/* =========================================================================
   AIEngineers.in — Shared Design System
   Used by: courses.html, course-detail.html, city-hyderabad.html, about.html
   ========================================================================= */

:root{
  --navy:#0A0F1E; --navy-2:#111827; --navy-3:#1E293B; --navy-4:#334155;
  --indigo:#6366F1; --indigo-d:#4F46E5; --indigo-l:#EEF2FF; --indigo-xl:#C7D2FE;
  --emerald:#10B981; --emerald-l:#D1FAE5; --emerald-d:#065F46;
  --amber:#F59E0B; --amber-l:#FEF3C7; --amber-d:#92400E;
  --white:#fff;
  --gray-50:#F8FAFC; --gray-100:#F1F5F9; --gray-200:#E2E8F0;
  --gray-400:#94A3B8; --gray-600:#475569; --gray-800:#1E293B;
  --text-dark:#0F172A; --text-mid:#475569; --text-light:#94A3B8;
  --font-head:'Space Grotesk',system-ui,sans-serif;
  --font-body:'Inter',system-ui,sans-serif;
  --font-mono:'JetBrains Mono','Courier New',monospace;
  --radius-sm:8px; --radius-md:12px; --radius-lg:16px; --radius-xl:24px; --radius-pill:100px;
  --shadow-sm:0 1px 3px rgba(0,0,0,.08),0 2px 8px rgba(0,0,0,.06);
  --shadow-md:0 4px 16px rgba(0,0,0,.10);
  --shadow-indigo:0 4px 20px rgba(99,102,241,.35);
  --container:1200px; --section-pad:96px;
}

/* Resets */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;font-size:16px;-webkit-print-color-adjust:exact;print-color-adjust:exact}
body{font-family:var(--font-body);color:var(--text-dark);background:#fff;overflow-x:hidden;line-height:1.6;padding-top:68px;-webkit-font-smoothing:antialiased}
h1,h2,h3,h4,h5,h6{font-family:var(--font-head);font-weight:700;line-height:1.15}
a{text-decoration:none;color:inherit}
img{max-width:100%;height:auto;display:block}
button{cursor:pointer;border:none;background:none;font-family:inherit}
ul{list-style:none}
:focus-visible{outline:2px solid var(--indigo);outline-offset:3px;border-radius:4px}

/* Utilities */
.container{max-width:var(--container);margin:0 auto;padding:0 24px}
.section{padding:var(--section-pad) 0}
.section--dark{background:var(--navy-2)}
.section--gray{background:var(--gray-50)}
.section--navy{background:var(--navy)}
.section--indigo{background:var(--indigo-l)}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:14px 28px;border-radius:var(--radius-sm);font-family:var(--font-head);font-size:15px;font-weight:600;transition:all 200ms ease;cursor:pointer;border:none;white-space:nowrap;text-align:center}
.btn-sm{padding:10px 18px;font-size:13px}
.btn-lg{padding:18px 36px;font-size:17px}
.btn-primary{background:var(--indigo);color:#fff;box-shadow:var(--shadow-indigo)}
.btn-primary:hover{background:var(--indigo-d);transform:translateY(-1px);box-shadow:0 6px 24px rgba(99,102,241,.45)}
.btn-ghost{background:transparent;color:#fff;border:1.5px solid rgba(255,255,255,.3)}
.btn-ghost:hover{border-color:var(--indigo-xl);color:var(--indigo-xl);background:rgba(99,102,241,.1)}
.btn-outline{background:transparent;color:var(--indigo);border:1.5px solid var(--indigo)}
.btn-outline:hover{background:var(--indigo);color:#fff;box-shadow:var(--shadow-indigo)}
.btn-white{background:#fff;color:var(--indigo);box-shadow:var(--shadow-md)}
.btn-white:hover{background:var(--indigo-l);transform:translateY(-1px)}

/* Badges */
.badge{display:inline-flex;align-items:center;gap:4px;padding:4px 12px;border-radius:var(--radius-pill);font-size:12px;font-weight:600;letter-spacing:.03em;white-space:nowrap}
.badge-indigo{background:var(--indigo-l);color:var(--indigo)}
.badge-green{background:var(--emerald-l);color:var(--emerald-d)}
.badge-amber{background:var(--amber-l);color:var(--amber-d)}
.badge-cyan{background:#CCFBF1;color:#065F46}
.badge-dark{background:var(--navy-3);color:var(--indigo-xl);border:1px solid var(--indigo)}
.badge-hot{background:var(--amber-l);color:var(--amber-d);border:1px solid var(--amber)}
.badge-gray{background:var(--gray-100);color:var(--text-mid);border:1px solid var(--gray-200)}

/* Typography helpers */
.eyebrow{display:block;font-family:var(--font-body);font-size:12px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--indigo);margin-bottom:12px}
.eyebrow--white{color:var(--indigo-xl)}
.section-headline{font-size:clamp(30px,4vw,44px);font-weight:700;line-height:1.15;color:var(--text-dark);margin-bottom:16px}
.section-headline--white{color:#fff}
.section-sub{font-size:18px;color:var(--text-mid);line-height:1.75;max-width:600px;margin-bottom:48px}
.section-sub--white{color:var(--gray-400)}

/* Breadcrumb */
.breadcrumb{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--gray-400);margin-bottom:24px;flex-wrap:wrap}
.breadcrumb a{color:var(--gray-400);transition:color 150ms}
.breadcrumb a:hover{color:var(--indigo-xl)}
.breadcrumb i{width:12px;height:12px}
.crumb-current{color:#fff;font-weight:500}
.crumb-current--dark{color:var(--text-dark);font-weight:500}

/* Fade-up — invisible only while JS is active. If JS is disabled or errors, content stays visible. */
html.fx-on .fade-up{opacity:0;transform:translateY(24px);transition:opacity .5s ease,transform .5s ease}
html.fx-on .fade-up.visible{opacity:1;transform:translateY(0)}

/* Gradient text */
.gradient-text{background:linear-gradient(135deg,#818CF8 0%,#34D399 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}

/* Hero decorations */
.hero-grid-bg{position:absolute;inset:0;background-image:linear-gradient(rgba(99,102,241,.04) 1px,transparent 1px),linear-gradient(90deg,rgba(99,102,241,.04) 1px,transparent 1px);background-size:48px 48px;pointer-events:none}
.hero-glow-tr{position:absolute;top:-200px;right:-200px;width:500px;height:500px;border-radius:50%;background:radial-gradient(circle,rgba(99,102,241,.10) 0%,transparent 70%);pointer-events:none}
.hero-glow-bl{position:absolute;bottom:-150px;left:-150px;width:350px;height:350px;border-radius:50%;background:radial-gradient(circle,rgba(16,185,129,.06) 0%,transparent 70%);pointer-events:none}

/* ========== NAV ========== */
.site-nav{position:fixed;top:0;left:0;right:0;z-index:1000;height:68px;background:rgba(10,15,30,.95);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);border-bottom:1px solid rgba(255,255,255,.07);transition:background 300ms ease,border-color 300ms ease,box-shadow 300ms ease}
.site-nav.scrolled{background:rgba(255,255,255,.97);border-bottom:1px solid var(--gray-200);box-shadow:var(--shadow-sm)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:68px;gap:24px}
.nav-logo{display:flex;align-items:baseline;gap:1px;flex-shrink:0}
.logo-ai{font-family:var(--font-head);font-size:22px;font-weight:700;color:var(--indigo)}
.logo-eng{font-family:var(--font-head);font-size:22px;font-weight:700;color:#fff;transition:color 300ms}
.logo-dot{font-size:14px;font-weight:400;color:var(--gray-400)}
.site-nav.scrolled .logo-eng{color:var(--text-dark)}

.nav-links{display:flex;align-items:center;gap:4px;list-style:none;flex:1;justify-content:center}
.nav-link{display:inline-flex;align-items:center;gap:4px;padding:8px 12px;border-radius:var(--radius-sm);font-size:14px;font-weight:500;color:rgba(255,255,255,.8);transition:color 200ms,background 200ms;cursor:pointer;background:none;border:none;font-family:var(--font-body)}
.nav-link:hover{color:#fff;background:rgba(255,255,255,.06)}
.nav-link.active{color:var(--indigo-xl)}
.site-nav.scrolled .nav-link{color:var(--text-mid)}
.site-nav.scrolled .nav-link:hover{color:var(--text-dark);background:var(--gray-100)}
.site-nav.scrolled .nav-link.active{color:var(--indigo)}
.nav-chevron{width:14px;height:14px;transition:transform 200ms;display:inline-block}
.nav-has-dropdown:hover .nav-chevron,.nav-has-dropdown .nav-dropdown-trigger[aria-expanded="true"] .nav-chevron{transform:rotate(180deg)}

.nav-has-dropdown{position:relative}
.nav-dropdown{position:absolute;top:100%;left:50%;transform:translateX(-50%) translateY(0);background:#fff;border:1px solid var(--gray-200);border-radius:16px;padding:14px 12px 12px;box-shadow:0 18px 40px rgba(15,23,42,.12);opacity:0;pointer-events:none;transition:opacity 200ms ease,transform 200ms ease;min-width:360px;z-index:1100}
.nav-dropdown--wide{min-width:460px}
.nav-has-dropdown:hover .nav-dropdown{opacity:1;pointer-events:auto;transform:translateX(-50%) translateY(0)}
.dropdown-list{display:flex;flex-direction:column;gap:8px}
.dropdown-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.dropdown-link{display:flex;align-items:center;justify-content:space-between;padding:12px 14px;border-radius:12px;font-size:14px;font-weight:500;color:var(--text-dark)!important;transition:all 160ms ease;gap:8px;border:1px solid var(--gray-200);background:#fff;box-shadow:0 1px 0 rgba(15,23,42,.02)}
.dropdown-link:hover{background:var(--indigo-l);color:var(--indigo)!important;border-color:rgba(99,102,241,.28);transform:translateY(-1px);box-shadow:0 10px 22px rgba(99,102,241,.08)}
.dropdown-city{display:flex;align-items:center;justify-content:space-between;padding:11px 14px;border-radius:12px;font-size:14px;font-weight:500;color:var(--text-dark);transition:all 160ms ease;gap:8px;border:1px solid var(--gray-200);background:#fff}
.dropdown-city:hover{background:var(--indigo-l);color:var(--indigo);border-color:rgba(99,102,241,.28);transform:translateY(-1px)}
.dropdown-mini{font-size:10px;padding:2px 8px;background:var(--gray-100);color:var(--gray-600);border-radius:999px;font-weight:600;letter-spacing:.02em}
.nav-item-icon{width:14px;height:14px;flex:0 0 auto;color:var(--indigo);opacity:.7}

.nav-right{display:flex;align-items:center;gap:16px;flex-shrink:0}
.nav-demo-link{font-size:14px;font-weight:500;color:var(--indigo-xl);transition:color 200ms;white-space:nowrap}
.nav-demo-link:hover{color:#fff}
.site-nav.scrolled .nav-demo-link{color:var(--indigo)}
.nav-divider{width:1px;height:20px;background:rgba(255,255,255,.15)}
.site-nav.scrolled .nav-divider{background:var(--gray-200)}

.nav-hamburger{display:none;color:#fff;padding:8px;align-items:center;justify-content:center;background:none;border:none}
.nav-hamburger i{width:24px;height:24px}
.site-nav.scrolled .nav-hamburger{color:var(--text-dark)}

.mobile-overlay{position:fixed;inset:0;z-index:1100;background:var(--navy);padding:0 24px 32px;display:flex;flex-direction:column;transform:translateX(100%);transition:transform 350ms cubic-bezier(.4,0,.2,1);overflow-y:auto}
.mobile-overlay.open{transform:translateX(0)}
.mobile-overlay-head{display:flex;align-items:center;justify-content:space-between;height:68px;border-bottom:1px solid var(--navy-4);margin-bottom:24px;flex-shrink:0}
.mobile-overlay-head button{background:none;border:none;cursor:pointer;padding:8px}
.mobile-nav-links{flex:1}
.mobile-nav-links a,.mobile-cities summary{display:flex;align-items:center;justify-content:space-between;padding:16px 0;font-size:18px;font-weight:600;color:#fff;border-bottom:1px solid rgba(255,255,255,.07);cursor:pointer;list-style:none}
.mobile-cities summary{font-family:inherit}
.mobile-cities summary i{width:18px;height:18px}
.mobile-cities-list{padding:8px 0 8px 16px}
.mobile-cities-list a{padding:10px 0;font-size:15px;color:var(--gray-400);border-bottom:none;display:block}
.mobile-cities-list a:hover{color:#fff}
.mobile-overlay-ctas{margin-top:24px;flex-shrink:0}

@media(max-width:1023px){.nav-links,.nav-right .btn,.nav-demo-link,.nav-divider{display:none}.nav-hamburger{display:flex}}

/* ========== FOOTER ========== */
.site-footer{background:var(--navy);padding:80px 0 0;color:var(--gray-400)}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:48px;padding-bottom:64px}
.footer-tagline{font-size:14px;color:var(--gray-400);line-height:1.7;margin:16px 0 20px}
.footer-contact-block{display:flex;flex-direction:column;gap:10px;margin-bottom:20px}
.footer-contact-row{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--gray-400);transition:color 200ms}
.footer-contact-row:hover{color:#fff}
.footer-contact-row i{width:14px;height:14px;color:var(--indigo-xl);flex-shrink:0}
.footer-address-row{display:flex;gap:8px;font-size:13px;line-height:1.55;color:var(--gray-400);margin:4px 0 0}
.footer-address-row i{width:14px;height:14px;color:var(--indigo-xl);flex-shrink:0;margin-top:3px}
.footer-social{display:flex;gap:10px;margin-bottom:20px}
.social-icon{width:38px;height:38px;border-radius:50%;border:1px solid var(--navy-4);background:var(--navy-3);display:flex;align-items:center;justify-content:center;color:var(--gray-400);transition:all 200ms}
.social-icon svg{width:17px;height:17px}
.social-icon:hover{background:var(--indigo);border-color:var(--indigo);color:#fff}
.footer-wa-btn{display:inline-flex;align-items:center;gap:8px;background:#25D366;color:#fff;font-size:13px;font-weight:600;padding:10px 16px;border-radius:var(--radius-sm);font-family:var(--font-head)}
.footer-wa-btn i{width:16px;height:16px}
.footer-wa-btn:hover{background:#1DB954;transform:translateY(-1px)}
.footer-heading{font-size:13px;font-weight:600;color:#fff;margin-bottom:20px;font-family:var(--font-head)}
.footer-links{display:flex;flex-direction:column;gap:2px}
.footer-links a{font-size:14px;color:var(--gray-400);padding:5px 0;transition:color 150ms;display:block}
.footer-links a:hover{color:#fff}
.footer-see-all{color:var(--indigo-xl)!important;font-weight:500}
.footer-bottom{border-top:1px solid var(--navy-4);padding:24px 0;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:16px;font-size:13px;color:var(--gray-400)}
.footer-trust{display:flex;gap:8px;flex-wrap:wrap}
.trust-pill{padding:4px 10px;border:1px solid var(--navy-4);border-radius:var(--radius-pill);font-size:11px;color:var(--gray-400)}
@media(max-width:1023px){.footer-grid{grid-template-columns:1fr 1fr;gap:32px}}
@media(max-width:640px){.footer-grid{grid-template-columns:1fr;gap:24px}.footer-bottom{flex-direction:column;text-align:center}}

/* ========== FLOATING ========== */
.wa-float{position:fixed;bottom:24px;right:24px;z-index:900;width:56px;height:56px;border-radius:50%;background:#25D366;color:#fff;display:flex;align-items:center;justify-content:center;box-shadow:0 4px 16px rgba(37,211,102,.4);opacity:0;pointer-events:none;transition:opacity 300ms ease,transform 200ms ease}
.wa-float.visible{opacity:1;pointer-events:auto}
.wa-float:hover{transform:scale(1.08)}
.wa-float i{width:26px;height:26px}

.mobile-sticky-bar{display:none;position:fixed;bottom:0;left:0;right:0;z-index:900;height:60px;background:#fff;border-top:1px solid var(--gray-200);box-shadow:0 -4px 16px rgba(0,0,0,.08)}
.sticky-call,.sticky-enroll{display:flex;align-items:center;justify-content:center;gap:6px;width:50%;height:100%;font-size:15px;font-weight:600;font-family:var(--font-head)}
.sticky-call{color:var(--indigo);border-right:1px solid var(--gray-200)}
.sticky-call i{width:16px;height:16px}
.sticky-enroll{background:var(--indigo);color:#fff}
@media(max-width:768px){.mobile-sticky-bar{display:flex}body{padding-bottom:60px}.wa-float{bottom:80px;right:16px}}

/* Pulse dot */
.pulse-dot{display:inline-block;width:8px;height:8px;border-radius:50%;background:#10B981;box-shadow:0 0 0 0 rgba(16,185,129,.6);animation:pulseGreen 2s infinite}
@keyframes pulseGreen{0%{box-shadow:0 0 0 0 rgba(16,185,129,.6)}70%{box-shadow:0 0 0 10px rgba(16,185,129,0)}100%{box-shadow:0 0 0 0 rgba(16,185,129,0)}}