeat(4, 1fr); }
}

.text-center { text-align: center; }
.text-mono { font-family: var(--font-mono); }

/* --- Navigation --- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.97);
  border-bottom: 1px solid var(--grey-200);
  backdrop-filter: blur(8px);
  height: var(--nav-height);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--black);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.nav__logo-icon {
  width: 32px;
  height: 32px;
  background: var(--blue-accent);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav__logo-icon svg { width: 18px; height: 18px; }

.nav__links {
  display: none;
  gap: 0.25rem;
  align-items: center;
}

.nav__links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--grey-600);
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius);
  transition: all var(--transition);
}

.nav__links a:hover,
.nav__links a.active {
  color: var(--blue-accent);
  background: var(--blue-light);
}

.nav__hamburger {
  display: flex;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 0.5rem;
  background: none;
  border: none;
}

.nav__hamburger span {
  width: 22px;
  height: 2px;
  background: var(--black);
  border-radius: 2px;
  transition: all var(--transition);
  display: block;
}

.nav__mobile {
  display: none;
  flex-direction: column;
  background: var(--white);
  border-bottom: 1px solid var(--grey-200);
  padding: 1rem 1.25rem;
  gap: 0.25rem;
}

.nav__mobile.open { display: flex; }

.nav__mobile a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--grey-600);
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius);
  transition: all var(--transition);
}

.nav__mobile a:hover,
.nav__mobile a.active {
  color: var(--blue-accent);
  background: var(--blue-light);
}

@media (min-width: 900px) {
  .nav__links { display: flex; }
  .nav__hamburger { display: none; }
}

/* --- Hero --- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 5rem 0 4rem;
  background: var(--white);
}

.hero__grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0,153,204,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,153,204,0.06) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--blue-accent);
  background: var(--blue-light);
  border: 1px solid rgba(0,153,204,0.2);
  padding: 0.35rem 0.85rem;
  border-radius: 100px;
  margin-bottom: 1.5rem;
}

.hero__eyebrow::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--blue-accent);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.4); }
}

.hero h1 {
  margin-bottom: 1.25rem;
}

.hero h1 span {
  color: var(--blue-accent);
}

.hero__lead {
  font-size: clamp(1rem, 2vw, 1.175rem);
  color: var(--grey-600);
  margin-bottom: 2rem;
  max-width: 600px;
}

.hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-top: 2.5rem;
  padding-top: 2.5rem;
  border-top: 1px solid var(--grey-200);
}

.hero__stat-item {
  display: flex;
  flex-direction: column;
}

.hero__stat-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--black);
  letter-spacing: -0.03em;
}

.hero__stat-value span {
  color: var(--blue-accent);
}

.hero__stat-label {
  font-size: 0.8rem;
  color: var(--grey-400);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 500;
}

/* --- Section Headers --- */
.section-header {
  margin-bottom: 3rem;
}

.section-header--center {
  text-align: center;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}

.section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue-accent);
  margin-bottom: 0.75rem;
}

.section-header h2 {
  margin-bottom: 0.75rem;
}

.section-header p {
  font-size: 1.05rem;
}

/* --- Cards --- */
.card {
  background: var(--white);
  border: 1px solid var(--grey-200);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: box-shadow var(--transition), border-color var(--transition);
}

.card:hover {
  box-shadow: var(--shadow-md);
  border-color: rgba(0,153,204,0.25);
}

.card__icon {
  width: 44px;
  height: 44px;
  background: var(--blue-light);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
}

.card__icon svg {
  width: 22px;
  height: 22px;
  color: var(--blue-accent);
}

.card h3 {
  font-size: 1.05rem;
  margin-bottom: 0.6rem;
}

.card p {
  font-size: 0.9rem;
  line-height: 1.65;
}

/* --- Info Blocks --- */
.info-block {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
  padding: 1.5rem;
  background: var(--white);
  border: 1px solid var(--grey-200);
  border-radius: var(--radius-lg);
  border-left: 3px solid var(--blue-accent);
}

.info-block__icon {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  background: var(--blue-light);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
}

.info-block__icon svg {
  width: 20px;
  height: 20px;
  color: var(--blue-accent);
}

.info-block__text h4 {
  margin-bottom: 0.4rem;
}

.info-block__text p {
  font-size: 0.9rem;
  margin: 0;
}

/* --- Tech Spec Table --- */
.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.spec-table th {
  background: var(--grey-100);
  padding: 0.75rem 1rem;
  text-align: left;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--grey-600);
  border-bottom: 2px solid var(--grey-200);
}

.spec-table td {
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--grey-200);
  color: var(--grey-800);
  vertical-align: top;
}

.spec-table tr:last-child td { border-bottom: none; }

.spec-table tr:hover td { background: var(--grey-100); }

.spec-table td:first-child {
  font-weight: 600;
  color: var(--black);
  white-space: nowrap;
}

.spec-badge {
  display: inline-block;
  background: var(--blue-light);
  color: var(--blue-dark);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
}

/* --- FAQ --- */
.faq-item {
  border-bottom: 1px solid var(--grey-200);
}

.faq-item:first-child {
  border-top: 1px solid var(--grey-200);
}

.faq-question {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 1.25rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 600;
  color: var(--black);
  transition: color var(--transition);
}

.faq-question:hover { color: var(--blue-accent); }

.faq-question__icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  background: var(--grey-100);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition), transform var(--transition);
}

.faq-question__icon svg {
  width: 12px;
  height: 12px;
  color: var(--grey-600);
  transition: transform var(--transition);
}

.faq-item.open .faq-question__icon {
  background: var(--blue-accent);
  transform: rotate(45deg);
}

.faq-item.open .faq-question__icon svg { color: white; }

.faq-answer {
  display: none;
  padding: 0 0 1.25rem;
  color: var(--grey-600);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.open .faq-answer { display: block; }

/* --- Disclaimer Banner --- */
.disclaimer {
  background: var(--blue-light);
  border: 1px solid rgba(0,153,204,0.2);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  margin: 2rem 0;
}

.disclaimer__icon {
  flex-shrink: 0;
  color: var(--blue-accent);
  margin-top: 2px;
}

.disclaimer__icon svg { width: 20px; height: 20px; }

.disclaimer__text {
  font-size: 0.875rem;
  color: var(--grey-600);
  line-height: 1.6;
}

.disclaimer__text strong { color: var(--black); }

/* --- Contact --- */
.contact-card {
  background: var(--white);
  border: 1px solid var(--grey-200);
  border-radius: var(--radius-lg);
  padding: 2rem;
}

.contact-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--grey-200);
}

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

.contact-item__icon {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  background: var(--blue-light);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
}

.contact-item__icon svg {
  width: 20px;
  height: 20px;
  color: var(--blue-accent);
}

.contact-item__label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 600;
  color: var(--grey-400);
  margin-bottom: 0.25rem;
}

.contact-item__value {
  font-weight: 500;
  color: var(--black);
  font-size: 0.95rem;
}

/* --- Page Header (inner pages) --- */
.page-header {
  background: var(--white);
  padding: 3.5rem 0 3rem;
  border-bottom: 1px solid var(--grey-200);
  position: relative;
  overflow: hidden;
}

.page-header__grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0,153,204,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,153,204,0.05) 1px, transparent 1px);
  background-size: 32px 32px;
  pointer-events: none;
}

.page-header__content { position: relative; z-index: 1; }

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8rem;
  color: var(--grey-400);
  margin-bottom: 1rem;
}

.breadcrumb a { color: var(--grey-400); }
.breadcrumb a:hover { color: var(--blue-accent); }
.breadcrumb span { color: var(--black); font-weight: 500; }

/* --- Signal Diagram --- */
.signal-visual {
  position: relative;
  padding: 2rem;
  background: var(--grey-100);
  border-radius: var(--radius-lg);
  text-align: center;
  overflow: hidden;
}

.signal-rings {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  position: relative;
  width: 180px;
  height: 180px;
  margin: 0 auto;
}

.signal-rings__dot {
  position: absolute;
  width: 20px;
  height: 20px;
  background: var(--blue-accent);
  border-radius: 50%;
  z-index: 2;
}

.signal-rings__ring {
  position: absolute;
  border-radius: 50%;
  border: 2px solid var(--blue-accent);
  animation: ring-expand 3s ease-in-out infinite;
}

.signal-rings__ring:nth-child(2) { width: 60px; height: 60px; animation-delay: 0s; opacity: 0.7; }
.signal-rings__ring:nth-child(3) { width: 100px; height: 100px; animation-delay: 0.6s; opacity: 0.5; }
.signal-rings__ring:nth-child(4) { width: 140px; height: 140px; animation-delay: 1.2s; opacity: 0.3; }
.signal-rings__ring:nth-child(5) { width: 175px; height: 175px; animation-delay: 1.8s; opacity: 0.15; }

@keyframes ring-expand {
  0% { transform: scale(0.8); opacity: 0.8; }
  50% { transform: scale(1); opacity: 0.4; }
  100% { transform: scale(0.8); opacity: 0.8; }
}

/* --- Footer --- */
.footer {
  background: var(--grey-800);
  color: var(--grey-400);
  margin-top: auto;
}

.footer__main {
  padding: 3.5rem 0 2.5rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
}

@media (min-width: 640px) {
  .footer__main { grid-template-columns: 2fr 1fr 1fr; }
}

.footer__brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 1rem;
  color: var(--white);
  margin-bottom: 1rem;
}

.footer__brand-icon {
  width: 28px;
  height: 28px;
  background: var(--blue-accent);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
}

.footer__description {
  font-size: 0.875rem;
  line-height: 1.65;
  color: var(--grey-400);
  margin-bottom: 0;
}

.footer__col-title {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 1rem;
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer__links a {
  font-size: 0.875rem;
  color: var(--grey-400);
  transition: color var(--transition);
}

.footer__links a:hover { color: var(--blue-accent); }

.footer__bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 1.5rem 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  font-size: 0.8rem;
}

@media (min-width: 640px) {
  .footer__bottom {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

.footer__disclaimer {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.35);
  line-height: 1.6;
  max-width: 700px;
  margin-top: 0.25rem;
}

/* --- Utility --- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.7rem;
  border-radius: 100px;
  border: 1px solid var(--grey-200);
  color: var(--grey-600);
  background: var(--white);
}

.tag--blue {
  background: var(--blue-light);
  color: var(--blue-dark);
  border-color: rgba(0,153,204,0.2);
}

.divider {
  border: none;
  border-top: 1px solid var(--grey-200);
  margin: 2.5rem 0;
}

.highlight-box {
  background: linear-gradient(135deg, var(--blue-light) 0%, #f0faff 100%);
  border: 1px solid rgba(0,153,204,0.2);
  border-radius: var(--radius-lg);
  padding: 2rem;
}

.highlight-box h3 { margin-bottom: 0.75rem; }

/* Number list with line connector */
.step-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.step-item {
  display: flex;
  gap: 1.25rem;
  position: relative;
  padding-bottom: 2rem;
}

.step-item:last-child { padding-bottom: 0; }

.step-item::before {
  content: '';
  position: absolute;
  left: 16px;
  top: 36px;
  width: 2px;
  height: calc(100% - 12px);
  background: var(--grey-200);
}

.step-item:last-child::before { display: none; }

.step-num {
  flex-shrink: 0;
  width: 34px;
  height: 34px;
  background: var(--blue-accent);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  z-index: 1;
}

.step-content h4 { margin-bottom: 0.4rem; }
.step-content p { font-size: 0.9rem; margin: 0; }

/* Band comparison blocks */
.band-block {
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  border: 1px solid var(--grey-200);
}

.band-block--low { border-top: 3px solid #22c55e; }
.band-block--mid { border-top: 3px solid var(--blue-accent); }
.band-block--high { border-top: 3px solid #f59e0b; }

.band-block__label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.band-block--low .band-block__label { color: #16a34a; }
.band-block--mid .band-block__label { color: var(--blue-dark); }
.band-block--high .band-block__label { color: #d97706; }

.band-block h4 { font-size: 1rem; margin-bottom: 0.5rem; }
.band-block p { font-size: 0.875rem; }

/* --- Print --- */
@media print {
  .nav, .nav__mobile, .footer { display: none; }
  body { font-size: 12pt; }
  .section { padding: 1.5rem 0; }
}

/* --- Responsive Table Wrapper --- */
.table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--grey-200);
}

/* scroll to top */
.scroll-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  width: 40px;
  height: 40px;
  background: var(--blue-accent);
  color: white;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
  z-index: 50;
}

.scroll-top.visible { opacity: 1; pointer-events: auto; }
.scroll-top svg { width: 18px; height: 18px; }