:root {
    /* Midnight Tech Palette - Refined & Readable */
    --bg: #0f172a; /* Deep Slate */
    --surface: #1e293b; /* Slate 800 */
    --text: #f1f5f9; /* Slate 100 */
    --text-muted: #94a3b8; /* Slate 400 */
    --primary: #38bdf8; /* Sky 400 */
    --accent: #c084fc; /* Purple 400 */
    --highlight: #fbbf24; /* Amber 400 */
    --border: rgba(148, 163, 184, 0.2); /* Muted Slate Border */
    --shadow: rgba(0, 0, 0, 0.4);
    --card-radius: 8px;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    padding: 0;
    font-family: 'Inter', sans-serif;
    background-color: var(--bg);
    /* Subdued tech grid */
    background-image:
        linear-gradient(rgba(56, 189, 248, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(56, 189, 248, 0.03) 1px, transparent 1px);
    background-size: 40px 40px;
    color: var(--text);
    line-height: 1.7;
    transition: background-color 0.4s, color 0.4s;
}

.container {
    max-width: 850px;
    margin: 0 auto;
    padding: 60px 25px;
}

header {
    text-align: center;
    margin-bottom: 80px;
    border-bottom: 1px solid var(--border);
    padding-bottom: 40px;
}

.logo-container {
    margin-bottom: 20px;
}

.logo-container img {
    max-width: 140px;
    /* Subtle glow instead of heavy neon */
    filter: drop-shadow(0 0 5px rgba(56, 189, 248, 0.3));
}

h1 {
    font-family: 'Noto Serif KR', serif;
    font-size: 3rem;
    color: var(--primary);
    margin: 0 0 15px 0;
    text-wrap: balance;
    letter-spacing: -0.02em;
}

.subtitle {
    font-size: 1rem;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 600;
}

section {
    margin-bottom: 80px;
}

h2 {
    font-family: 'Noto Serif KR', serif;
    font-size: 2.2rem;
    color: var(--primary);
    margin-bottom: 40px;
    position: relative;
    display: block;
}

h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--accent);
}

h3 {
    font-family: 'Noto Serif KR', serif;
    font-size: 1.5rem;
    margin-top: 40px;
    color: var(--highlight);
}

p {
    margin-bottom: 24px;
    font-size: 1.05rem;
}

a {
    color: var(--primary);
    text-decoration: none;
    border-bottom: 1px solid var(--border);
    transition: all 0.2s ease;
}

a:hover {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* Program Cards - Glassmorphism with Muted Glow */
.program-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
    margin-top: 30px;
}

.program-grid.full-width {
    grid-template-columns: 1fr;
}

@media (max-width: 800px) {
    .program-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 500px) {
    .program-grid {
        grid-template-columns: 1fr;
    }
}

.card {
    background: var(--surface);
    padding: 30px 25px;
    border-radius: var(--card-radius);
    border: 1px solid var(--border);
    backdrop-filter: blur(8px);
    box-shadow: 0 4px 20px var(--shadow);
    transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    border-color: var(--primary);
    box-shadow: 0 6px 15px var(--shadow);
}

/* Horizontal Card Variant */
.card-horizontal {
    display: flex;
    flex-direction: column;
    gap: 15px;
    padding: 20px 30px;
}

.card-horizontal .card-top {
    display: flex;
    align-items: baseline;
    gap: 15px;
    border-bottom: 1px solid var(--border);
    padding-bottom: 10px;
}

.card-horizontal .card-bottom {
    display: flex;
    align-items: center;
    gap: 30px;
    flex-wrap: wrap;
}

.card-horizontal .card-note {
    font-size: 0.8rem;
    color: var(--text-muted);
    border-top: 1px dashed var(--border);
    padding-top: 10px;
}

.card .code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    color: var(--highlight);
    text-transform: uppercase;
    letter-spacing: 2px;
    display: block;
    margin-bottom: 12px;
}

.card .title {
    font-weight: 600;
    font-size: 1.2rem;
    margin-bottom: 15px;
    display: block;
    color: var(--primary);
}

.card .detail {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.card .price {
    font-weight: 600;
    color: var(--text);
}

/* Requirement List */
.requirement-list {
    list-style: none;
    padding: 0;
}

.requirement-item {
    background: var(--surface);
    margin-bottom: 15px;
    padding: 20px 25px;
    border-radius: var(--card-radius);
    border: 1px solid var(--border);
    display: flex;
    align-items: flex-start;
    box-shadow: 0 2px 10px var(--shadow);
}

.requirement-item span.icon {
    margin-right: 20px;
    font-size: 1.4rem;
    opacity: 0.9;
}

.requirement-item .content strong {
    display: block;
    font-size: 1.1rem;
    color: var(--primary);
    margin-bottom: 4px;
}

/* Process Flow */
.process-flow {
    position: relative;
    padding-left: 40px;
    margin: 40px 0;
}

.process-step {
    position: relative;
    padding-bottom: 40px;
}

.process-step::before {
    content: '';
    position: absolute;
    left: -40px;
    top: 0;
    bottom: 0;
    width: 1px;
    background: var(--border);
}

.process-step:last-child::before {
    display: none;
}

.process-step::after {
    content: '';
    position: absolute;
    left: -45px;
    top: 6px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent);
    border: 2px solid var(--bg);
}

.step-title {
    font-family: 'Noto Serif KR', serif;
    font-weight: 700;
    font-size: 1.2rem;
    display: block;
    margin-bottom: 6px;
    color: var(--primary);
}

.step-desc {
    font-size: 1rem;
    color: var(--text-muted);
}

/* Checklist */
.checklist {
    background: var(--surface);
    padding: 40px;
    border-radius: var(--card-radius);
    border: 1px solid var(--border);
    box-shadow: 0 4px 20px var(--shadow);
}

.checklist-item {
    display: flex;
    align-items: center;
    margin-bottom: 16px;
    font-size: 1rem;
}

.checklist-item input[type="checkbox"] {
    margin-right: 15px;
    width: 20px;
    height: 20px;
    accent-color: var(--accent);
    cursor: pointer;
}

/* Collapsible Table Section */
.collapsible-container {
    margin-top: 40px;
    border: 1px solid var(--border);
    border-radius: var(--card-radius);
    overflow: hidden;
    background: var(--surface);
}

.collapsible-container summary {
    padding: 15px 25px;
    font-weight: 600;
    color: var(--primary);
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background 0.2s;
}

.collapsible-container summary:hover {
    background: rgba(56, 189, 248, 0.1);
}

.collapsible-container summary::after {
    content: '▼';
    font-size: 0.8rem;
    transition: transform 0.3s;
}

.collapsible-container[open] summary::after {
    transform: rotate(180deg);
}

.table-wrapper {
    overflow-x: auto;
    padding: 0 25px 25px 25px;
}

.schedule-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
    font-size: 0.9rem;
    min-width: 700px; /* Ensures it doesn't get too squashed */
}

.schedule-table th, .schedule-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.schedule-table th {
    color: var(--highlight);
    font-weight: 600;
    background: rgba(251, 191, 36, 0.05);
}

.schedule-table tr:last-child td {
    border-bottom: none;
}

.schedule-table ul {
    margin: 0;
    padding-left: 15px;
}

.schedule-table li {
    margin-bottom: 4px;
}

.schedule-table .important-note {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 15px;
    padding-top: 15px;
    border-top: 1px dashed var(--border);
}

/* Note Box */
.note-box {
    background: rgba(192, 132, 252, 0.1);
    border: 1px solid var(--accent);
    padding: 20px 25px;
    border-radius: var(--card-radius);
    font-size: 0.95rem;
    color: var(--text);
    margin: 30px 0;
    position: relative;
}

.note-box::before {
    content: 'NOTICE';
    position: absolute;
    top: -10px;
    left: 20px;
    background: var(--accent);
    color: var(--bg);
    padding: 2px 10px;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 1px;
}

/* Navigation */
nav {
    margin-bottom: 40px;
    text-align: center;
}

nav ul {
    list-style: none;
    padding: 10px 20px;
    margin: 0;
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
    background: rgba(30, 41, 59, 0.5);
    border-radius: 50px;
    border: 1px solid var(--border);
}

nav a {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 600;
    border-bottom: none;
}

nav a:hover {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* Responsive */
@media (max-width: 600px) {
    h1 { font-size: 2.5rem; }
    .container { padding: 40px 15px; }
    .program-grid { grid-template-columns: 1fr; }
    h2 { font-size: 1.8rem; }
    nav ul { flex-direction: column; gap: 10px; border-radius: 10px; }
}

/* Print styles */
@media print {
    body { background: white; color: black; }
    .container { padding: 0; max-width: 100%; }
    .card, .checklist { box-shadow: none; border: 1px solid #ccc; }
    header { margin-bottom: 30px; }
}