:root { 
    --blue: #00aff0; 
    --bg-color: #fff;
    --text-color: #111;
    --header-bg: rgba(255, 255, 255, 0.85);
    --grid-bg: #fff;
    --item-bg: #f9f9f9;
    --brand-color: #bbb;
    --name-color: #333;
    --border-color: #eee;
    --price-color: #000;
    /* Trendy transition timing */
    --theme-transition: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --bg-color: #111;
    --text-color: #f5f5f5;
    --header-bg: rgba(17, 17, 17, 0.85);
    --grid-bg: #111;
    --item-bg: #1a1a1a;
    --brand-color: #666;
    --name-color: #ccc;
    --border-color: #222;
    --price-color: #fff;
}

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

body { 
    background: #000; 
    font-family: 'Pretendard', -apple-system, sans-serif; 
    overflow: hidden; 
    /* Initial section transition remains slow for premium feel */
    transition: background 1.5s ease; 
}

/* 전 페이지 스르륵 전환 효과 */
.section { 
    position: fixed; top: 0; left: 0; width: 100%; height: 100%; 
    opacity: 0; visibility: hidden; 
    transition: opacity 1.5s cubic-bezier(0.4, 0, 0.2, 1), visibility 1.5s;
    display: flex; align-items: center; justify-content: center;
}
.section.active { opacity: 1; visibility: visible; }

/* [1] 인트로 */
#intro { 
    background: #000 url('bg.jpg') no-repeat center center;
    background-size: contain; z-index: 1000;
}
.logo { font-size: 42px; font-weight: 900; color: #fff; margin-bottom: 30px; letter-spacing: -1.5px; text-align: center; }
.logo span { color: var(--blue); }

.btn { 
    background: var(--blue); color: #fff; border: none; padding: 22px 70px; 
    font-size: 22px; font-weight: 800; border-radius: 60px; cursor: pointer;
    animation: glowingAnimation 1.5s infinite ease-in-out; 
    transition: 0.3s;
}

/* [2] 비디오 섹션 */
#video-layer { background: #000; z-index: 500; }
.video-box { position: relative; width: 100%; max-width: 500px; }
video { 
    width: 100%; display: block; background: #000; 
    mask-image: radial-gradient(circle, black 50%, rgba(0,0,0,0) 100%);
    -webkit-mask-image: radial-gradient(circle, black 50%, rgba(0,0,0,0) 100%);
}

/* [3] 쇼핑몰 - Trendy Transition Refinement */
#shop { 
    display: block; 
    background: var(--bg-color); 
    overflow-y: auto; 
    z-index: 100; 
    flex-direction: column; 
    justify-content: flex-start;
    /* Isolate noise from background-color transition to prevent artifacts */
    position: relative;
    transition: background var(--theme-transition);
}

/* Noise texture separated to avoid "analog TV" blending artifacts during transition */
#shop::before {
    content: "";
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    pointer-events: none;
    z-index: 1;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
    opacity: 0.05;
}

#shop.section { position: absolute; }

.header { 
    position: sticky; top: 0; width: 100%; 
    background: var(--header-bg); 
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--border-color); 
    padding: 20px 30px; 
    z-index: 10001;
    display: flex; align-items: center; justify-content: space-between;
    transition: background var(--theme-transition), border-color var(--theme-transition);
}

.home-logo { 
    color: var(--text-color); 
    font-weight: 900; font-size: 28px; cursor: pointer; letter-spacing: -1px; text-decoration: none;
    transition: color var(--theme-transition);
}
.home-logo span { color: var(--blue); }

.theme-switch-wrapper { display: flex; align-items: center; gap: 12px; }
.theme-char {
    width: 44px; height: 44px;
    display: flex; align-items: center; justify-content: center;
    font-size: 28px;
    background: var(--item-bg);
    border-radius: 50%;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: transform 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275), background var(--theme-transition), box-shadow var(--theme-transition);
}

.theme-label {
    font-size: 14px; font-weight: 800;
    color: var(--text-color);
    transition: color var(--theme-transition);
    user-select: none;
}

.theme-switch {
  display: inline-block; height: 26px; position: relative; width: 50px;
}
.theme-switch input { display:none; }
.slider {
  background-color: #ccc; bottom: 0; cursor: pointer; left: 0; position: absolute; right: 0; top: 0;
  transition: .4s; border-radius: 34px;
}
.slider:before {
  background-color: #fff; bottom: 4px; content: ""; height: 18px; left: 4px; position: absolute;
  transition: .4s; width: 18px; border-radius: 50%;
}
input:checked + .slider { background-color: var(--blue); }
input:checked + .slider:before { transform: translateX(24px); }

.grid { 
    display: grid; 
    grid-template-columns: repeat(5, 1fr);
    gap: 20px 12px;
    max-width: 1400px; margin: 0 auto; padding: 40px 20px;
    position: relative; z-index: 2;
}

/* 프리미엄 엔트리 효과 */
@keyframes imageReveal {
    0% { opacity: 0; filter: blur(20px); transform: translateY(40px) scale(0.95); }
    100% { opacity: 1; filter: blur(0); transform: translateY(0) scale(1); }
}

.item { cursor: pointer; opacity: 0; }
.item.reveal {
    animation: imageReveal 1.2s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

.img-box { 
    width: 100%; aspect-ratio: 3/4; 
    background: var(--item-bg); 
    overflow: hidden; margin-bottom: 12px; 
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.05);
    transition: box-shadow 0.3s ease, background var(--theme-transition);
}
.item:hover .img-box {
    box-shadow: 0 12px 40px rgba(0, 175, 240, 0.2);
}
.item img { width: 100%; height: 100%; object-fit: cover; transition: transform 1.2s cubic-bezier(0.2, 0.8, 0.2, 1); }
.item:hover img { transform: scale(1.08); }

.info { padding: 0 5px; }
.brand { 
    font-size: 10px; color: var(--brand-color); font-weight: bold; margin-bottom: 4px; text-transform: uppercase; 
    transition: color var(--theme-transition);
}
.name { 
    font-size: 13px; color: var(--name-color); font-weight: 400; line-height: 1.4; margin-bottom: 8px; height: 36px; overflow: hidden; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; 
    transition: color var(--theme-transition);
}

.price-area { 
    display: flex; align-items: center; gap: 6px; border-top: 1px solid var(--border-color); padding-top: 8px; 
    transition: border-color var(--theme-transition);
}
.sale { color: var(--blue); font-weight: 800; font-size: 14px; }
.price { 
    color: var(--price-color); font-weight: 800; font-size: 14px; 
    transition: color var(--theme-transition);
}

/* 모바일 대응 */
@media (max-width: 768px) {
    .grid { grid-template-columns: repeat(2, 1fr); }
    .logo { font-size: 32px; }
    .btn { padding: 18px 50px; font-size: 18px; }
    .header { padding: 15px 20px; }
    .theme-char { width: 36px; height: 36px; font-size: 22px; }
}

@keyframes glowingAnimation {
    0% { box-shadow: 0 0 10px rgba(0, 175, 240, 0.7); transform: scale(1); }
    50% { box-shadow: 0 0 40px rgba(0, 175, 240, 0.9), 0 0 80px rgba(0, 175, 240, 1), 0 0 15px #fff; transform: scale(1.05); }
    100% { box-shadow: 0 0 10px rgba(0, 175, 240, 0.7); transform: scale(1); }
}