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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #e3f2fd 0%, #f3e5f5 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    overflow: hidden;
}

.header {
    background: linear-gradient(135deg, #bbdefb 0%, #e1bee7 100%);
    color: #2c3e50;
    padding: 60px 40px;
    text-align: center;
}

.header h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    text-shadow: none;
    color: #2c3e50;
}

.header p {
    font-size: 1.3rem;
    opacity: 0.8;
    margin-bottom: 30px;
    color: #34495e;
}

.version-badge {
    background: rgba(255,255,255,0.7);
    padding: 8px 20px;
    border-radius: 20px;
    display: inline-block;
    font-size: 0.9rem;
    color: #2c3e50;
    border: 1px solid rgba(44, 62, 80, 0.1);
}

.content {
    padding: 50px 40px;
}

.intro {
    text-align: center;
    margin-bottom: 50px;
}

.intro h2 {
    color: #2c3e50;
    font-size: 2.2rem;
    margin-bottom: 20px;
}

.intro p {
    font-size: 1.2rem;
    color: #666;
    max-width: 700px;
    margin: 0 auto;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.feature-card {
    background: #f8f9fa;
    padding: 30px;
    border-radius: 15px;
    border-left: 5px solid #007bff;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.feature-card h3 {
    color: #2c3e50;
    font-size: 1.3rem;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.feature-card p {
    color: #666;
    line-height: 1.6;
}

.feature-list {
    list-style: none;
    margin-top: 15px;
}

.feature-list li {
    color: #555;
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

.feature-list li::before {
    content: '✓';
    color: #28a745;
    font-weight: bold;
    position: absolute;
    left: 0;
}

.download-section {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
    color: white;
    padding: 50px;
    border-radius: 20px;
    text-align: center;
    margin-bottom: 40px;
}

.download-section h3 {
    font-size: 2rem;
    margin-bottom: 20px;
}

.download-section p {
    font-size: 1.1rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.download-btn {
    background: white;
    color: #28a745;
    padding: 15px 40px;
    border: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.3);
    background: #f8f9fa;
}

.download-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.info-card {
    background: rgba(255,255,255,0.1);
    padding: 20px;
    border-radius: 10px;
    text-align: left;
}

.info-card h4 {
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.info-card p {
    font-size: 0.9rem;
    opacity: 0.8;
}

.usage-section {
    background: #f8f9fa;
    padding: 40px;
    border-radius: 15px;
    margin-bottom: 40px;
}

.usage-section h3 {
    color: #2c3e50;
    font-size: 1.8rem;
    margin-bottom: 25px;
    text-align: center;
}

.usage-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 25px;
}

.step {
    text-align: center;
    padding: 20px;
    background: white;
    border-radius: 10px;
}

.step-number {
    background: #007bff;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    margin: 0 auto 15px auto;
}

.step h4 {
    color: #2c3e50;
    margin-bottom: 10px;
}

.step p {
    color: #666;
    font-size: 0.9rem;
}

.footer {
    background: #2c3e50;
    color: white;
    padding: 30px 40px;
    text-align: center;
}

.footer h4 {
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.footer p {
    opacity: 0.8;
    margin-bottom: 10px;
}

.footer a {
    color: #64b5f6;
    text-decoration: none;
}

.footer a:hover {
    text-decoration: underline;
}

.download-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 30px;
}

.download-btn.primary {
    background: linear-gradient(135deg, #007bff 0%, #0056b3 100%);
    color: white;
    border: none;
}

.download-btn.secondary {
    background: white;
    color: #28a745;
    border: 2px solid #28a745;
}

.usage-guide {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.guide-item {
    background: rgba(255,255,255,0.1);
    padding: 20px;
    border-radius: 10px;
    text-align: left;
}

.guide-item h4 {
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.guide-item p {
    font-size: 0.9rem;
    opacity: 0.9;
}

/* 모바일 팁 박스 스타일 - 새로 추가! */
.mobile-tip-box {
    background: linear-gradient(135deg, #E3F2FD 0%, #F3E5F5 100%);
    border: 2px solid #007AFF;
    border-radius: 12px;
    padding: 20px;
    margin: 20px 0;
    text-align: center;
    position: relative;
    box-shadow: 0 4px 12px rgba(0, 122, 255, 0.15);
}

.mobile-tip-box h4 {
    color: #007AFF;
    margin-bottom: 10px;
    font-size: 1.1rem;
    font-weight: 600;
}

.mobile-tip-box p {
    margin: 0;
    line-height: 1.6;
    color: #2c3e50;
}

.mobile-tip-box::before {
    content: '📱';
    position: absolute;
    top: 10px;
    right: 15px;
    font-size: 1.5rem;
    opacity: 0.6;
}

@media (max-width: 768px) {
    .header {
        padding: 40px 20px;
    }

    .header h1 {
        font-size: 2.2rem;
    }

    .content {
        padding: 30px 20px;
    }

    .download-section {
        padding: 30px 20px;
    }

    .features {
        grid-template-columns: 1fr;
    }

    /* 모바일에서 팁 박스 조정 */
    .mobile-tip-box {
        margin: 15px 0;
        padding: 15px;
    }

    .mobile-tip-box h4 {
        font-size: 1rem;
    }

    .mobile-tip-box::before {
        top: 8px;
        right: 12px;
        font-size: 1.2rem;
    }
}