/* ═══════════════════════════════════════════════════════════
   CASE STUDY 03 — CORPORATE & INSTITUTIONAL DOCUMENTARIES
   Theme: Pristine, Deep Corporate Blue, Minimal Slate, Professional
   ═══════════════════════════════════════════════════════════ */

:root {
  --cs3-bg-primary: #0a0f18; /* Deep corporate slate blue */
  --cs3-bg-secondary: #111827; /* Lighter slate */
  --cs3-bg-tertiary: #1f2937; /* Card background */
  
  --cs3-text-primary: #f9fafb;
  --cs3-text-secondary: #d1d5db;
  --cs3-text-dim: #9ca3af;
  
  --cs3-accent-1: #3b82f6; /* Professional royal blue */
  --cs3-accent-2: #10b981; /* Emerald green */
  --cs3-accent-3: #f59e0b; /* Amber gold */
  
  --cs3-accent-glow: rgba(59, 130, 246, 0.4);
  
  --cs3-border: rgba(255, 255, 255, 0.08);
  --cs3-radius: 6px; /* Sharper, cleaner borders for corporate feel */
  --cs3-radius-lg: 12px;
  
  --cs3-font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --cs3-font-heading: 'Outfit', 'Inter', sans-serif;
}

/* ─── Base Reset & Smooth Scroll ─── */
html {
  scroll-behavior: smooth;
}

body.cs3-body {
  margin: 0;
  padding: 0;
  background-color: var(--cs3-bg-primary);
  color: var(--cs3-text-primary);
  font-family: var(--cs3-font-sans);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ─── Background Ambient Elements ─── */
.cs3-bg-element {
  position: fixed;
  border-radius: 50%;
  filter: blur(120px);
  z-index: -1;
  opacity: 0.3;
  pointer-events: none;
}
.cs3-bg-glow-1 {
  width: 60vw;
  height: 60vw;
  background: radial-gradient(circle, var(--cs3-accent-glow) 0%, transparent 70%);
  top: -20vh;
  right: -10vw;
}
.cs3-bg-glow-2 {
  width: 50vw;
  height: 50vw;
  background: radial-gradient(circle, rgba(29, 78, 216, 0.2) 0%, transparent 70%);
  bottom: -10vh;
  left: -10vw;
}

/* ─── Navigation & Back Button ─── */
.cs3-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 24px 5%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 100;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(10, 15, 24, 0.8);
  border-bottom: 1px solid var(--cs3-border);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  box-sizing: border-box;
}

.cs3-nav.hidden {
  transform: translateY(-100%);
}

.cs3-back-btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--cs3-text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: all 0.3s ease;
}

.cs3-back-btn svg {
  width: 20px;
  height: 20px;
  transition: transform 0.3s ease;
}

.cs3-back-btn:hover {
  color: var(--cs3-text-primary);
}
.cs3-back-btn:hover svg {
  transform: translateX(-4px);
}

.cs3-nav-label {
  font-family: var(--cs3-font-heading);
  font-weight: 600;
  letter-spacing: 0.1em;
  font-size: 0.85rem;
  color: var(--cs3-accent);
  text-transform: uppercase;
}

/* ─── Layout Containers ─── */
.cs3-container {
  max-width: 900px; /* Reduced to enforce single column feel */
  margin: 0 auto;
  padding: 0 5%;
}
.cs3-container-narrow {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 5%;
}

/* ─── Hero Section ─── */
.cs3-hero {
  padding: 180px 0 80px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}

.cs3-eyebrow-wrap {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 24px;
}
.cs3-eyebrow {
  font-family: var(--cs3-font-heading);
  font-weight: 600;
  letter-spacing: 0.15em;
  font-size: 0.85rem;
  color: var(--cs3-text-dim);
  text-transform: uppercase;
}
.cs3-eyebrow-badge {
  background: rgba(59, 130, 246, 0.1);
  color: var(--cs3-accent);
  border: 1px solid rgba(59, 130, 246, 0.2);
  padding: 4px 12px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.cs3-hero-title {
  font-family: var(--cs3-font-heading);
  font-size: clamp(36px, 5vw, 64px);
  line-height: 1.15;
  font-weight: 500;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #ffffff 0%, var(--cs3-accent-3) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  color: transparent;
  margin-bottom: 30px;
  max-width: 1000px;
}

/* ─── Video Layout Placeholder ─── */
.cs3-video-grid {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3rem;
  width: 100%;
  margin: 40px auto 0;
  max-width: 900px;
}

.cs3-video-placeholder {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--cs3-bg-secondary);
  border: 1px solid var(--cs3-border);
  border-radius: var(--cs3-radius);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  max-width: 800px;
}

.cs3-video-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    45deg,
    transparent,
    transparent 10px,
    rgba(255, 255, 255, 0.02) 10px,
    rgba(255, 255, 255, 0.02) 20px
  );
  opacity: 0.5;
}

.cs3-video-play-icon {
  width: 64px;
  height: 64px;
  background: var(--cs3-bg-tertiary);
  border: 1px solid var(--cs3-border);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--cs3-text-secondary);
  z-index: 2;
  transition: all 0.3s ease;
}
.cs3-video-play-icon svg {
  width: 24px;
  height: 24px;
  margin-left: 4px;
}

.cs3-video-label {
  margin-top: 16px;
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--cs3-text-dim);
  text-transform: uppercase;
  z-index: 2;
}

/* ─── General Section Styling ─── */
.cs3-section {
  padding: 80px 0;
}

.cs3-section-header {
  margin-bottom: 40px;
  position: relative;
}

.cs3-meta-label {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  color: var(--cs3-accent);
  text-transform: uppercase;
  margin-bottom: 16px;
  display: block;
}

.cs3-section-rule {
  border: none;
  height: 1px;
  background: var(--cs3-border);
  margin: 0 0 32px 0;
}

.cs3-section-heading {
  font-family: var(--cs3-font-heading);
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.2;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--cs3-text-primary);
  margin-bottom: 0;
  position: relative;
  z-index: 2;
}

/* ─── Motion Graphics Elements ─── */
.cs3-mg-element {
  position: absolute;
  opacity: 0.15;
  pointer-events: none;
  z-index: 1;
}

.mg-spin {
  animation: mgSpin 12s linear infinite;
}
.mg-pulse {
  animation: mgPulse 4s ease-in-out infinite;
}
.mg-float {
  animation: mgFloat 6s ease-in-out infinite;
}

@keyframes mgSpin {
  100% { transform: rotate(360deg); }
}
@keyframes mgPulse {
  0%, 100% { transform: scale(1); opacity: 0.15; }
  50% { transform: scale(1.1); opacity: 0.3; }
}
@keyframes mgFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* ─── Typography & Paragraphs ─── */
p.cs3-body-text, 
p.cs3-overview-text {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--cs3-text-secondary);
  margin-bottom: 24px;
}

/* ─── Layout Cards (The Strategy) ─── */
.cs3-card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  margin-top: 40px;
}

.cs3-strategy-card {
  background: var(--cs3-bg-secondary);
  border: 1px solid var(--cs3-border);
  border-radius: var(--cs3-radius);
  padding: 40px;
  transition: transform 0.4s ease, border-color 0.4s ease;
}

.cs3-strategy-card:hover {
  transform: translateY(-5px);
  border-color: rgba(59, 130, 246, 0.4);
}

.cs3-card-num {
  font-family: var(--cs3-font-heading);
  font-size: 2.5rem;
  font-weight: 300;
  color: var(--cs3-text-dim);
  opacity: 0.5;
  margin-bottom: 24px;
  display: block;
}

.cs3-card-title {
  font-family: var(--cs3-font-heading);
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--cs3-text-primary);
  margin-bottom: 16px;
  line-height: 1.4;
}

.cs3-card-desc {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--cs3-text-dim);
  margin: 0;
}

/* ─── Profile List Styles ─── */
.cs3-profile-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.cs3-profile-item {
  background: var(--cs3-bg-secondary);
  border-left: 4px solid var(--cs3-accent-1);
  padding: 32px;
  border-radius: 0 var(--cs3-radius) var(--cs3-radius) 0;
}
.cs3-profile-item:nth-child(2) {
  border-left-color: var(--cs3-accent-2);
}
.cs3-profile-item:nth-child(3) {
  border-left-color: var(--cs3-accent-3);
}

.cs3-profile-title {
  font-family: var(--cs3-font-heading);
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--cs3-text-primary);
  margin-bottom: 12px;
}

.cs3-profile-desc {
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--cs3-text-secondary);
  margin: 0;
}

/* ─── Footer ─── */
.cs3-footer {
  text-align: center;
  padding: 80px 0;
  border-top: 1px solid var(--cs3-border);
  margin-top: 60px;
}

.cs3-footer-content {
  max-width: 800px;
  margin: 0 auto;
}

/* ─── Animations & Utility ─── */
.fade-slide-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 1s cubic-bezier(0.16, 1, 0.3, 1), transform 1s cubic-bezier(0.16, 1, 0.3, 1);
}
.fade-slide-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Text Mask Reveal (Word by Word) */
.text-mask-reveal .word {
  display: inline-block;
  overflow: hidden;
  vertical-align: bottom;
  margin-right: 0.25em; /* spacing between words */
}

.text-mask-reveal .word-inner {
  display: inline-block;
  transform: translateY(110%);
  transition: transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
  background: linear-gradient(180deg, #ffffff 40%, var(--cs3-text-dim) 100%) !important;
  -webkit-background-clip: text !important;
  -webkit-text-fill-color: transparent !important;
  background-clip: text !important;
  color: transparent !important;
}

.text-mask-reveal.visible .word-inner {
  transform: translateY(0);
}