/* ============================================================
   Twin Era Technology — Stylesheet v2
   "Field Engineering" design system
   Space Grotesk (display) / Inter (body) / JetBrains Mono (data)
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;600;700&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

:root {
  --tet-blue:       #2C5F9E;
  --tet-blue-light: #4C7EC0;
  --tet-blue-dark:  #1E4676;
  --tet-orange:     #E8933A;
  --tet-orange-lt:  #F5B872;
  --tet-green:      #3FAE7A;
  --tet-yellow:     #F5B872;
  --tet-violet:     #7C6FC4;
  --tet-navy:       #0A1628;
  --tet-slate:      #132338;

  --bg-primary:     #F6F4EE;
  --bg-secondary:   #FFFFFF;
  --bg-card:        #FFFEFB;
  --bg-nav:         rgba(246,244,238,0.90);
  --text-primary:   #161F2B;
  --text-secondary: #4E5560;
  --text-muted:     #838B96;
  --border-color:   #E2DFD4;
  --shadow-color:   rgba(22,31,43,0.08);
  --hero-overlay:   rgba(10,22,40,0.5);

  --grad-primary:   linear-gradient(135deg, var(--tet-blue), var(--tet-blue-dark));
  --grad-orange:    linear-gradient(135deg, var(--tet-orange), var(--tet-yellow));
  --grad-green:     linear-gradient(135deg, var(--tet-green), #2C8F63);
  --grad-hero:      linear-gradient(150deg, #0A1628 0%, #0D2038 55%, #14263B 100%);

  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;
  --radius-xl: 14px;

  --transition: 0.25s cubic-bezier(0.4,0,0.2,1);
  --font-disp: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

[data-theme="dark"] {
  --bg-primary:     #0A1628;
  --bg-secondary:   #0D1E33;
  --bg-card:        #132338;
  --bg-nav:         rgba(10,22,40,0.92);
  --text-primary:   #F2F1EA;
  --text-secondary: #B9C4D6;
  --text-muted:     #6E7F98;
  --border-color:   rgba(255,255,255,0.10);
  --shadow-color:   rgba(0,0,0,0.35);
  --hero-overlay:   rgba(0,0,0,0.4);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  transition: background-color var(--transition), color var(--transition);
  overflow-x: hidden;
  line-height: 1.7;
  font-size: 15.5px;
}

h1,h2,h3,h4,h5,h6 {
  font-family: var(--font-disp);
  font-weight: 600;
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--text-primary);
}

.display-hero { font-size: clamp(2.3rem, 5vw, 4rem); font-weight: 600; letter-spacing: -0.02em; color:#fff; }
.section-title { font-size: clamp(1.9rem, 3.4vw, 2.6rem); position: relative; }
.section-subtitle { font-size: 1.05rem; color: var(--text-secondary); max-width: 600px; margin: 0 auto; }
.font-mono { font-family: var(--font-mono); }

.text-blue   { color: var(--tet-blue) !important; }
.text-orange { color: var(--tet-orange) !important; }
.text-green  { color: var(--tet-green) !important; }
.text-violet { color: var(--tet-violet) !important; }
.bg-blue   { background: var(--tet-blue) !important; }
.bg-orange { background: var(--tet-orange) !important; }
.bg-green  { background: var(--tet-green) !important; }

.gradient-text {
  background: linear-gradient(100deg, var(--tet-orange), var(--tet-blue));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.gradient-text-orange {
  background: var(--grad-orange);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--tet-orange);
  display: inline-block;
  margin-bottom: 0.75rem;
}
.divider-accent { width: 48px; height: 3px; background: var(--tet-orange); border-radius: 2px; margin: 0.75rem auto; }
.divider-left { margin-left: 0; }

.section-pad { padding: 88px 0; }
.section-pad-sm { padding: 48px 0; }

.navbar-tet {
  background: var(--bg-nav);
  backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  padding: 0.85rem 0;
  transition: all var(--transition);
  position: sticky; top: 0; z-index: 1000;
}
.navbar-tet.scrolled { box-shadow: 0 4px 24px var(--shadow-color); }

.tet-logo { display: flex; align-items: center; gap: 12px; text-decoration: none !important; }
.tet-logo-mark { width: 40px; height: 40px; position: relative; flex-shrink: 0; }
.tet-logo-text { display: flex; flex-direction: column; line-height: 1; }
.tet-logo-abbr { font-family: var(--font-mono); font-weight: 700; font-size: 1.15rem; letter-spacing: 0.04em; color: var(--text-primary); }
.tet-logo-name { font-family: var(--font-body); font-size: 0.66rem; font-weight: 600; color: var(--text-muted); letter-spacing: 0.03em; text-transform: uppercase; }

.nav-link-tet {
  font-family: var(--font-body); font-weight: 500; font-size: 0.92rem;
  color: var(--text-secondary) !important; letter-spacing: 0.01em;
  padding: 0.5rem 1rem !important; position: relative; transition: color var(--transition);
  text-decoration: none;
}
.nav-link-tet::after {
  content: ''; position: absolute; bottom: 0; left: 50%; transform: translateX(-50%);
  width: 0; height: 2px; background: var(--tet-orange); transition: width var(--transition); border-radius: 2px;
}
.nav-link-tet:hover, .nav-link-tet.active { color: var(--text-primary) !important; }
.nav-link-tet:hover::after, .nav-link-tet.active::after { width: 60%; }

.theme-toggle {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-sm);
  padding: 7px 14px; cursor: pointer; display: flex; align-items: center; gap: 6px;
  font-size: 0.8rem; font-family: var(--font-mono); color: var(--text-secondary); transition: all var(--transition);
}
.theme-toggle:hover { border-color: var(--tet-orange); color: var(--tet-orange); }
.theme-toggle .icon { font-size: 0.95rem; }
.navbar-toggler-tet { background: none; border: 1px solid var(--border-color); border-radius: var(--radius-sm); padding: 6px 10px; color: var(--text-primary); }

.btn-tet {
  font-family: var(--font-body); font-weight: 600; font-size: 0.92rem; letter-spacing: 0.01em;
  padding: 13px 26px; border-radius: var(--radius-sm); border: none; cursor: pointer;
  transition: all var(--transition); text-decoration: none; display: inline-flex; align-items: center; gap: 8px;
}
.btn-tet-primary { background: var(--tet-orange); color: var(--tet-navy); }
.btn-tet-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(232,147,58,0.35); color: var(--tet-navy); }
.btn-tet-secondary { background: transparent; color: var(--text-primary); border: 1px solid var(--border-color); }
.btn-tet-secondary:hover { border-color: var(--tet-orange); color: var(--tet-orange); transform: translateY(-2px); }
.btn-tet-orange { background: var(--tet-orange); color: var(--tet-navy); }
.btn-tet-orange:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(232,147,58,0.35); color: var(--tet-navy); }

.hero-section { background: var(--grad-hero); min-height: 88vh; display: flex; align-items: center; position: relative; overflow: hidden; }
.hero-bg-shapes { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.hero-grid-lines {
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,0.06) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 75% 65% at 50% 30%, black, transparent);
}
.hero-shape { position: absolute; border-radius: 50%; filter: blur(90px); opacity: 0.18; }
.shape-1 { width: 480px; height: 480px; background: var(--tet-blue); top: -120px; right: -100px; animation: float1 9s ease-in-out infinite; }
.shape-2 { width: 340px; height: 340px; background: var(--tet-orange); bottom: -90px; left: 8%; animation: float2 11s ease-in-out infinite; }
.shape-3 { width: 260px; height: 260px; background: var(--tet-green); top: 35%; left: 42%; animation: float1 13s ease-in-out infinite reverse; }
@keyframes float1 { 0%,100% { transform: translate(0,0) scale(1);} 50% { transform: translate(20px,-30px) scale(1.05);} }
@keyframes float2 { 0%,100% { transform: translate(0,0) scale(1);} 50% { transform: translate(-20px,20px) scale(1.08);} }

.hero-badge { display: inline-flex; align-items: center; gap: 10px; font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--tet-orange); margin-bottom: 1.5rem; }
.hero-badge .dot { width: 7px; height: 7px; background: var(--tet-green); border-radius: 50%; box-shadow: 0 0 0 4px rgba(63,174,122,0.2); animation: pulse-dot 2s infinite; }
@keyframes pulse-dot { 0%,100% { opacity:1; transform:scale(1);} 50% { opacity:0.6; transform:scale(1.3);} }

.hero-stats { display: flex; gap: 2.2rem; flex-wrap: wrap; margin-top: 2.2rem; padding-top: 1.6rem; border-top: 1px solid rgba(255,255,255,0.12); }
.hero-stat { display: flex; flex-direction: column; font-family: var(--font-mono); }
.hero-stat .num { font-size: 1.7rem; font-weight: 600; color: #fff; }
.hero-stat .label { font-size: 0.68rem; color: #7C8CA6; letter-spacing: 0.04em; text-transform: uppercase; margin-top: 2px; }
.hero-visual { display: flex; justify-content: center; }

.card-tet, .service-card, .value-card, .team-card, .contact-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-md);
  padding: 1.75rem; position: relative; transition: all var(--transition);
}
.card-tet::before, .service-card::before, .value-card::before, .team-card::before {
  content:''; position:absolute; top:-1px; left:-1px; width:12px; height:12px;
  border-top: 1.5px solid var(--tet-orange); border-left: 1.5px solid var(--tet-orange);
  opacity: 0; transition: opacity var(--transition);
}
.card-tet::after, .service-card::after, .value-card::after, .team-card::after {
  content:''; position:absolute; bottom:-1px; right:-1px; width:12px; height:12px;
  border-bottom: 1.5px solid var(--tet-orange); border-right: 1.5px solid var(--tet-orange);
  opacity: 0; transition: opacity var(--transition);
}
.card-tet:hover, .service-card:hover, .value-card:hover, .team-card:hover { transform: translateY(-3px); box-shadow: 0 12px 28px var(--shadow-color); }
.card-tet:hover::before, .service-card:hover::before, .value-card:hover::before, .team-card:hover::before,
.card-tet:hover::after, .service-card:hover::after, .value-card:hover::after, .team-card:hover::after { opacity: 1; }

.card-icon { width: 52px; height: 52px; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; margin-bottom: 1rem; }
.icon-blue   { background: rgba(44,95,158,0.12); }
.icon-orange { background: rgba(232,147,58,0.14); }
.icon-green  { background: rgba(63,174,122,0.14); }
.icon-violet { background: rgba(124,111,196,0.14); }

.service-card { padding: 0; overflow: hidden; }
.service-card-header { padding: 1.75rem 1.75rem 1.25rem; border-bottom: 1px solid var(--border-color); position: relative; }
.service-card-body { padding: 1.25rem 1.75rem 1.75rem; }
.service-number { font-family: var(--font-mono); font-size: 0.72rem; color: var(--text-muted); letter-spacing: 0.08em; display:block; margin-bottom: 0.75rem; }
.blue-head { border-top: 3px solid var(--tet-blue); }
.orange-head { border-top: 3px solid var(--tet-orange); }
.green-head { border-top: 3px solid var(--tet-green); }
.service-feature { display: flex; align-items: center; gap: 10px; padding: 8px 0; font-size: 0.88rem; color: var(--text-secondary); border-bottom: 1px dashed var(--border-color); }
.service-feature:last-of-type { border-bottom: none; }
.check { width: 18px; height: 18px; border-radius: 3px; display: flex; align-items: center; justify-content: center; font-size: 0.68rem; flex-shrink: 0; color: #fff; }
.check-blue { background: var(--tet-blue); }
.check-orange { background: var(--tet-orange); }
.check-green { background: var(--tet-green); }

.stats-section { background: var(--tet-navy); padding: 64px 0; position: relative; }
.stat-card { font-family: var(--font-mono); }
.stat-number { font-size: clamp(2rem, 4vw, 2.6rem); font-weight: 700; color: #fff; display: block; }
.stat-label { font-size: 0.75rem; color: #8497B3; letter-spacing: 0.04em; text-transform: uppercase; margin-top: 6px; }

.why-item { display: flex; gap: 1rem; align-items: flex-start; padding: 0.5rem 0; }

.portfolio-filters { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 2.5rem; }
.filter-btn { font-family: var(--font-mono); font-size: 0.78rem; background: var(--bg-card); border: 1px solid var(--border-color); color: var(--text-secondary); padding: 9px 18px; border-radius: var(--radius-sm); cursor: pointer; transition: all var(--transition); }
.filter-btn.active, .filter-btn:hover { border-color: var(--tet-orange); color: var(--tet-orange); }
.portfolio-thumb { height: 180px; display: flex; align-items: center; justify-content: center; }
.sw-bg  { background: linear-gradient(135deg, rgba(44,95,158,0.25), rgba(44,95,158,0.08)); }
.tel-bg { background: linear-gradient(135deg, rgba(232,147,58,0.25), rgba(232,147,58,0.08)); }
.sol-bg { background: linear-gradient(135deg, rgba(63,174,122,0.25), rgba(63,174,122,0.08)); }
.portfolio-cat-badge { font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.04em; text-transform: uppercase; padding: 4px 10px; border-radius: 3px; font-weight: 600; }
.badge-sw  { background: rgba(44,95,158,0.14); color: var(--tet-blue); }
.badge-tel { background: rgba(232,147,58,0.16); color: var(--tet-orange); }
.badge-sol { background: rgba(63,174,122,0.16); color: var(--tet-green); }

.team-card { text-align: center; }
.team-avatar { width: 72px; height: 72px; border-radius: var(--radius-sm); margin: 0 auto 1rem; display: flex; align-items: center; justify-content: center; color: #fff; font-family: var(--font-mono); font-weight: 700; font-size: 1.2rem; }
.team-role { font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--tet-orange); margin-bottom: 0.4rem; }

.timeline { position: relative; padding-left: 28px; border-left: 1px solid var(--border-color); }
.timeline-item { position: relative; padding-bottom: 2.2rem; }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-dot { position: absolute; left: -33px; top: 4px; width: 10px; height: 10px; border-radius: 50%; }
.timeline-year { font-family: var(--font-mono); font-weight: 700; font-size: 0.85rem; margin-bottom: 0.3rem; letter-spacing: 0.02em; }

.highlight-tag, .tech-tag { display: inline-block; font-family: var(--font-mono); font-size: 0.76rem; padding: 6px 14px; border: 1px solid var(--border-color); border-radius: var(--radius-sm); color: var(--text-secondary); background: var(--bg-card); margin: 0 6px 6px 0; }

.page-hero { background: var(--grad-hero); padding: 130px 0 70px; position: relative; }
.breadcrumb-tet .breadcrumb { font-family: var(--font-mono); font-size: 0.78rem; margin-bottom: 0; }
.breadcrumb-tet a { color: #8497B3; text-decoration: none; }
.breadcrumb-tet .active { color: var(--tet-orange); }

.contact-card { padding: 2.2rem; }
.contact-info-item { display: flex; gap: 1rem; align-items: flex-start; padding: 1rem 0; border-bottom: 1px solid var(--border-color); }
.contact-info-item:last-child { border-bottom: none; }
.contact-icon { width: 44px; height: 44px; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }

.form-tet label { font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.04em; text-transform: uppercase; color: var(--text-muted); margin-bottom: 6px; display: block; }
.form-tet .form-control, .form-tet .form-select { background: var(--bg-primary); border: 1px solid var(--border-color); border-radius: var(--radius-sm); padding: 11px 14px; font-size: 0.92rem; color: var(--text-primary); width: 100%; font-family: var(--font-body); transition: border-color var(--transition); }
.form-tet .form-control:focus, .form-tet .form-select:focus { outline: none; border-color: var(--tet-orange); box-shadow: 0 0 0 3px rgba(232,147,58,0.12); }

.alert-tet { padding: 12px 16px; border-radius: var(--radius-sm); font-size: 0.88rem; }
.alert-success-tet { background: rgba(63,174,122,0.12); color: var(--tet-green); border: 1px solid rgba(63,174,122,0.3); }
.alert-danger-tet { background: rgba(220,80,80,0.12); color: #D65050; border: 1px solid rgba(220,80,80,0.3); }

.accordion-item { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-sm) !important; margin-bottom: 10px; overflow: hidden; }
.accordion-button { background: var(--bg-card); color: var(--text-primary); font-family: var(--font-body); font-weight: 600; font-size: 0.92rem; }
.accordion-button:not(.collapsed) { background: var(--bg-card); color: var(--tet-orange); box-shadow: none; }
.accordion-button:focus { box-shadow: none; border-color: var(--border-color); }
.accordion-body { color: var(--text-secondary); font-size: 0.88rem; }

.newsletter-strip { background: var(--tet-navy); padding: 56px 0; }
.newsletter-strip h3 { color: #fff; }
.newsletter-input-group { display: flex; max-width: 440px; margin: 1.5rem auto 0; gap: 10px; }
.newsletter-input-group input { flex: 1; padding: 12px 16px; border-radius: var(--radius-sm); border: 1px solid rgba(255,255,255,0.15); background: rgba(255,255,255,0.06); color: #fff; font-family: var(--font-body); font-size: 0.9rem; }
.newsletter-input-group input::placeholder { color: #6E7F98; }
.newsletter-input-group button { font-family: var(--font-mono); font-weight: 600; font-size: 0.85rem; background: var(--tet-orange); color: var(--tet-navy); border: none; padding: 0 20px; border-radius: var(--radius-sm); cursor: pointer; }

.footer-tet { background: #08111F; color: #B9C4D6; padding: 72px 0 0; }
.footer-brand p { font-size: 0.88rem; color: #7C8CA6; margin: 1rem 0 1.25rem; max-width: 320px; line-height: 1.7; }
.footer-heading { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: #fff; margin-bottom: 1.1rem; }
.footer-links { list-style: none; }
.footer-links li { margin-bottom: 0.65rem; }
.footer-links a { color: #7C8CA6; text-decoration: none; font-size: 0.88rem; transition: color var(--transition); }
.footer-links a:hover { color: var(--tet-orange); }
.social-links { display: flex; gap: 10px; }
.social-link { width: 38px; height: 38px; border-radius: var(--radius-sm); background: rgba(255,255,255,0.06); display: flex; align-items: center; justify-content: center; color: #B9C4D6; text-decoration: none; transition: all var(--transition); }
.social-link:hover { background: var(--tet-orange); color: var(--tet-navy); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding: 22px 0; margin-top: 48px; }
.footer-bottom p { font-size: 0.8rem; color: #5D7191; margin: 0; }

.preloader { position: fixed; inset: 0; background: var(--tet-navy); z-index: 9999; display: flex; align-items: center; justify-content: center; transition: opacity 0.5s, visibility 0.5s; }
.preloader.hidden { opacity: 0; visibility: hidden; }
.preloader-bar { width: 140px; height: 3px; background: rgba(255,255,255,0.1); border-radius: 2px; margin-top: 18px; overflow: hidden; }
.preloader-fill { height: 100%; background: var(--tet-orange); width: 0%; animation: loadbar 1.5s ease-in-out forwards; }
@keyframes loadbar { to { width: 100%; } }

.scroll-top { position: fixed; bottom: 24px; right: 24px; width: 44px; height: 44px; border-radius: var(--radius-sm); background: var(--tet-orange); color: var(--tet-navy); border: none; display: flex; align-items: center; justify-content: center; opacity: 0; visibility: hidden; transform: translateY(10px); transition: all var(--transition); z-index: 900; cursor: pointer; }
.scroll-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }

.fade-in-up { opacity: 0; transform: translateY(16px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in-up.visible { opacity: 1; transform: translateY(0); }
.delay-1.visible { transition-delay: 0.08s; }
.delay-2.visible { transition-delay: 0.16s; }
.delay-3.visible { transition-delay: 0.24s; }
.delay-4.visible { transition-delay: 0.32s; }

.error-404 { min-height: 70vh; display: flex; align-items: center; justify-content: center; text-align: center; }
.error-code { font-family: var(--font-mono); font-size: clamp(4rem, 12vw, 8rem); font-weight: 700; color: var(--tet-orange); line-height: 1; }

@media (max-width: 991px) {
  .hero-section { min-height: auto; padding: 130px 0 60px; }
  .section-pad { padding: 60px 0; }
}