:root {
    --primary: #4F46E5;
    --primary-dark: #4338CA;
    --text-main: #1F2937;
    --text-sub: #6B7280;
    --bg-light: #F9FAFB;
    --white: #FFFFFF;
}

/* 기본 초기화 */
* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Noto Sans KR', sans-serif; }
body { 
    color: var(--text-main); 
    line-height: 1.6; 
    overflow-x: hidden; /* 가로 스크롤 절대 방지 */
    background: #fff;
    width: 100%;
}
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }

/* === 네비게이션 === */
.navbar { 
    position: fixed; top: 0; left: 0; width: 100%; 
    background: rgba(255,255,255,0.95); 
    backdrop-filter: blur(10px); 
    z-index: 1000; 
    border-bottom: 1px solid #eee; 
    height: 60px;
    display: flex; align-items: center;
}
.nav-container { 
    width: 100%; max-width: 1100px; margin: 0 auto; 
    display: flex; justify-content: space-between; align-items: center; 
    padding: 0 20px; 
}
.logo { 
    display: flex; align-items: center; gap: 8px; 
    font-size: 18px; font-weight: 900; color: var(--primary); 
    letter-spacing: -0.5px; flex-shrink: 0;
}
.logo img { width: 28px; height: 28px; }
.nav-buttons { display: flex; gap: 8px; align-items: center; flex-shrink: 0; }
.btn-login { font-size: 14px; color: var(--text-sub); font-weight: 500; white-space: nowrap; }
.btn-start { 
    background: var(--primary); color: white; 
    padding: 8px 16px; border-radius: 20px; 
    font-size: 14px; font-weight: 700; 
    transition: 0.2s; white-space: nowrap;
}
.btn-start:hover { background: var(--primary-dark); }

/* === 히어로 섹션 === */
.hero { 
    max-width: 1100px; margin: 0 auto; 
    padding: 120px 20px 60px; 
    display: flex; align-items: center; justify-content: space-between; 
    gap: 40px; 
    min-height: auto; 
}
.hero-content { flex: 1; min-width: 0; }
.hero-content h1 { 
    font-size: 42px; font-weight: 900; line-height: 1.2; margin-bottom: 20px; word-break: keep-all; 
}
.hero-content .highlight { color: var(--primary); }
.hero-content p { font-size: 18px; color: var(--text-sub); margin-bottom: 30px; word-break: keep-all; }
.btn-hero { 
    display: inline-block; 
    background: var(--text-main); color: white; 
    padding: 15px 32px; border-radius: 30px; 
    font-size: 18px; font-weight: 700; 
    transition: 0.3s; 
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}
.btn-hero:hover { background: black; transform: translateY(-3px); }

/* 목업 카드 */
.hero-image { flex: 1; display: flex; justify-content: center; width: 100%; }
.mockup-card { 
    width: 320px; max-width: 100%;
    background: white; border-radius: 24px; 
    box-shadow: 0 20px 50px rgba(0,0,0,0.15); 
    border: 1px solid #eee; overflow: hidden; 
    transform: rotate(-3deg); transition: 0.5s; 
}
.mockup-card:hover { transform: rotate(0deg) scale(1.02); }
.mockup-header { background: #f3f4f6; padding: 12px 15px; display: flex; gap: 6px; }
.dot { width: 8px; height: 8px; border-radius: 50%; }
.red { background: #ff5f56; } .yellow { background: #ffbd2e; } .green { background: #27c93f; }
.mockup-body { padding: 20px; display: flex; flex-direction: column; gap: 12px; }
.mock-row { 
    display: flex; align-items: center; gap: 10px; 
    padding: 12px; border-radius: 12px; 
    background: #fff; border: 1px solid #eee; 
    font-weight: 600; font-size: 14px; 
    overflow: hidden; 
}
.text { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.friend-row { background: #EEF2FF; border-color: #C7D2FE; }
.badge { background: var(--primary); color: white; font-size: 10px; padding: 2px 6px; border-radius: 4px; flex-shrink: 0; }
.mock-comment { display: flex; align-items: center; gap: 10px; margin-top: 5px; }
.avatar { width: 28px; height: 28px; background: #ddd; border-radius: 50%; flex-shrink: 0; }
.bubble { background: #F3F4F6; padding: 8px 12px; border-radius: 0 12px 12px 12px; font-size: 12px; color: #555; }

/* === 특징 섹션 === */
.features { background: var(--bg-light); padding: 80px 20px; }
.feature-container { 
    max-width: 1100px; margin: 0 auto; 
    display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); 
    gap: 30px; 
}
.feature-item { 
    background: white; padding: 30px; border-radius: 20px; 
    text-align: center; box-shadow: 0 4px 20px rgba(0,0,0,0.03); 
    transition: 0.3s; 
}
.icon-box { font-size: 40px; margin-bottom: 15px; }
.feature-item h3 { font-size: 20px; margin-bottom: 8px; font-weight: 800; }
.feature-item p { color: var(--text-sub); font-size: 15px; word-break: keep-all; }

/* === 쇼케이스 섹션 (PC 기본값) === */
.showcase { padding: 80px 20px; overflow: hidden; }
.showcase-content { 
    max-width: 900px; margin: 0 auto; 
    display: flex; align-items: center; justify-content: space-between; 
    gap: 50px; 
}
.showcase-text { flex: 1; min-width: 0; }
.showcase-text h2 { font-size: 32px; font-weight: 800; line-height: 1.3; margin-bottom: 20px; word-break: keep-all; }
.showcase-text p { color: var(--text-sub); font-size: 16px; word-break: keep-all; }

.showcase-visual { 
    flex: 1; position: relative; height: 240px; min-width: 300px;
    display: flex; justify-content: center; align-items: center; 
}
.stat-card { 
    position: absolute; background: white; 
    padding: 20px 30px; border-radius: 20px; 
    box-shadow: 0 10px 40px rgba(0,0,0,0.1); 
    display: flex; flex-direction: column; gap: 5px; 
    border: 1px solid #eee;
}
.card-1 { top: 20px; left: 10px; animation: float 4s ease-in-out infinite; z-index: 2; }
.card-2 { bottom: 20px; right: 10px; animation: float 4s ease-in-out infinite 1s; z-index: 1; }
.card-3 { bottom: 60px; right: 145px; animation: float 4s ease-in-out infinite 2s; z-index: 1; }
.stat-card span { font-size: 13px; color: #888; }
.stat-card strong { font-size: 28px; color: var(--primary); }

@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-10px); } }

/* === CTA 섹션 === */
.cta-section { background: var(--primary); color: white; text-align: center; padding: 80px 20px; }
.cta-content { max-width: 600px; margin: 0 auto; }
.cta-section h2 { font-size: 30px; margin-bottom: 15px; font-weight: 800; word-break: keep-all; }
.cta-section p { margin-bottom: 30px; opacity: 0.9; font-size: 16px; word-break: keep-all; }
.btn-cta { 
    background: white; color: var(--primary); 
    padding: 16px 40px; border-radius: 40px; 
    font-size: 18px; font-weight: 800; 
    transition: 0.3s; display: inline-block; 
}

/* === 푸터 === */
footer { background: #111; color: #888; padding: 40px 20px; text-align: center; font-size: 13px; }
.footer-logo { display: flex; justify-content: center; align-items: center; gap: 8px; color: white; font-weight: 800; font-size: 16px; margin-bottom: 15px; }
.footer-logo img { width: 20px; height: 20px; }
.footer-links { margin-top: 15px; display: flex; justify-content: center; gap: 15px; }


/* =========================================================
   [모바일 반응형 - 768px 이하]
   ========================================================= */
@media (max-width: 768px) {
    /* 네비게이션 정리 */
    .nav-container { padding: 0 15px; }
    .btn-login { display: none; }
    
    /* 히어로 섹션 세로 정렬 */
    .hero { 
        flex-direction: column; text-align: center; 
        padding-top: 90px; padding-bottom: 40px;
        gap: 40px; 
    }
    .hero-content h1 { font-size: 30px; }
    .hero-content p { font-size: 15px; margin-bottom: 25px; }
    .mockup-card { 
        width: 100%; max-width: 300px; margin: 0 auto;
        transform: none !important; /* 회전 제거 */
    }

    .features { padding: 50px 20px; }
    .feature-container { grid-template-columns: 1fr; gap: 20px; }
    
    /* [수정됨] 쇼케이스 섹션: 겹침 문제 완벽 해결 */
    .showcase { padding: 50px 20px; }
    .showcase-content { flex-direction: column; gap: 40px; }
    .showcase-text { text-align: center; }
    
    .showcase-visual { 
        /* 부모 컨테이너 크기 및 정렬 재설정 */
        width: 100%; 
        height: auto; 
        min-width: auto;
        display: flex;
        flex-direction: column; /* 세로로 쌓기 */
        align-items: center;
        gap: 15px; /* 카드 사이 간격 */
    }

    .stat-card { 
        /* 절대 위치(absolute) 강제 해제 -> static */
        position: static !important; 
        width: 100%; max-width: 280px; 
        margin: 0 !important;
        animation: none !important; /* 둥둥 뜨는 효과 제거 */
        transform: none !important;
        
        /* PC판 위치값 무력화 */
        top: auto !important; left: auto !important; 
        right: auto !important; bottom: auto !important;
    }
    
    .cta-section h2 { font-size: 24px; }
    .btn-cta { width: 100%; max-width: 300px; font-size: 16px; padding: 14px 20px; }
}

/* 초소형 디바이스 (갤럭시 폴드 커버 등) */
@media (max-width: 360px) {
    .logo-text { display: none; }
    .btn-start { font-size: 12px; padding: 6px 12px; }
    .navbar { height: 50px; }
    .hero { padding-top: 70px; }
    .hero-content h1 { font-size: 24px; }
    .mockup-body { padding: 15px; }
    .stat-card { max-width: 100%; }
}