/* *========================================================================
 * CRODE Official Style Sheet
 * Concept: Linear.app Clone & System Engineering Identity
 * Includes: Base, Typography, Animations, Terminal UI, Cards, Footer
 *======================================================================== */

/* --- 1. Variables & Base --- */
:root {
  --linear-bg: #060609;         /* 더 깊은 블랙으로 조정 */
  --linear-heading: #FFFFFF;    /* 메인 타이틀: 완전 흰색 */
  --linear-text: #E1E1E1;       /* 중요 본문: 밝은 회색 (가시성 상향) */
  --linear-text-dim: #999999;   /* 부가 설명: 중간 회색 */
  --linear-primary: #7683FB;    /* 포인트 컬러 (가시성을 위해 톤업된 Linear Purple) */
  --card-bg: rgba(255, 255, 255, 0.03);
  --border-color: rgba(255, 255, 255, 0.08);
}

body {
  font-family: 'Inter', -apple-system, sans-serif;
  background-color: var(--linear-bg);
  color: var(--linear-text);
  overflow-x: hidden;
  margin: 0;
  
  /* 배경 그리드 패턴 (Linear Signature) */
  background-image: 
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  background-position: center center;
}

/* --- 2. Animations --- */
/* 배경 광원 숨쉬는 효과 */
@keyframes pulseGlow {
  0% { transform: translateX(-50%) scale(1); opacity: 0.8; filter: blur(60px); }
  50% { transform: translateX(-50%) scale(1.1); opacity: 1; filter: blur(80px); }
  100% { transform: translateX(-50%) scale(1); opacity: 0.8; filter: blur(60px); }
}

/* 스크롤 등장 애니메이션 */
@keyframes fadeUp {
  0% { opacity: 0; transform: translateY(30px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* 터미널 커서 깜빡임 */
@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

/* 등장 애니메이션 클래스별 지연 적용 */
.hero, .notice-section, .features, .spotlight-section, .tech-stack, .bottom-cta {
  opacity: 0;
  animation: fadeUp 1s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.hero { animation-delay: 0.1s; }
.notice-section { animation-delay: 0.3s; }
.features { animation-delay: 0.5s; }
.spotlight-section { animation-delay: 0.7s; }
.tech-stack { animation-delay: 0.9s; }

/* --- 3. Background Glow --- */
.hero-glow {
  position: absolute;
  top: -10%;
  left: 50%;
  transform: translateX(-50%);
  width: 80vw;
  height: 80vh;
  /* 더 강렬하고 복합적인 광원 배치 */
  background: radial-gradient(circle at 50% 50%, rgba(118, 131, 251, 0.15), transparent 60%),
              radial-gradient(circle at 50% 0%, rgba(255, 255, 255, 0.05), transparent 40%);
  z-index: -1;
  pointer-events: none;
  animation: pulseGlow 8s ease-in-out infinite; /* 애니메이션 적용 */
}

/* --- 4. Navigation --- */
.linear-nav {
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.linear-nav .nav-link {
  color: var(--linear-text-dim);
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s ease;
}

.linear-nav .nav-link:hover {
  color: var(--linear-heading);
}

/* --- 5. Typography & Buttons --- */
.main-content {
  padding-top: 160px;
}

/* 메인 타이틀 금속성 그라데이션 */
.linear-heading {
  font-size: clamp(48px, 8vw, 88px);
  line-height: 1.05;
  letter-spacing: -0.04em;
  font-weight: 700;
  background: linear-gradient(180deg, #FFFFFF 0%, rgba(255, 255, 255, 0.5) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.linear-subheading {
  font-size: 20px;
  line-height: 1.6;
  max-width: 600px;
  margin: 0 auto;
  color: var(--linear-text) !important;
  opacity: 1;
}

.linear-btn-primary {
  background-color: var(--linear-primary);
  border: none;
  border-radius: 6px;
  font-weight: 600;
  font-size: 16px;
  padding: 12px 28px;
  color: white;
  box-shadow: 0 4px 20px rgba(118, 131, 251, 0.3);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.linear-btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(118, 131, 251, 0.5);
  background-color: #8A96FC;
}

/* --- 6. Feature Cards & Dynamic Spotlight --- */
.linear-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  backdrop-filter: blur(8px);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden; /* 스포트라이트가 카드를 벗어나지 않도록 */
}

/* JS 연동: 마우스를 따라다니는 스포트라이트 빛 */
.linear-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(
      800px circle at var(--mouse-x, 0) var(--mouse-y, 0),
      rgba(118, 131, 251, 0.08),
      transparent 40%
  );
  z-index: 0;
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.linear-card:hover::before {
  opacity: 1;
}

.linear-card:hover {
  border-color: rgba(118, 131, 251, 0.6);
  background: rgba(255, 255, 255, 0.06);
  transform: translateY(-4px) scale(1.01);
  box-shadow: 0 20px 40px -10px rgba(0,0,0,0.7), 0 0 20px rgba(118, 131, 251, 0.2);
}

.linear-card > .card-body,
.linear-card > .terminal-header,
.linear-card > .terminal-body {
  position: relative;
  z-index: 1; /* 빛 위로 콘텐츠를 올림 */
}

.card-title {
  color: var(--linear-heading);
  letter-spacing: -0.01em;
}

/* --- 7. Utility & Overrides (Visibility) --- */
.card-text.text-muted {
  color: var(--linear-text-dim) !important;
}

.notice-text p, .notice-text li {
  color: var(--linear-text) !important;
}

.text-white-50 {
  color: var(--linear-text-dim) !important;
}

.text-accent {
  color: var(--linear-primary) !important;
}

/* --- 8. Terminal UI & Tech Stack --- */
.terminal-window {
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.8), 0 0 0 1px rgba(255, 255, 255, 0.1);
}

.cursor-blink {
  animation: blink 1s step-end infinite;
}

.tech-badge {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  color: var(--linear-text-dim);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-family: 'JetBrains Mono', monospace;
  transition: all 0.2s ease;
}

.tech-badge:hover {
  background: rgba(118, 131, 251, 0.1);
  border-color: var(--linear-primary);
  color: var(--linear-heading);
  transform: translateY(-2px);
}

.bottom-cta {
  padding-top: 80px;
  padding-bottom: 80px;
}

/* --- 9. Footer --- */
footer {
  margin-top: 100px;
  padding-top: 40px;
  border-top: 1px solid var(--border-color) !important;
}

.footer-text {
  color: #8A8F98;
  letter-spacing: 0.02em;
}

.footer-link {
  color: #8A8F98;
  text-decoration: none;
  font-family: 'JetBrains Mono', monospace; 
  transition: color 0.2s ease, text-shadow 0.2s ease;
}

.footer-link:hover {
  color: var(--linear-heading);
  text-shadow: 0 0 8px rgba(255, 255, 255, 0.4);
}