/* ===== DEREK ENGINEERING GROUP — WHITE & SKY BLUE THEME ===== */
:root {
  --sky:        #0EA5E9;
  --sky-dark:   #0369A1;
  --sky-mid:    #38BDF8;
  --sky-light:  #BAE6FD;
  --sky-pale:   #F0F9FF;
  --white:      #FFFFFF;
  --off-white:  #F8FAFC;
  --charcoal:   #1E293B;
  --steel:      #475569;
  --silver:     #94A3B8;
  --grad-sky:   linear-gradient(135deg, #0EA5E9 0%, #38BDF8 50%, #0EA5E9 100%);
  --grad-dark:  linear-gradient(135deg, #0369A1 0%, #0EA5E9 100%);
  --shadow-lg:  0 20px 60px rgba(14,165,233,0.18);
  --shadow-sky: 0 8px 32px rgba(14,165,233,0.25);
  --radius:     12px;
  --transition: all 0.4s cubic-bezier(0.25,0.46,0.45,0.94);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: 'Inter', sans-serif; color: var(--charcoal); background: var(--white); overflow-x: hidden; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; display: block; }
section { position: relative; }

/* ===== TYPOGRAPHY ===== */
.display-heading { font-family: 'Playfair Display', serif; font-weight: 700; line-height: 1.15; }
.section-label {
  font-family: 'Rajdhani', sans-serif; font-size: 0.78rem; font-weight: 600;
  letter-spacing: 3px; text-transform: uppercase; color: var(--sky);
}
.section-title { font-family: 'Playfair Display', serif; font-weight: 700; color: var(--charcoal); line-height: 1.2; }
.sky-text { color: var(--sky); }
.white-text { color: var(--white); }

/* ===== UTILITY ===== */
.container-xl { max-width: 1320px; margin: 0 auto; padding: 0 24px; }
.section-pad { padding: 100px 0; }
.section-pad-sm { padding: 60px 0; }
.divider-sky { width: 60px; height: 3px; background: var(--grad-sky); border-radius: 2px; margin: 16px 0 32px; }
.divider-sky.center { margin: 16px auto 32px; }

/* ===== BUTTONS ===== */
.btn-primary {
  display: inline-flex; align-items: center; gap: 10px;
  background: var(--grad-sky); color: var(--white);
  font-family: 'Rajdhani', sans-serif; font-weight: 700; font-size: 0.95rem;
  letter-spacing: 1.5px; text-transform: uppercase; padding: 16px 36px;
  border-radius: 4px; border: none; cursor: pointer; transition: var(--transition);
  box-shadow: var(--shadow-sky);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 40px rgba(14,165,233,0.4); }
.btn-outline {
  display: inline-flex; align-items: center; gap: 10px;
  background: transparent; color: var(--sky);
  font-family: 'Rajdhani', sans-serif; font-weight: 700; font-size: 0.95rem;
  letter-spacing: 1.5px; text-transform: uppercase; padding: 14px 34px;
  border-radius: 4px; border: 2px solid var(--sky); cursor: pointer; transition: var(--transition);
}
.btn-outline:hover { background: var(--sky); color: var(--white); }
.btn-dark {
  display: inline-flex; align-items: center; gap: 10px;
  background: var(--charcoal); color: var(--white);
  font-family: 'Rajdhani', sans-serif; font-weight: 700; font-size: 0.9rem;
  letter-spacing: 1.5px; text-transform: uppercase; padding: 14px 32px;
  border-radius: 4px; border: 2px solid var(--charcoal); cursor: pointer; transition: var(--transition);
}
.btn-dark:hover { background: var(--sky-dark); border-color: var(--sky-dark); }

/* ===== NAVIGATION ===== */
#main-nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 9999;
  background: rgba(255,255,255,0.95); backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(14,165,233,0.12);
  transition: var(--transition);
}
#main-nav.scrolled { box-shadow: 0 4px 30px rgba(14,165,233,0.15); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; max-width: 1320px; margin: 0 auto; padding: 14px 24px; }
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-logo-img { height: 48px; width: auto; object-fit: contain; }
.nav-logo-text { line-height: 1.1; }
.nav-logo-text strong { display: block; font-family: 'Playfair Display', serif; font-size: 1.05rem; font-weight: 700; color: var(--charcoal); }
.nav-logo-text span { font-size: 0.68rem; color: var(--sky); letter-spacing: 2px; text-transform: uppercase; font-family: 'Rajdhani', sans-serif; }
.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; }
.nav-links a {
  font-family: 'Rajdhani', sans-serif; font-size: 0.88rem; font-weight: 600;
  letter-spacing: 1.2px; text-transform: uppercase; color: var(--steel);
  padding: 8px 14px; border-radius: 4px; transition: var(--transition);
  display: flex; align-items: center; gap: 6px;
}
.nav-links a:hover, .nav-links a.active { color: var(--sky); }
.nav-links .nav-cta a { background: var(--grad-sky); color: var(--white); padding: 10px 22px; border-radius: 4px; }
.nav-links .nav-cta a:hover { opacity: 0.9; transform: translateY(-1px); }
.nav-hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; }
.nav-hamburger span { width: 26px; height: 2px; background: var(--charcoal); border-radius: 2px; transition: var(--transition); }

/* ===== MOBILE MENU ===== */
.mobile-menu {
  display: none; position: fixed; top: 0; left: 0; right: 0; bottom: 0;
  background: var(--white); z-index: 9998;
  flex-direction: column; align-items: center; justify-content: center; gap: 28px;
  opacity: 0; pointer-events: none; transition: opacity 0.3s;
}
.mobile-menu.open { opacity: 1; pointer-events: all; display: flex; }
.mobile-menu a { font-family: 'Playfair Display', serif; font-size: 2rem; color: var(--charcoal); transition: var(--transition); }
.mobile-menu a:hover { color: var(--sky); }
.mobile-close { position: absolute; top: 28px; right: 28px; font-size: 2rem; color: var(--sky); cursor: pointer; }

/* ===== PAGE HERO (inner pages) ===== */
.page-hero {
  min-height: 380px; padding: 160px 0 80px;
  background: linear-gradient(135deg, var(--sky-dark) 0%, var(--sky) 60%, var(--sky-mid) 100%);
  position: relative; overflow: hidden;
}
.page-hero::before {
  content: ''; position: absolute; inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}
.page-hero-content { position: relative; z-index: 2; text-align: center; }
.page-hero-label { font-family: 'Rajdhani', sans-serif; font-size: 0.78rem; font-weight: 600; letter-spacing: 3px; text-transform: uppercase; color: rgba(255,255,255,0.7); margin-bottom: 16px; }
.page-hero h1 { font-family: 'Playfair Display', serif; font-size: clamp(2.4rem, 5vw, 3.6rem); font-weight: 900; color: var(--white); margin-bottom: 20px; }
.page-hero p { color: rgba(255,255,255,0.8); font-size: 1.05rem; max-width: 600px; margin: 0 auto; line-height: 1.7; }
.breadcrumb { display: flex; align-items: center; justify-content: center; gap: 8px; margin-top: 24px; font-size: 0.82rem; color: rgba(255,255,255,0.6); font-family: 'Rajdhani', sans-serif; }
.breadcrumb a { color: rgba(255,255,255,0.8); transition: var(--transition); }
.breadcrumb a:hover { color: var(--white); }
.breadcrumb i { font-size: 0.6rem; }

/* ===== FORMS ===== */
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 0.8rem; font-weight: 600; letter-spacing: 1px; text-transform: uppercase; color: var(--steel); margin-bottom: 8px; font-family: 'Rajdhani', sans-serif; }
.form-control { width: 100%; padding: 13px 16px; border: 1.5px solid rgba(14,165,233,0.2); border-radius: 8px; font-family: 'Inter', sans-serif; font-size: 0.9rem; color: var(--charcoal); transition: var(--transition); background: var(--white); }
.form-control:focus { outline: none; border-color: var(--sky); box-shadow: 0 0 0 3px rgba(14,165,233,0.12); }
.form-select { width: 100%; padding: 13px 16px; border: 1.5px solid rgba(14,165,233,0.2); border-radius: 8px; font-family: 'Inter', sans-serif; font-size: 0.9rem; color: var(--charcoal); background: var(--white); cursor: pointer; appearance: none; transition: var(--transition); }
.form-select:focus { outline: none; border-color: var(--sky); box-shadow: 0 0 0 3px rgba(14,165,233,0.12); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* ===== CARDS ===== */
.card-base { background: var(--white); border-radius: var(--radius); border: 1px solid rgba(14,165,233,0.1); box-shadow: 0 2px 16px rgba(14,165,233,0.06); transition: var(--transition); }
.card-base:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }

/* ===== STATS BAR ===== */
.stats-bar { background: var(--sky-dark); padding: 48px 0; }
.stats-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 0; }
.stat-item { text-align: center; padding: 20px; position: relative; }
.stat-item:not(:last-child)::after { content: ''; position: absolute; right: 0; top: 20%; bottom: 20%; width: 1px; background: rgba(255,255,255,0.2); }
.stat-number { font-family: 'Playfair Display', serif; font-size: 3rem; font-weight: 900; color: var(--white); line-height: 1; }
.stat-suffix { font-size: 1.8rem; }
.stat-label { font-family: 'Rajdhani', sans-serif; font-size: 0.82rem; letter-spacing: 2px; text-transform: uppercase; color: rgba(255,255,255,0.7); margin-top: 8px; }

/* ===== FOOTER ===== */
footer { background: var(--charcoal); padding: 64px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px; margin-bottom: 56px; }
.footer-brand p { color: rgba(255,255,255,0.5); font-size: 0.88rem; line-height: 1.7; margin: 16px 0 24px; }
.footer-logo-img { height: 44px; width: auto; object-fit: contain; filter: brightness(0) invert(1); margin-bottom: 16px; }
.footer-col h5 { font-family: 'Rajdhani', sans-serif; font-size: 0.82rem; font-weight: 700; letter-spacing: 2px; text-transform: uppercase; color: var(--sky-mid); margin-bottom: 18px; }
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-col ul a { color: rgba(255,255,255,0.5); font-size: 0.87rem; transition: var(--transition); }
.footer-col ul a:hover { color: var(--sky-mid); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding-top: 28px; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; }
.footer-bottom p { font-size: 0.8rem; color: rgba(255,255,255,0.35); }
.footer-bottom a { color: var(--sky-mid); }

/* ===== SOCIAL ICONS ===== */
.social-icons { display: flex; gap: 12px; }
.social-icon { width: 40px; height: 40px; border-radius: 8px; border: 1px solid rgba(255,255,255,0.15); display: flex; align-items: center; justify-content: center; color: rgba(255,255,255,0.5); font-size: 0.95rem; transition: var(--transition); cursor: pointer; }
.social-icon:hover { background: var(--sky); border-color: var(--sky); color: var(--white); }

/* ===== FLOATING BUTTONS ===== */
#float-actions { position: fixed; bottom: 32px; right: 28px; display: flex; flex-direction: column; gap: 12px; z-index: 9997; }
.float-btn { width: 56px; height: 56px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 1.3rem; cursor: pointer; transition: var(--transition); box-shadow: 0 6px 24px rgba(0,0,0,0.2); border: none; text-decoration: none; }
.float-btn:hover { transform: scale(1.1) translateY(-2px); }
.float-btn.whatsapp { background: #25D366; color: #fff; }
.float-btn.whatsapp::after { content: ''; position: absolute; width: 56px; height: 56px; border-radius: 50%; background: rgba(37,211,102,0.4); animation: pulse-wa 2s infinite; }
@keyframes pulse-wa { 0%{transform:scale(1);opacity:0.7} 100%{transform:scale(2);opacity:0} }
.float-btn.chat-toggle { background: var(--sky); color: var(--white); }
.float-btn.back-top { background: rgba(30,41,59,0.85); color: var(--sky-mid); font-size: 1rem; }

/* ===== CHATBOT ===== */
#chatbot { position: fixed; bottom: 110px; right: 28px; width: 360px; background: var(--white); border-radius: 20px; box-shadow: 0 20px 60px rgba(14,165,233,0.2); z-index: 9996; overflow: hidden; transform: scale(0.8) translateY(20px); opacity: 0; pointer-events: none; transition: all 0.35s cubic-bezier(0.34,1.56,0.64,1); transform-origin: bottom right; }
#chatbot.open { transform: scale(1) translateY(0); opacity: 1; pointer-events: all; }
.chatbot-header { background: var(--grad-dark); padding: 18px 20px; display: flex; align-items: center; gap: 12px; }
.chatbot-avatar { width: 38px; height: 38px; border-radius: 50%; background: rgba(255,255,255,0.2); display: flex; align-items: center; justify-content: center; font-size: 1rem; color: var(--white); }
.chatbot-header-info strong { display: block; color: var(--white); font-size: 0.9rem; }
.chatbot-header-info span { font-size: 0.72rem; color: rgba(255,255,255,0.65); }
.chatbot-online-dot { width: 8px; height: 8px; background: #22C55E; border-radius: 50%; margin-left: auto; animation: blink 1.5s infinite; }
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.3} }
.chatbot-close { margin-left: 8px; color: rgba(255,255,255,0.5); cursor: pointer; transition: var(--transition); background: none; border: none; font-size: 1rem; }
.chatbot-close:hover { color: var(--white); }
.chatbot-messages { height: 280px; overflow-y: auto; padding: 20px; display: flex; flex-direction: column; gap: 14px; background: var(--sky-pale); }
.chat-msg { max-width: 82%; padding: 11px 15px; border-radius: 14px; font-size: 0.85rem; line-height: 1.5; }
.chat-msg.bot { background: var(--white); color: var(--charcoal); border-bottom-left-radius: 4px; box-shadow: 0 2px 8px rgba(0,0,0,0.06); align-self: flex-start; }
.chat-msg.user { background: var(--sky); color: var(--white); border-bottom-right-radius: 4px; align-self: flex-end; }
.chat-quick-replies { display: flex; flex-wrap: wrap; gap: 6px; padding: 0 20px 12px; background: var(--sky-pale); }
.quick-reply { font-size: 0.75rem; padding: 6px 14px; border-radius: 20px; border: 1px solid rgba(14,165,233,0.25); color: var(--sky-dark); cursor: pointer; transition: var(--transition); background: var(--white); }
.quick-reply:hover { background: var(--sky); color: var(--white); border-color: var(--sky); }
.chatbot-input-area { display: flex; gap: 10px; padding: 14px 16px; border-top: 1px solid rgba(14,165,233,0.1); background: var(--white); }
.chatbot-input { flex: 1; border: 1.5px solid rgba(14,165,233,0.2); border-radius: 24px; padding: 10px 16px; font-size: 0.85rem; outline: none; transition: var(--transition); font-family: 'Inter', sans-serif; }
.chatbot-input:focus { border-color: var(--sky); }
.chatbot-send { width: 40px; height: 40px; background: var(--sky); border: none; border-radius: 50%; color: var(--white); cursor: pointer; display: flex; align-items: center; justify-content: center; transition: var(--transition); flex-shrink: 0; }
.chatbot-send:hover { background: var(--sky-dark); }

/* ===== ANIMATIONS ===== */
@keyframes fadeInUp { from{opacity:0;transform:translateY(30px)} to{opacity:1;transform:translateY(0)} }
@keyframes bounce { 0%,100%{transform:translateX(-50%) translateY(0)} 50%{transform:translateX(-50%) translateY(8px)} }

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .stats-grid { grid-template-columns: repeat(2,1fr); }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-hamburger { display: flex; }
  .section-pad { padding: 64px 0; }
  .footer-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  #chatbot { width: calc(100vw - 40px); right: 20px; }
  .form-row { grid-template-columns: 1fr; }
}