/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    font-family: 'Noto Sans KR', 'Malgun Gothic', sans-serif;
    font-size: 14px;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.4;
    color: #2c3e50;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
    line-height: 1.7;
}

/* Links */
a {
    color: #3498db;
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #2980b9;
}

/* Lists */
ul, ol {
    list-style: none;
}

/* Images */
img {
    max-width: 100%;
    height: auto;
    vertical-align: middle;
}

/* Forms */
input, textarea, select, button {
    font-family: inherit;
    font-size: inherit;
    line-height: inherit;
}

input[type="text"],
input[type="email"],
input[type="tel"],
textarea,
select {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #ddd;
    border-radius: 4px;
    background-color: #fff;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="tel"]:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border: none;
    border-radius: 4px;
    background-color: #3498db;
    color: #fff;
    font-weight: 600;
    text-align: center;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn:hover {
    background-color: #2980b9;
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.btn_primary {
    background-color: #e74c3c;
}

.btn_primary:hover {
    background-color: #c0392b;
}

.btn_secondary {
    background-color: #95a5a6;
}

.btn_secondary:hover {
    background-color: #7f8c8d;
}

.btn_outline {
    background-color: transparent;
    border: 2px solid #3498db;
    color: #3498db;
}

.btn_outline:hover {
    background-color: #3498db;
    color: #fff;
}

/* Utility Classes */
.blind {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.skip {
    position: absolute;
    top: -9999px;
    left: 0;
    z-index: 9999;
    padding: 8px 16px;
    background-color: #000;
    color: #fff;
    text-decoration: none;
}

.skip:focus {
    top: 0;
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-0 { margin-top: 0 !important; }
.mt-1 { margin-top: 0.5rem !important; }
.mt-2 { margin-top: 1rem !important; }
.mt-3 { margin-top: 1.5rem !important; }
.mt-4 { margin-top: 2rem !important; }

.mb-0 { margin-bottom: 0 !important; }
.mb-1 { margin-bottom: 0.5rem !important; }
.mb-2 { margin-bottom: 1rem !important; }
.mb-3 { margin-bottom: 1.5rem !important; }
.mb-4 { margin-bottom: 2rem !important; }

.pt-0 { padding-top: 0 !important; }
.pt-1 { padding-top: 0.5rem !important; }
.pt-2 { padding-top: 1rem !important; }
.pt-3 { padding-top: 1.5rem !important; }
.pt-4 { padding-top: 2rem !important; }

.pb-0 { padding-bottom: 0 !important; }
.pb-1 { padding-bottom: 0.5rem !important; }
.pb-2 { padding-bottom: 1rem !important; }
.pb-3 { padding-bottom: 1.5rem !important; }
.pb-4 { padding-bottom: 2rem !important; }

/* Container */
.inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

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

/* Section Headers */
.sect_head {
    text-align: center;
    margin-bottom: 3rem;
}

.sect_head h3 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.sect_head p {
    font-size: 1.125rem;
    color: #7f8c8d;
    margin-bottom: 0;
}

/* Cards */
.card {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

/* Grid System */
.grid {
    display: grid;
    gap: 2rem;
}

.grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

/* Responsive */
@media (max-width: 768px) {
    .inner,
    .sect_inner {
        padding: 0 15px;
    }
    
    .sect_head h3 {
        font-size: 2rem;
    }
    
    .sect_head p {
        font-size: 1rem;
    }
    
    .grid {
        gap: 1.5rem;
    }
    
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
}

/* Animation */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* Loading */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(52, 152, 219, 0.3);
    border-radius: 50%;
    border-top-color: #3498db;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Scroll to top */
.scroll-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
}

.scroll-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-to-top:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
}