:root {
    --bg-color: #f8f9fa;
    --text-color: #212529;
    --header-bg: #ffffff;
    --card-bg: #ffffff;
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --border-color: #dee2e6;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --header-bg: #1e1e1e;
    --card-bg: #1e1e1e;
    --primary-color: #378afe;
    --secondary-color: #a0a0a0;
    --border-color: #333333;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.5);
}

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

body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
    line-height: 1.6;
}

.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation & Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 5%;
    background-color: var(--header-bg);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 30px;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 20px;
}

.main-nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.2s;
}

.main-nav ul li a:hover {
    color: var(--primary-color);
}

.nav-controls {
    display: flex;
    gap: 10px;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    display: flex;
    align-items: center;
    gap: 10px;
    background: linear-gradient(45deg, #007bff, #6610f2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 80px 20px;
    background: linear-gradient(135deg, rgba(0,123,255,0.05) 0%, rgba(102,16,242,0.05) 100%);
    border-radius: 0 0 50px 50px;
    margin-bottom: 40px;
}

.hero h1 {
    font-size: 2.8rem;
    margin-bottom: 15px;
    color: var(--text-color);
}

/* Info Section (Guide) */
.info-section {
    padding: 60px 0;
    margin-bottom: 40px;
}

.section-header {
    text-align: center;
    margin-bottom: 40px;
}

.section-header h2 {
    font-size: 2.2rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.guide-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.guide-card {
    background-color: var(--card-bg);
    padding: 30px;
    border-radius: 20px;
    text-align: center;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    transition: transform 0.3s;
}

.guide-card:hover {
    transform: translateY(-10px);
}

.guide-card i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.guide-card h3 {
    margin-bottom: 15px;
    font-size: 1.4rem;
}

/* Filter & Grid */
.filter-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    gap: 20px;
    flex-wrap: wrap;
    background: var(--card-bg);
    padding: 20px;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

.search-box {
    position: relative;
    flex: 1;
    min-width: 250px;
}

.search-box i {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--secondary-color);
}

.search-box input {
    width: 100%;
    padding: 12px 15px 12px 45px;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-color);
    color: var(--text-color);
}

.brand-filters {
    display: flex;
    gap: 10px;
}

.filter-btn {
    padding: 8px 16px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.2s;
}

.filter-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.laptop-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 25px;
    margin-bottom: 50px;
}

/* Footer */
footer {
    background-color: var(--header-bg);
    padding: 60px 0 20px;
    border-top: 1px solid var(--border-color);
    margin-top: 60px;
}

.footer-content {
    text-align: center;
}

.footer-links {
    margin: 20px 0;
}

.footer-links a {
    margin: 0 15px;
    color: var(--secondary-color);
    text-decoration: none;
    font-size: 0.9rem;
}

.disclaimer {
    font-size: 0.8rem;
    color: var(--secondary-color);
    max-width: 800px;
    margin: 20px auto 0;
    opacity: 0.8;
}

/* Modals */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: var(--card-bg);
    margin: 10% auto;
    padding: 40px;
    border-radius: 20px;
    width: 80%;
    max-width: 700px;
    position: relative;
    box-shadow: 0 20px 40px rgba(0,0,0,0.2);
}

.policy-text {
    text-align: left;
    background: var(--bg-color);
    padding: 20px;
    border-radius: 10px;
    margin-top: 20px;
}

.close-modal, .close-privacy {
    position: absolute;
    right: 20px;
    top: 15px;
    font-size: 28px;
    cursor: pointer;
}

/* Utility */
button {
    cursor: pointer;
}

#reset-compare {
    background-color: #ff4757;
    color: white;
    border: none;
}

#reset-compare:hover {
    background-color: #ff6b81;
}

.theme-btn {
    font-size: 1.2rem;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}