/* ==========================================================================
   2.5D INTERACTIVE BUSINESS CARD & PORTFOLIO STYLESHEET
   Pure Vanilla CSS - Modern Dark Luxury Glassmorphism
   ========================================================================== */

:root {
  /* Color Tokens */
  --bg-deep: #07090e;
  --bg-surface: #0e121d;
  --bg-card: #141a29;
  --bg-card-hover: #1c2438;
  --bg-glass: rgba(18, 24, 38, 0.72);
  --bg-glass-card: rgba(22, 30, 48, 0.85);

  --accent-indigo: #6366f1;
  --accent-cyan: #06b6d4;
  --accent-violet: #8b5cf6;
  --accent-amber: #f59e0b;
  --accent-emerald: #10b981;
  --accent-pink: #ec4899;

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(99, 102, 241, 0.35);
  --border-cyan-glow: rgba(6, 182, 212, 0.35);

  --text-main: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --font-sans: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Outfit', sans-serif;
  --font-mono: 'Space Grotesk', monospace;

  --card-w: 520px;
  --card-h: 310px;
  --card-radius: 20px;
  --card-thickness: 6px;
}

/* Reset & Box Sizing */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  background-color: var(--bg-deep);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
}

body {
  min-height: 100vh;
  position: relative;
  background-color: var(--bg-deep);
  color: var(--text-main);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* Ambient Lighting Background */
.ambient-lights {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.light-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
}

.orb-indigo {
  width: 500px;
  height: 500px;
  top: -100px;
  left: 15%;
  background: radial-gradient(circle, var(--accent-indigo) 0%, transparent 70%);
}

.orb-cyan {
  width: 450px;
  height: 450px;
  top: 30%;
  right: -80px;
  background: radial-gradient(circle, var(--accent-cyan) 0%, transparent 70%);
}

.orb-amber {
  width: 400px;
  height: 400px;
  bottom: 10%;
  left: 5%;
  background: radial-gradient(circle, #4338ca 0%, transparent 70%);
  opacity: 0.25;
}

/* Top Progress Bar */
.top-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--accent-indigo), var(--accent-cyan), var(--accent-amber));
  z-index: 9999;
  transition: width 0.1s ease-out;
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.7);
}

/* ==========================================================================
   1. 2.5D CARD STAGE & SCROLL TRACK
   ========================================================================== */

.card-scroll-track {
  height: 320vh; /* Gives ample scroll travel for 3 distinct phases */
  position: relative;
  width: 100%;
}

.sticky-viewport {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  perspective: 1200px;
  perspective-origin: 50% 50%;
  overflow: hidden;
  z-index: 10;
}

/* Perspective Floor Grid */
.perspective-stage {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.grid-ground {
  position: absolute;
  width: 200vw;
  height: 200vh;
  bottom: -40%;
  background-image: 
    linear-gradient(to right, rgba(255, 255, 255, 0.04) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 50px 50px;
  transform: rotateX(75deg);
  transform-origin: center center;
  mask-image: radial-gradient(ellipse at center, rgba(0,0,0,1) 10%, transparent 65%);
  -webkit-mask-image: radial-gradient(ellipse at center, rgba(0,0,0,1) 10%, transparent 65%);
}

.stage-spotlight {
  position: absolute;
  width: 600px;
  height: 400px;
  background: radial-gradient(ellipse, rgba(99, 102, 241, 0.12) 0%, transparent 70%);
  filter: blur(40px);
}

/* Stage Header UI */
.stage-header {
  position: absolute;
  top: 40px;
  text-align: center;
  z-index: 20;
  transition: opacity 0.4s ease, transform 0.4s ease;
  pointer-events: none;
}

.badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(12px);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--accent-cyan);
  margin-bottom: 10px;
}

.pulse-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--accent-cyan);
  box-shadow: 0 0 8px var(--accent-cyan);
  animation: pulse-anim 2s infinite;
}

@keyframes pulse-anim {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
}

.scroll-instruction {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 400;
  letter-spacing: -0.02em;
}

/* ==========================================================================
   3D SCENE & THE 2.5D BUSINESS CARD
   ========================================================================== */

.scene-3d {
  position: relative;
  width: var(--card-w);
  height: var(--card-h);
  transform-style: preserve-3d;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
}

/* Ground Shadow under the card */
.card-ground-shadow {
  position: absolute;
  width: 110%;
  height: 100%;
  background: radial-gradient(ellipse at center, rgba(0, 0, 0, 0.85) 0%, rgba(0, 0, 0, 0.4) 45%, transparent 70%);
  filter: blur(28px);
  transform-origin: center center;
  transform: rotateX(65deg) translateZ(-80px) scale(1.15);
  pointer-events: none;
  transition: opacity 0.3s ease;
  z-index: 2;
}

/* The 3D Card Shell */
.card-3d {
  position: relative;
  width: 100%;
  height: 100%;
  border-radius: var(--card-radius);
  transform-style: preserve-3d;
  cursor: grab;
  user-select: none;
  will-change: transform;
  outline: none;
  /* Initial default resting angle (will be driven smoothly by JS) */
  transform: rotateX(50deg) rotateY(0deg) rotateZ(-20deg) translateZ(0px);
}

.card-3d:active {
  cursor: grabbing;
}

/* 3D Physical Thickness Bevels */
.card-thickness-edge {
  position: absolute;
  background: #192033;
  pointer-events: none;
}

.edge-left {
  width: var(--card-thickness);
  height: 100%;
  left: 0;
  top: 0;
  transform-origin: left center;
  transform: rotateY(-90deg);
  background: linear-gradient(to right, #0d121d, #1e263c);
}

.edge-right {
  width: var(--card-thickness);
  height: 100%;
  right: 0;
  top: 0;
  transform-origin: right center;
  transform: rotateY(90deg);
  background: linear-gradient(to left, #0d121d, #1e263c);
}

.edge-top {
  width: 100%;
  height: var(--card-thickness);
  top: 0;
  left: 0;
  transform-origin: center top;
  transform: rotateX(90deg);
  background: #252e47;
}

.edge-bottom {
  width: 100%;
  height: var(--card-thickness);
  bottom: 0;
  left: 0;
  transform-origin: center bottom;
  transform: rotateX(-90deg);
  background: #111623;
}

/* Card Faces */
.card-face {
  position: absolute;
  inset: 0;
  border-radius: var(--card-radius);
  overflow: hidden;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  box-shadow: 
    0 10px 30px -5px rgba(0, 0, 0, 0.6),
    0 0 0 1px rgba(255, 255, 255, 0.12),
    inset 0 1px 1px rgba(255, 255, 255, 0.25);
  background: linear-gradient(135deg, rgba(26, 33, 53, 0.95) 0%, rgba(12, 16, 26, 0.98) 100%);
}

/* FRONT FACE */
.front-face {
  transform: rotateY(0deg) translateZ(calc(var(--card-thickness) / 2));
  display: flex;
  flex-direction: column;
}

/* BACK FACE */
.back-face {
  transform: rotateY(180deg) translateZ(calc(var(--card-thickness) / 2));
  display: flex;
  flex-direction: column;
  background: linear-gradient(140deg, rgba(19, 25, 42, 0.97) 0%, rgba(9, 12, 20, 0.99) 100%);
}

/* Holographic / Specular Glare */
.foil-glare {
  position: absolute;
  inset: -50%;
  background: linear-gradient(
    115deg,
    transparent 20%,
    rgba(255, 255, 255, 0.08) 35%,
    rgba(6, 182, 212, 0.25) 45%,
    rgba(99, 102, 241, 0.25) 55%,
    transparent 75%
  );
  pointer-events: none;
  mix-blend-mode: overlay;
  z-index: 5;
  transition: transform 0.1s ease-out, opacity 0.2s ease;
}

/* Front Face Internal Layout */
.front-layout {
  position: relative;
  z-index: 2;
  height: 100%;
  padding: 26px 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.card-top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.smart-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 10px;
  background: linear-gradient(135deg, #e2b714 0%, #ca8a04 100%);
  border-radius: 6px;
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.4), 0 2px 5px rgba(0,0,0,0.3);
}

.chip-circuit {
  width: 16px;
  height: 12px;
  border: 1px solid rgba(0,0,0,0.35);
  border-radius: 2px;
  position: relative;
}

.chip-circuit::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  height: 1px;
  background: rgba(0,0,0,0.35);
}

.chip-text {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 800;
  color: #1a1202;
  letter-spacing: 0.05em;
}

.card-monogram {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-secondary);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 4px 8px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.03);
}

.mono-symbol {
  color: var(--accent-cyan);
  font-size: 0.85rem;
}

.card-identity-section {
  margin: auto 0;
}

.role-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--accent-cyan);
  margin-bottom: 6px;
}

.personal-name {
  font-family: var(--font-display);
  font-size: 2.1rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #ffffff;
  margin-bottom: 6px;
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.name-en {
  font-size: 1.1rem;
  font-weight: 400;
  color: var(--text-secondary);
  letter-spacing: 0.04em;
}

.headline-catchphrase {
  font-size: 0.92rem;
  color: #cbd5e1;
  font-weight: 400;
  line-height: 1.45;
}

.card-bottom-bar {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 14px;
}

.hash-keywords {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.kw-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  background: rgba(99, 102, 241, 0.12);
  color: #a5b4fc;
  border: 1px solid rgba(99, 102, 241, 0.25);
  padding: 3px 8px;
  border-radius: 6px;
}

.interactive-prompt {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent-cyan);
  font-weight: 600;
  letter-spacing: 0.05em;
}

.flip-icon-wrapper {
  width: 18px;
  height: 18px;
  animation: rotate-prompt 3s ease-in-out infinite;
}

.flip-svg {
  width: 100%;
  height: 100%;
}

@keyframes rotate-prompt {
  0%, 100% { transform: rotate(0deg); }
  50% { transform: rotate(180deg); }
}

/* Back Face Internal Layout */
.back-layout {
  position: relative;
  z-index: 2;
  height: 100%;
  padding: 24px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.back-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 12px;
}

.back-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--accent-indigo);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.status-indicator {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--accent-emerald);
}

.online-indicator {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
}

.back-quote-box {
  position: relative;
  background: rgba(255, 255, 255, 0.03);
  border-left: 3px solid var(--accent-cyan);
  padding: 12px 16px;
  border-radius: 0 8px 8px 0;
  margin: 10px 0;
}

.quote-mark {
  position: absolute;
  top: -8px;
  left: 6px;
  font-size: 2rem;
  color: rgba(6, 182, 212, 0.15);
  font-family: serif;
  line-height: 1;
}

.quote-content {
  font-size: 0.95rem;
  color: #f1f5f9;
  line-height: 1.45;
  font-weight: 400;
}

.quote-content strong {
  color: var(--accent-cyan);
  font-weight: 600;
}

.quote-author {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.back-summary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 6px 0;
}

.summary-col {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 8px;
  padding: 10px;
}

.col-num {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--accent-indigo);
  font-weight: 700;
}

.summary-col h4 {
  font-size: 0.8rem;
  font-weight: 600;
  color: #f8fafc;
  margin: 2px 0 3px;
}

.summary-col p {
  font-size: 0.68rem;
  color: var(--text-secondary);
  line-height: 1.3;
}

.back-footer {
  display: flex;
  justify-content: center;
  align-items: center;
}

.zoom-cue {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent-cyan);
  letter-spacing: 0.06em;
}

.zoom-glow-bar {
  width: 24px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent-cyan));
}

.zoom-glow-bar:last-child {
  background: linear-gradient(90deg, var(--accent-cyan), transparent);
}

/* Stage HUD Widget */
.stage-hud {
  position: absolute;
  bottom: 30px;
  z-index: 30;
  background: rgba(14, 18, 29, 0.85);
  border: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(16px);
  padding: 8px 18px;
  border-radius: 999px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
}

.hud-phase-track {
  display: flex;
  align-items: center;
  gap: 12px;
}

.hud-step {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  transition: all 0.3s ease;
  white-space: nowrap;
}

.hud-step.active {
  color: var(--accent-cyan);
  font-weight: 700;
  text-shadow: 0 0 10px rgba(6, 182, 212, 0.5);
}

.hud-line {
  width: 20px;
  height: 1px;
  background: rgba(255, 255, 255, 0.15);
}

/* ==========================================================================
   2. FULL WEBSITE DETAILED PORTFOLIO CONTENT
   ========================================================================== */

.portfolio-main {
  position: relative;
  z-index: 20;
  background-color: var(--bg-deep);
  opacity: 1;
  transition: opacity 0.4s ease;
}

/* Sticky Glass Navbar */
.glass-nav {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(9, 12, 20, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: all 0.3s ease;
}

.nav-container {
  max-width: 1180px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-main);
  font-weight: 700;
  font-size: 1.05rem;
  transition: opacity 0.2s ease;
}

.nav-brand:hover {
  opacity: 0.85;
}

.brand-badge {
  background: linear-gradient(135deg, var(--accent-indigo), var(--accent-cyan));
  color: #fff;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 2px 7px;
  border-radius: 6px;
  font-weight: 800;
}

.nav-menu {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 28px;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  transition: color 0.2s ease;
}

.nav-link:hover {
  color: #ffffff;
}

.nav-btn-contact {
  text-decoration: none;
  background: linear-gradient(135deg, var(--accent-indigo) 0%, #4f46e5 100%);
  color: #fff;
  padding: 8px 18px;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 600;
  transition: all 0.25s ease;
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.35);
}

.nav-btn-contact:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

/* Content Sections Layout */
.content-section {
  padding: 100px 24px;
  position: relative;
}

.section-container {
  max-width: 1180px;
  margin: 0 auto;
}

.section-heading {
  margin-bottom: 56px;
}

.section-heading.text-center {
  text-align: center;
}

.section-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--accent-cyan);
  background: rgba(6, 182, 212, 0.08);
  border: 1px solid rgba(6, 182, 212, 0.25);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.section-title {
  font-family: var(--font-display);
  font-size: 2.3rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #ffffff;
  margin-bottom: 14px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto;
}

/* SECTION 1: HERO */
.hero-section {
  padding-top: 80px;
  padding-bottom: 100px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 48px;
  align-items: center;
}

.subhead-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 16px;
}

.sparkle {
  color: var(--accent-amber);
}

.hero-title {
  font-family: var(--font-display);
  font-size: 3rem;
  line-height: 1.25;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
}

.gradient-text {
  background: linear-gradient(135deg, #38bdf8 0%, #818cf8 50%, #c084fc 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-lead {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 32px;
}

.hero-stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 36px;
}

.stat-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.stat-card:hover {
  transform: translateY(-2px);
  border-color: var(--border-glow);
}

.stat-icon {
  font-size: 1.6rem;
}

.stat-info {
  display: flex;
  flex-direction: column;
}

.stat-value {
  font-weight: 700;
  font-size: 0.98rem;
  color: #ffffff;
}

.stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.hero-actions {
  display: flex;
  gap: 16px;
  align-items: center;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: linear-gradient(135deg, var(--accent-indigo) 0%, #4338ca 100%);
  color: #ffffff;
  text-decoration: none;
  padding: 14px 28px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.98rem;
  box-shadow: 0 8px 25px rgba(99, 102, 241, 0.4);
  transition: all 0.25s ease;
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 30px rgba(99, 102, 241, 0.55);
}

.btn-arrow {
  transition: transform 0.2s ease;
}

.btn-primary:hover .btn-arrow {
  transform: translateX(4px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  padding: 14px 24px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--text-main);
  text-decoration: none;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.98rem;
  transition: all 0.2s ease;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.25);
}

/* Hero Code Block Visual */
.glass-quote-container {
  background: rgba(14, 18, 29, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 18px;
  overflow: hidden;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5), 0 0 30px rgba(99, 102, 241, 0.1);
}

.code-card-decor {
  display: flex;
  align-items: center;
  padding: 12px 18px;
  background: rgba(255, 255, 255, 0.03);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  gap: 8px;
}

.decor-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.decor-dot.red { background: #ef4444; }
.decor-dot.yellow { background: #eab308; }
.decor-dot.green { background: #22c55e; }

.decor-title {
  margin-left: 8px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.code-body {
  padding: 24px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.65;
}

.code-comment { color: var(--text-muted); font-style: italic; margin-bottom: 8px; }
.token-keyword { color: var(--accent-pink); font-weight: 600; }
.token-var { color: #38bdf8; }
.token-key { color: #cbd5e1; }
.token-string { color: #a7f3d0; }
.token-bool { color: #f59e0b; }
.indent { padding-left: 20px; }

.code-quote-highlight {
  margin-top: 20px;
  padding: 16px;
  background: rgba(99, 102, 241, 0.12);
  border-left: 3px solid var(--accent-indigo);
  border-radius: 0 8px 8px 0;
  color: #e0e7ff;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  line-height: 1.55;
  font-weight: 500;
}

/* SECTION 2: PHILOSOPHY */
.philosophy-cards-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.philo-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 18px;
  padding: 32px;
  position: relative;
  transition: all 0.3s ease;
  overflow: hidden;
}

.philo-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-glow);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4), 0 0 20px rgba(99, 102, 241, 0.15);
}

.philo-card-wide {
  grid-column: span 2;
}

.philo-icon-box {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.philo-number {
  position: absolute;
  top: 28px;
  right: 28px;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 800;
  color: rgba(255, 255, 255, 0.08);
}

.philo-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 12px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.en-sub {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--accent-cyan);
}

.philo-text {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* SECTION 3: CURRICULUM */
.curriculum-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.curriculum-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 20px;
  padding: 36px;
  position: relative;
  transition: all 0.3s ease;
}

.curriculum-item:hover {
  border-color: var(--border-cyan-glow);
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(0,0,0,0.35);
}

.curr-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 4px 10px;
  border-radius: 6px;
  background: rgba(99, 102, 241, 0.15);
  color: #a5b4fc;
  margin-bottom: 16px;
}

.curr-badge.maker {
  background: rgba(6, 182, 212, 0.15);
  color: #67e8f9;
}

.curr-badge.ethics {
  background: rgba(245, 158, 11, 0.15);
  color: #fcd34d;
}

.curr-badge.project {
  background: rgba(16, 185, 129, 0.15);
  color: #6ee7b7;
}

.curr-icon {
  font-size: 2.2rem;
  margin-bottom: 16px;
}

.curr-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
}

.curr-tool {
  font-size: 0.92rem;
  color: var(--text-main);
  margin-bottom: 4px;
}

.curr-target {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.curr-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 20px;
}

.curr-points {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 16px;
}

.curr-points li {
  font-size: 0.88rem;
  color: #cbd5e1;
  display: flex;
  align-items: center;
  gap: 8px;
}

.curr-points li::before {
  content: '✓';
  color: var(--accent-cyan);
  font-weight: 800;
}

/* SECTION 4: PROJECTS */
.projects-featured-list {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.featured-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 20px;
  padding: 36px;
  transition: all 0.3s ease;
}

.featured-card:hover {
  border-color: var(--border-glow);
  transform: translateX(4px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
}

.project-tag-strip {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.p-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  color: #818cf8;
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.2);
  padding: 3px 8px;
  border-radius: 4px;
}

.p-tag.maker-tag {
  color: #38bdf8;
  background: rgba(6, 182, 212, 0.1);
  border-color: rgba(6, 182, 212, 0.2);
}

.p-tag.ethics-tag {
  color: #fbbf24;
  background: rgba(245, 158, 11, 0.1);
  border-color: rgba(245, 158, 11, 0.2);
}

.project-name {
  font-size: 1.45rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 12px;
}

.project-summary {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
}

.project-takeaway {
  background: rgba(255, 255, 255, 0.03);
  border-left: 3px solid var(--accent-cyan);
  padding: 12px 18px;
  border-radius: 0 8px 8px 0;
  font-size: 0.92rem;
  color: #e2e8f0;
}

.takeaway-label {
  font-weight: 700;
  color: var(--accent-cyan);
  margin-right: 6px;
}

/* SECTION 5: CAREER */
.career-dual-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
}

.career-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 20px;
  padding: 36px;
}

.career-box-title {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 28px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.box-icon {
  font-size: 1.4rem;
}

/* Timeline */
.timeline-list {
  display: flex;
  flex-direction: column;
  gap: 28px;
  position: relative;
  padding-left: 20px;
}

.timeline-list::before {
  content: '';
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: 5px;
  width: 2px;
  background: rgba(255, 255, 255, 0.1);
}

.timeline-item {
  position: relative;
}

.time-marker {
  position: absolute;
  left: -20px;
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 10px var(--accent-cyan);
}

.time-period {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent-indigo);
  margin-bottom: 4px;
}

.time-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 4px;
}

.time-detail {
  font-size: 0.88rem;
  color: var(--text-secondary);
}

/* Credentials */
.credential-cards {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.cred-item {
  display: flex;
  gap: 16px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 12px;
  padding: 16px;
  align-items: center;
}

.cred-item.dev-highlight {
  background: rgba(99, 102, 241, 0.08);
  border-color: rgba(99, 102, 241, 0.25);
}

.cred-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 4px 8px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-secondary);
}

.cred-badge.dev {
  background: var(--accent-indigo);
  color: #ffffff;
}

.cred-info h4 {
  font-size: 0.95rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 2px;
}

.cred-info p {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* SECTION 6: CONTACT */
.contact-card-wrapper {
  background: linear-gradient(135deg, rgba(22, 30, 48, 0.9) 0%, rgba(13, 17, 28, 0.95) 100%);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 28px;
  padding: 56px 40px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.contact-pill {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--accent-cyan);
  background: rgba(6, 182, 212, 0.1);
  padding: 4px 12px;
  border-radius: 999px;
}

.contact-title {
  font-family: var(--font-display);
  font-size: 2.2rem;
  font-weight: 800;
  margin: 14px 0 10px;
  color: #ffffff;
}

.contact-sub {
  font-size: 1rem;
  color: var(--text-secondary);
  max-width: 580px;
  margin: 0 auto 40px;
}

.contact-channels-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 48px;
}

.channel-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 16px;
  padding: 24px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: all 0.25s ease;
}

.channel-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.05);
}

.channel-icon {
  font-size: 2rem;
  margin-bottom: 10px;
}

.channel-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.channel-value {
  font-size: 0.95rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 16px;
  word-break: break-all;
}

.copy-btn, .link-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: rgba(99, 102, 241, 0.15);
  border: 1px solid rgba(99, 102, 241, 0.3);
  color: #e0e7ff;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s ease;
}

.copy-btn:hover, .link-btn:hover {
  background: var(--accent-indigo);
  color: #ffffff;
}

/* Quick Inquiry Form */
.quick-inquiry-box {
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 18px;
  padding: 32px;
  max-width: 680px;
  margin: 0 auto;
}

.inquiry-box-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 20px;
  text-align: center;
  color: #ffffff;
}

.inquiry-form {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

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

.inquiry-input, .inquiry-textarea {
  width: 100%;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 10px;
  padding: 12px 16px;
  color: #ffffff;
  font-family: var(--font-sans);
  font-size: 0.92rem;
  outline: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.inquiry-input:focus, .inquiry-textarea:focus {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.15);
}

.inquiry-btn {
  background: linear-gradient(135deg, var(--accent-indigo), var(--accent-cyan));
  color: #ffffff;
  border: none;
  padding: 14px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  transition: opacity 0.2s ease, transform 0.2s ease;
  box-shadow: 0 6px 20px rgba(6, 182, 212, 0.3);
}

.inquiry-btn:hover {
  opacity: 0.95;
  transform: translateY(-2px);
}

/* FOOTER */
.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: #05070a;
  padding: 40px 24px;
}

.footer-inner {
  max-width: 1180px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-left p {
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.footer-sub {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.back-to-card-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #ffffff;
  padding: 10px 18px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.back-to-card-pill:hover {
  background: var(--accent-indigo);
  border-color: var(--accent-indigo);
  transform: translateY(-2px);
}

/* TOAST POPUP */
.toast-popup {
  position: fixed;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: rgba(14, 18, 29, 0.95);
  border: 1px solid var(--accent-cyan);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5), 0 0 15px rgba(6, 182, 212, 0.3);
  backdrop-filter: blur(16px);
  color: #ffffff;
  padding: 12px 24px;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 500;
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 10000;
}

.toast-popup.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* ==========================================================================
   RESPONSIVE DESIGN (Tablets & Mobile)
   ========================================================================== */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .philosophy-cards-grid,
  .curriculum-grid,
  .career-dual-columns {
    grid-template-columns: 1fr;
  }

  .philo-card-wide {
    grid-column: span 1;
  }

  .contact-channels-grid {
    grid-template-columns: 1fr;
  }

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

  .hero-title {
    font-size: 2.3rem;
  }
}

@media (max-width: 640px) {
  :root {
    --card-w: 90vw;
    --card-h: calc(90vw * 0.62);
  }

  .personal-name {
    font-size: 1.6rem;
  }

  .name-en {
    font-size: 0.9rem;
  }

  .headline-catchphrase {
    font-size: 0.82rem;
  }

  .nav-menu {
    display: none; /* simple mobile hide or scroll */
  }

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

  .stage-hud {
    display: none;
  }

  .footer-inner {
    flex-direction: column;
    gap: 20px;
    text-align: center;
  }
}