/* =========================================================
   1. CSS Custom Properties
   ========================================================= */
:root {
  --bg-primary:   #0e0b14;
  --bg-surface:   #13111e;
  --bg-elevated:  #1c1830;
  --accent:       #8b5cf6;
  --accent-hover: #7c3aed;
  --accent-warm:  #f0a500;
  --text-primary: #e8eaf0;
  --text-muted:   #7a8499;
  --border:       #231f33;
  --success:      #2ecc71;
  --danger:       #e05252;
  --radius:       4px;
  --transition:   0.2s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cg stroke='rgba(139,92,246,0.15)' stroke-width='1' fill='none'%3E%3C!-- horizontal traces --%3E%3Cline x1='0' y1='30' x2='40' y2='30'/%3E%3Cline x1='80' y1='30' x2='120' y2='30'/%3E%3Cline x1='0' y1='90' x2='30' y2='90'/%3E%3Cline x1='90' y1='90' x2='120' y2='90'/%3E%3C!-- vertical traces --%3E%3Cline x1='40' y1='0' x2='40' y2='30'/%3E%3Cline x1='80' y1='30' x2='80' y2='60'/%3E%3Cline x1='30' y1='90' x2='30' y2='120'/%3E%3Cline x1='90' y1='60' x2='90' y2='90'/%3E%3C!-- L-turn connectors --%3E%3Cline x1='40' y1='30' x2='40' y2='60'/%3E%3Cline x1='40' y1='60' x2='80' y2='60'/%3E%3Cline x1='90' y1='60' x2='90' y2='90'/%3E%3Cline x1='30' y1='90' x2='90' y2='90'/%3E%3C!-- component box --%3E%3Crect x='52' y='22' width='16' height='10' rx='1'/%3E%3C!-- solder pads --%3E%3Ccircle cx='40' cy='30' r='2.5' fill='rgba(139,92,246,0.2)' stroke='rgba(139,92,246,0.25)'/%3E%3Ccircle cx='80' cy='30' r='2.5' fill='rgba(139,92,246,0.2)' stroke='rgba(139,92,246,0.25)'/%3E%3Ccircle cx='40' cy='60' r='2.5' fill='rgba(139,92,246,0.2)' stroke='rgba(139,92,246,0.25)'/%3E%3Ccircle cx='80' cy='60' r='2.5' fill='rgba(139,92,246,0.2)' stroke='rgba(139,92,246,0.25)'/%3E%3Ccircle cx='30' cy='90' r='2.5' fill='rgba(139,92,246,0.2)' stroke='rgba(139,92,246,0.25)'/%3E%3Ccircle cx='90' cy='90' r='2.5' fill='rgba(139,92,246,0.2)' stroke='rgba(139,92,246,0.25)'/%3E%3C/g%3E%3C/svg%3E");
  background-size: 120px 120px;
  color: var(--text-primary);
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}
a:hover { color: var(--accent-hover); }

ul { list-style: none; }

/* =========================================================
   3. Typography
   ========================================================= */
h1, h2, h3, h4 {
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--text-primary);
}

h1 { font-size: clamp(2rem, 5vw, 3.2rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2rem); }
h3 { font-size: 1.2rem; }

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

code, .mono {
  font-family: 'JetBrains Mono', 'Fira Code', ui-monospace, monospace;
  font-size: 0.875em;
  color: var(--accent);
  background: var(--bg-elevated);
  padding: 0.1em 0.4em;
  border-radius: 3px;
}

/* =========================================================
   4. Layout Utilities
   ========================================================= */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 5rem 0;
}

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

.section__header {
  margin-bottom: 3rem;
}

.section__header h2 {
  margin-bottom: 0.75rem;
}

.section__header p {
  max-width: 600px;
  font-size: 1.05rem;
}

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

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 3rem 0;
}

/* =========================================================
   5. Navigation
   ========================================================= */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 15, 20, 0.92);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav__logo {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.logo__spark { color: var(--accent); }
.logo__line  { color: var(--text-primary); }
.logo__eng   { color: #c4b5fd; }

.nav__links {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav__links a {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition);
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
}

.nav__links a:hover,
.nav__links a.active {
  color: var(--text-primary);
  border-bottom-color: var(--accent);
}

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav__toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav__toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav__toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}
.nav__toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* =========================================================
   6. Buttons
   ========================================================= */
.btn {
  display: inline-block;
  padding: 0.75rem 1.75rem;
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
  text-decoration: none;
}

.btn--primary {
  background: var(--accent);
  color: #0d0f14;
  border-color: var(--accent);
}
.btn--primary:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  color: #0d0f14;
}

.btn--outline {
  background: transparent;
  color: var(--text-primary);
  border-color: var(--border);
}
.btn--outline:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* =========================================================
   7. Hero Section
   ========================================================= */
.hero {
  min-height: calc(100vh - 64px);
  display: flex;
  align-items: center;
  padding: 5rem 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: radial-gradient(ellipse at 60% 40%, rgba(139,92,246,0.12) 0%, transparent 70%);
  pointer-events: none;
}

.hero__content {
  position: relative;
  max-width: 780px;
}

.hero__eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  margin-bottom: 1.25rem;
  border: 1px solid rgba(139,92,246,0.3);
  padding: 0.3rem 0.75rem;
  border-radius: 2px;
}

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

.hero__line {
  display: block;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-warm));
  margin: 1.5rem 0;
  border-radius: 2px;
}

.hero__sub {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 580px;
  margin-bottom: 2.5rem;
  line-height: 1.7;
}

.hero__actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

/* =========================================================
   8. Cards
   ========================================================= */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.card:hover {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--accent), 0 4px 24px rgba(139,92,246,0.12);
}

.card__icon {
  font-size: 2rem;
  margin-bottom: 1.25rem;
  line-height: 1;
}

.card h3 {
  margin-bottom: 0.75rem;
}

.card p {
  font-size: 0.95rem;
  margin-bottom: 1.25rem;
}

.card .card__link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.card .card__link::after {
  content: '→';
  transition: transform var(--transition);
}

.card:hover .card__link::after {
  transform: translateX(4px);
}

/* Project cards with sector tag */
.card__tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent-warm);
  border: 1px solid rgba(240,165,0,0.3);
  padding: 0.2rem 0.6rem;
  border-radius: 2px;
  margin-bottom: 1rem;
}

/* =========================================================
   9. Section Styles
   ========================================================= */

/* Why Choose Us */
.why-item {
  text-align: left;
}

.why-item__number {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 0.75rem;
  font-family: 'JetBrains Mono', ui-monospace, monospace;
}

.why-item h3 {
  margin-bottom: 0.5rem;
}

/* CTA Banner */
.cta-banner {
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 4rem 0;
  text-align: center;
}

.cta-banner h2 {
  margin-bottom: 0.75rem;
}

.cta-banner p {
  margin-bottom: 2rem;
  font-size: 1.05rem;
}

/* Page Header (inner pages) */
.page-header {
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  padding: 3.5rem 0;
}

.page-header h1 {
  margin-bottom: 0.75rem;
}

/* Services page */
.service-block {
  padding: 4rem 0;
}

.service-block__intro {
  max-width: 700px;
  margin-bottom: 2rem;
}

.service-block h2 {
  margin-bottom: 1rem;
}

.service-list {
  margin: 1.5rem 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.service-list li {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.service-list li::before {
  content: '▸';
  color: var(--accent);
  flex-shrink: 0;
  margin-top: 0.05em;
}

.standards-box {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-top: 2rem;
}

.standards-box h4 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.standards-box ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.standards-box li {
  font-family: 'JetBrains Mono', ui-monospace, monospace;
  font-size: 0.8rem;
  color: var(--text-muted);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  padding: 0.25rem 0.6rem;
  border-radius: 2px;
}

/* About page */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 4rem;
  align-items: start;
}

.about-avatar {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 3rem;
  text-align: center;
}

.about-avatar__initials {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-warm));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: #0d0f14;
  margin: 0 auto 1.25rem;
}

.about-avatar h3 {
  margin-bottom: 0.25rem;
}

.about-avatar p {
  font-size: 0.875rem;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.25rem;
}

.skill-tag {
  font-size: 0.75rem;
  font-family: 'JetBrains Mono', ui-monospace, monospace;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  padding: 0.25rem 0.6rem;
  border-radius: 2px;
  color: var(--text-muted);
}

.about-text h2 { margin-bottom: 1rem; }
.about-text p  { margin-bottom: 1.25rem; }

/* Project disclaimer */
.disclaimer {
  font-size: 0.8rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  margin-top: 1rem;
  font-style: italic;
}

/* =========================================================
   10. Forms & Alerts
   ========================================================= */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 4rem;
  align-items: start;
}

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

label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

label .optional {
  color: var(--text-muted);
  font-weight: 400;
}

input[type="text"],
input[type="email"],
input[type="tel"],
select,
textarea {
  width: 100%;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.95rem;
  padding: 0.75rem 1rem;
  transition: border-color var(--transition), box-shadow var(--transition);
  appearance: none;
  -webkit-appearance: none;
}

input::placeholder,
textarea::placeholder {
  color: var(--text-muted);
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(139,92,246,0.15);
}

select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%237a8499' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  padding-right: 2.5rem;
}

textarea {
  resize: vertical;
  min-height: 140px;
}

.field-error {
  display: block;
  font-size: 0.8rem;
  color: var(--danger);
  margin-top: 0.4rem;
}

input.has-error,
select.has-error,
textarea.has-error {
  border-color: var(--danger);
}

.alert {
  padding: 1rem 1.25rem;
  border-radius: var(--radius);
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.alert--success {
  background: rgba(46,204,113,0.1);
  border: 1px solid rgba(46,204,113,0.3);
  color: var(--success);
}

.alert--error {
  background: rgba(224,82,82,0.1);
  border: 1px solid rgba(224,82,82,0.3);
  color: var(--danger);
}

/* Contact info sidebar */
.contact-info {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
}

.contact-info h3 {
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.contact-info__item {
  display: flex;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
  align-items: flex-start;
}

.contact-info__icon {
  font-size: 1.1rem;
  flex-shrink: 0;
  margin-top: 0.1em;
}

.contact-info__label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.2rem;
}

.contact-info__value {
  font-size: 0.9rem;
  color: var(--text-primary);
}

/* =========================================================
   11. Footer
   ========================================================= */
.footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  padding: 3rem 0 1.5rem;
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer__brand h3 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

.footer__brand h3 span { color: var(--accent); }

.footer__brand p {
  font-size: 0.875rem;
  max-width: 280px;
}

.footer__col h4 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

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

.footer__col a {
  color: var(--text-muted);
  font-size: 0.875rem;
}

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

.footer__bottom {
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.footer__bottom p {
  font-size: 0.8rem;
}

/* =========================================================
   12. Media Queries
   ========================================================= */
@media (max-width: 900px) {
  .about-grid {
    grid-template-columns: 1fr;
  }

  .about-avatar {
    order: -1;
    max-width: 360px;
  }

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

  .footer__brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 768px) {
  .nav__links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg-surface);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    gap: 0;
    padding: 0.5rem 0;
  }

  .nav__links.nav__links--open {
    display: flex;
  }

  .nav__links a {
    padding: 0.875rem 1.5rem;
    border-bottom: none;
    border-left: 3px solid transparent;
    width: 100%;
  }

  .nav__links a.active,
  .nav__links a:hover {
    border-left-color: var(--accent);
    border-bottom: none;
  }

  .nav__toggle { display: flex; }

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

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

  .hero__actions {
    flex-direction: column;
  }

  .hero__actions .btn {
    text-align: center;
  }

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

  .footer__bottom {
    flex-direction: column;
    text-align: center;
  }
}