/* ==========================================================================
   PETROLIGHT LIMITED (Co. No: 16385250)
   Exact High-Fidelity Clone of Stone Bridge London (stonebridgelondonuk.com)
   ========================================================================== */

:root {
  --color-accent: #00e699;          /* Signature vibrant cyan-green from Stone Bridge */
  --color-accent-dark: #00b377;
  --color-bg-dark: #0a1b2e;         /* Deep London navy */
  --color-card-black: #000000;      /* Pure black for form cards */
  --color-white: #ffffff;
  --color-text-dim: rgba(255, 255, 255, 0.75);
  --color-text-navy: #142233;
  --color-border-line: #00e699;
  
  --font-main: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-serif: 'Enriqueta', Georgia, serif;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-main);
  background-color: #ffffff;
  color: #142233;
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

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

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   1. TRANSPARENT HEADER (Exact Stone Bridge Layout)
   ========================================================================== */
.site-header {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  padding: 30px 0 10px;
  background: transparent;
}

.header-inner {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
}

/* Logo on Left */
.brand-logo {
  display: inline-flex;
  flex-direction: column;
  text-decoration: none;
  cursor: pointer;
}

.logo-line1 {
  font-size: 38px;
  font-weight: 800;
  line-height: 0.92;
  color: #ffffff;
  letter-spacing: -0.02em;
}

.logo-line2 {
  font-size: 38px;
  font-weight: 800;
  line-height: 0.92;
  color: #ffffff;
  letter-spacing: -0.02em;
}

.logo-separator {
  width: 32px;
  height: 5px;
  background-color: #ffffff;
  margin: 6px 0 8px 0;
}

.logo-tagline {
  font-family: var(--font-serif);
  font-size: 14px;
  color: #ffffff;
  letter-spacing: 0.05em;
  line-height: 1.4;
}

/* Right Header Block: Call Us + Phone + Underline + Menu Toggle */
.header-right {
  display: flex;
  align-items: flex-start;
  gap: 20px;
}

.call-us-block {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  text-align: right;
}

.call-us-label {
  font-size: 14px;
  color: #ffffff;
  letter-spacing: 0.05em;
  margin-bottom: 2px;
  line-height: 1.4;
}

.call-us-number {
  font-size: 22px;
  font-weight: 800;
  color: var(--color-accent);
  letter-spacing: 0.05em;
  line-height: 1.2;
  transition: opacity 0.2s;
  white-space: nowrap;
}

.call-us-number:hover {
  opacity: 0.85;
}

.call-us-separator {
  width: 32px;
  height: 5px;
  background-color: #ffffff;
  margin-top: 8px;
}

/* Subtle Hamburger Menu for Quick Section Navigation */
.menu-toggle-btn { display: none; 
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 4px;
  padding: 8px 12px;
  color: #ffffff;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  transition: all 0.2s;
  margin-top: 2px;
}

.menu-toggle-btn:hover {
  background: rgba(255, 255, 255, 0.25);
  border-color: #ffffff;
}

/* ==========================================================================
   2. SLIDE-OUT NAVIGATION DRAWER
   ========================================================================== */
.nav-drawer {
  position: fixed;
  inset: 0;
  background: rgba(5, 15, 26, 0.75);
  backdrop-filter: blur(10px);
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.nav-drawer.active {
  opacity: 1;
  visibility: visible;
}

.drawer-panel {
  position: absolute;
  top: 0;
  right: 0;
  width: 360px;
  max-width: 85%;
  height: 100%;
  background: #000000;
  border-left: 2px solid var(--color-accent);
  padding: 40px 30px;
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  color: #ffffff;
}

.nav-drawer.active .drawer-panel {
  transform: translateX(0);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

.drawer-close {
  background: transparent;
  border: none;
  color: #ffffff;
  cursor: pointer;
}

.drawer-nav {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-bottom: 30px;
}

.drawer-nav a {
  font-size: 1.15rem;
  font-weight: 700;
  color: #ffffff;
  padding: 6px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  transition: color 0.2s, padding-left 0.2s;
}

.drawer-nav a:hover {
  color: var(--color-accent);
  padding-left: 8px;
}

.drawer-corporate {
  margin-top: auto;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.6;
}

.drawer-corporate strong {
  color: var(--color-accent);
}

/* ==========================================================================
   3. HERO SECTION (Exact Stone Bridge Layout with Offset White Box)
   ========================================================================== */
.hero-section {
  position: relative;
  min-height: 800px;
  background-color: #0b1a2d !important;
  background-image: 
    linear-gradient(180deg, rgba(14, 44, 80, 0.88) 0%, rgba(11, 35, 65, 0.82) 50%, rgba(8, 26, 48, 0.92) 100%),
    url('../images/hero_bg.jpg');
  background-size: cover;
  background-position: center center;
  color: #ffffff;
  padding-top: 140px;
  padding-bottom: 90px;
  display: flex;
  align-items: center;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.95fr;
  gap: 70px;
  align-items: center;
}

/* Left Hero Column */
.hero-left {
  position: relative;
  z-index: 2;
}

.hero-subtitle-green {
  font-size: 18px;
  color: var(--color-accent);
  margin-bottom: 16px;
  font-weight: 600;
}

.hero-big-title {
  font-size: clamp(3rem, 5.2vw, 4.2rem);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.01em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.24);
  margin-bottom: 30px;
  user-select: none;
}

.hero-big-title span {
  display: block;
}

.hero-paragraph {
  font-size: 16px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.8);
  max-width: 500px;
}

/* Right Hero Column: Offset White Frame & Deep Black Card */
.form-box-wrapper {
  position: relative;
  max-width: 480px;
  margin-left: auto;
}

/* The iconic white offset frame */
.form-frame-offset {
  position: absolute;
  top: -30px;
  left: -30px;
  right: 30px;
  bottom: 30px;
  border: 10px solid #ffffff;
  z-index: 1;
  pointer-events: none;
}

.form-black-card {
  position: relative;
  z-index: 2;
  background: #000000;
  padding: 45px 38px 40px;
  color: #ffffff;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
}

.form-title-green {
  font-size: 38px;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 8px;
  letter-spacing: -0.02em;
  line-height: 1.15;
}

.form-desc-white {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 26px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-bottom: 14px;
}

.form-field {
  margin-bottom: 14px;
}

.form-label-green {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: 6px;
}

.stone-input, .stone-textarea {
  width: 100%;
  padding: 10px 14px;
  background: #ffffff;
  color: #000000;
  border: 1px solid #ffffff;
  border-radius: 0;
  font-size: 14px;
  outline: none;
  font-family: var(--font-main);
  transition: box-shadow 0.2s;
}

.stone-input:focus, .stone-textarea:focus {
  box-shadow: 0 0 0 3px rgba(0, 230, 153, 0.4);
}

.stone-textarea {
  height: 95px;
  resize: vertical;
}

.stone-submit-btn {
  width: 100%;
  height: 48px;
  background: var(--color-accent);
  color: #000000;
  border: none;
  border-radius: 0;
  font-size: 15px;
  font-weight: 800;
  cursor: pointer;
  margin-top: 10px;
  transition: all 0.2s;
  letter-spacing: 0.02em;
}

.stone-submit-btn:hover {
  background: #00ffaa;
  transform: translateY(-1px);
}

.feedback-msg {
  display: none;
  padding: 10px 12px;
  margin-top: 14px;
  font-size: 13px;
  background: rgba(0, 230, 153, 0.15);
  border: 1px solid var(--color-accent);
  color: var(--color-accent);
}

/* ==========================================================================
   4. SERVICES SECTION (Exact Circular Layout)
   ========================================================================== */
.services-section {
  background: #e9eef2;
  background-image: 
    linear-gradient(180deg, rgba(235, 240, 245, 0.95) 0%, rgba(230, 236, 242, 0.95) 100%),
    url('../images/hero_bg.jpg');
  background-size: cover;
  background-position: center;
  padding: 110px 0 120px;
  text-align: center;
}

.services-main-title {
  font-size: 56px;
  font-weight: 700;
  color: var(--color-text-navy);
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.services-main-subtitle {
  font-size: 18px;
  line-height: 1.8;
  color: #445566;
  max-width: 720px;
  margin: 0 auto 70px;
}

.services-cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.service-circle-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.service-circle-img-box {
  width: 130px;
  height: 130px;
  border-radius: 50%;
  overflow: hidden;
  margin-bottom: 26px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.service-circle-img-box img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s;
}

.service-circle-item:hover .service-circle-img-box img {
  transform: scale(1.1);
}

.service-item-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-text-navy);
  margin-bottom: 16px;
}

.service-item-text {
  font-size: 15px;
  line-height: 1.8;
  color: #4f6070;
  text-align: center;
}

/* ==========================================================================
   5. TRUSTED PARTNER SECTION (White Crisp Section with 3 Square Icons)
   ========================================================================== */
.partner-section {
  background: #ffffff;
  padding: 110px 0 120px;
  text-align: center;
}

.partner-pre-title {
  font-size: 18px;
  font-weight: 700;
  color: #000000;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 18px;
}

.partner-main-headline {
  font-size: clamp(2.2rem, 3.8vw, 3.4rem);
  font-weight: 800;
  line-height: 1.25;
  color: var(--color-text-navy);
  max-width: 900px;
  margin: 0 auto 80px;
  letter-spacing: -0.02em;
}

.partner-pillars-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  position: relative;
}

/* Green connecting line between boxes */
.partner-connecting-line {
  position: absolute;
  top: 45px;
  left: 20%;
  right: 20%;
  height: 2px;
  background-color: var(--color-accent);
  z-index: 1;
}

.pillar-col {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.pillar-box-icon {
  width: 90px;
  height: 90px;
  background: #000000;
  border: 3px solid var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.pillar-box-icon svg {
  width: 42px;
  height: 42px;
  color: var(--color-accent);
}

.pillar-title {
  font-size: 19px;
  font-weight: 700;
  color: var(--color-text-navy);
  margin-bottom: 12px;
}

.pillar-desc {
  font-size: 15px;
  line-height: 1.7;
  color: #667788;
  max-width: 300px;
}

/* ==========================================================================
   6. CAMDEN PROJECT BANNER SECTION
   ========================================================================== */
.banner-section {
  width: 100%;
  position: relative;
  overflow: hidden;
  background-color: #101e2e;
}

.banner-img {
  width: 100%;
  height: auto;
  max-height: 640px;
  object-fit: cover;
  display: block;
}

/* ==========================================================================
   7. ABOUT US & CONTACT US SECTION (Bottom Dark Blue Section)
   ========================================================================== */
.bottom-section {
  background-color: #0b1a2d !important;
  background-image: 
    linear-gradient(180deg, rgba(12, 38, 70, 0.94) 0%, rgba(9, 28, 52, 0.96) 100%),
    url('../images/hero_bg.jpg');
  background-size: cover;
  background-position: center bottom;
  color: #ffffff;
  padding: 120px 0 130px;
}

.bottom-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.95fr;
  gap: 70px;
  align-items: flex-start;
}

/* About Us Left */
.about-left-col {
  padding-right: 20px;
}

.about-more-info {
  font-size: 14px;
  color: var(--color-accent);
  margin-bottom: 14px;
  font-weight: 600;
}

.about-main-title {
  font-size: 38px;
  font-weight: 800;
  line-height: 1.15;
  color: var(--color-accent);
  letter-spacing: 0.05em;
  margin-bottom: 28px;
  text-transform: uppercase;
}

.about-main-title span {
  display: block;
}

.about-body-p {
  font-size: 15px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 22px;
}

/* Official UK Company Info Card */
.corporate-official-box {
  margin-top: 36px;
  background: rgba(0, 0, 0, 0.5);
  border: 1px solid var(--color-accent);
  padding: 24px;
}

.corporate-official-box h4 {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--color-accent);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.corporate-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.corporate-table td {
  padding: 6px 0;
  vertical-align: top;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.corporate-table td.label {
  color: rgba(255, 255, 255, 0.6);
  width: 38%;
}

.corporate-table td.val {
  color: #ffffff;
  font-weight: 600;
}

.corporate-table td.val strong {
  color: var(--color-accent);
}

/* Contact Us Right (Offset White Box Behind Black Card) */
.contact-frame-wrapper {
  position: relative;
  max-width: 480px;
  margin-left: auto;
}

/* Shifted down and right */
.contact-frame-offset {
  position: absolute;
  top: 30px;
  left: 30px;
  right: -30px;
  bottom: -30px;
  border: 10px solid #ffffff;
  z-index: 1;
  pointer-events: none;
}

.contact-black-card {
  position: relative;
  z-index: 2;
  background: #000000;
  padding: 45px 38px 40px;
  color: #ffffff;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
}

.contact-headline-green {
  font-size: 38px;
  font-weight: 800;
  color: var(--color-accent);
  letter-spacing: 1.9px;
  margin-bottom: 24px;
  text-transform: uppercase;
}

/* ==========================================================================
   8. MINIMAL FOOTER BAR
   ========================================================================== */
.site-footer-bar {
  background: #050e18;
  padding: 24px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-inner a:hover {
  color: var(--color-accent);
}

/* ==========================================================================
   9. RESPONSIVE BREAKPOINTS
   ========================================================================== */
@media (max-width: 992px) {
  .hero-grid, .bottom-grid {
    grid-template-columns: 1fr;
    gap: 60px;
  }
  
  .form-box-wrapper, .contact-frame-wrapper {
    margin: 0 auto;
    max-width: 500px;
  }

  .services-cards-grid {
    grid-template-columns: 1fr;
    gap: 50px;
    max-width: 480px;
    margin: 0 auto;
  }

  .partner-pillars-row {
    grid-template-columns: 1fr;
    gap: 50px;
  }

  .partner-connecting-line {
    display: none;
  }
  
  .banner-section {
    height: auto;
    padding: 60px 0;
  }

  .banner-content {
    margin-left: 0;
    max-width: 100%;
  }
  
  .banner-pill {
    font-size: 20px;
  }
  
  .banner-card-box p, .banner-enquire {
    font-size: 18px;
  }
}

@media (max-width: 640px) {
  .site-header {
    padding: 20px 0;
  }

  .logo-line1, .logo-line2 {
    font-size: 28px;
  }

  .call-us-number {
    font-size: 16px;
  }

  .form-frame-offset {
    top: -15px;
    left: -15px;
    right: 15px;
    bottom: 15px;
    border-width: 6px;
  }

  .contact-frame-offset {
    top: 15px;
    left: 15px;
    right: -15px;
    bottom: -15px;
    border-width: 6px;
  }

  .form-black-card, .contact-black-card {
    padding: 30px 20px;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .services-main-title {
    font-size: 38px;
  }

  .partner-main-headline {
    font-size: 28px;
  }
}