/* Basic Style Reset & Font Configuration */
:root {
    --primary-color: #00a8ff; /* Accent Blue */
    --background-color: #1a1a1a; /* Dark Gray Background */
    --surface-color: #2c2c2c;   /* Card Background */
    --text-color: #e0e0e0;       /* Main Text Color */
    --header-font: 'Roboto Mono', monospace;
    --body-font: 'Roboto', sans-serif;
}

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

body {
    font-family: var(--body-font);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.7;
    padding: 20px;
}

.container {
    max-width: 1100px;
    margin: 40px auto;
    padding: 40px;
    background-color: var(--surface-color);
    border: 1px solid #444;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.4);
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

h1 a {
  color: inherit; /* 부모(h1)의 글자 색상을 그대로 물려받습니다. */
  text-decoration: none; /* 밑줄을 제거합니다. */
}

/* Header */
header {
    text-align: center;
    margin-bottom: 50px;
    border-bottom: 1px solid var(--primary-color);
    padding-bottom: 20px;
}


header h1 {
    font-family: var(--header-font);
    font-size: 2.5em;
    color: var(--primary-color);
    margin-bottom: 10px;
    text-shadow: 0 0 5px rgba(0, 168, 255, 0.5);
}
/* --- Header Logo & Title Alignment --- */

.header-main {
    display: flex;
    align-items: center;
    justify-content: center;
}

.header-logo {
    height: 50px; /* 로고 크기 조절 */
    width: auto;
    margin-right: 15px; /* 로고와 타이틀 사이 간격 */
}

header .subtitle {
    font-family: var(--header-font);
    font-size: 1.2em;
    color: #bbb;
}

/* Main Content Sections */
main section {
    margin-bottom: 50px;
}

main h2 {
    font-size: 1.8em;
    color: var(--primary-color);
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid #555;
}

main p {
    font-size: 1.05em;
    margin-bottom: 15px;
}
main p strong {
    color: #c0c0c0;
}

/* Course Outline Section */
.day-card {
    background-color: #333;
    border: 1px solid #444;
    border-left: 5px solid var(--primary-color);
    border-radius: 5px;
    padding: 20px;
    margin-bottom: 20px;
}

.day-card h3 {
    font-size: 1.4em;
    margin-bottom: 15px;
    color: #f0f0f0;
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: 12px 25px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    font-size: 1.1em;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    text-align: center;
}

.button-group {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap; /* Allow buttons to wrap on smaller screens */
    margin: 30px 0;
}

.btn-github {
    background-color: #444;
    color: #fff;
    border-color: #666;
}

.btn-github:hover {
    background-color: #fff;
    color: #111;
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(255, 255, 255, 0.1);
}

.btn-submit {
    background-color: var(--primary-color);
    color: #fff;
    border-color: var(--primary-color);
}

.btn-submit:hover {
    background-color: #007bb5;
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0, 168, 255, 0.3);
}

.btn-material {
    background-color: transparent;
    color: #ccc;
    border: 1px solid #666;
    padding: 8px 18px;
    font-size: 0.9em;
    margin-top: 10px;
}

.btn-material:hover {
    background-color: var(--primary-color);
    color: #fff;
    border-color: var(--primary-color);
}

/* --- Disabled Button Style --- */

.btn-disabled {
    background-color: #555; /* Dark gray background */
    border-color: #777;
    color: #999; /* Faded text color */
    cursor: not-allowed; /* Shows a "not allowed" icon on hover */
    pointer-events: none; /* Disables all click events */
}

/* Optional: remove any hover effects from the disabled button */
.btn-disabled:hover {
    transform: none;
    box-shadow: none;
    background-color: #555;
    border-color: #777;
}


.note {
    text-align: center;
    font-size: 0.9em;
    color: #aaa;
    margin-top: 30px;
}

/* Footer */
footer {
    text-align: center;
    margin-top: 50px;
    padding-top: 20px;
    border-top: 1px solid #444;
    font-size: 0.9em;
    color: #888;
}

/* JS Loaded Class */
.container.loaded {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive YouTube Video Container */
.video-container {
    position: relative;
    overflow: hidden;
    width: 100%;
    padding-top: 56.25%; /* 16:9 Aspect Ratio */
    margin: 25px 0; /* Adds some space above and below the video */
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0; /* Ensures no border appears */
}

/* --- Main Navigation Bar Styles --- */
.main-nav {
    width: 100%;
    background-color: #222; /* A slightly darker background for contrast */
    border-radius: 5px;
    margin-bottom: 50px; /* Space between nav and main content */
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center; /* Center the menu items */
    flex-wrap: wrap; /* Allow items to wrap on smaller screens */
}

.main-nav li a {
    display: block;
    color: var(--text-color);
    text-decoration: none;
    padding: 15px 20px;
    font-family: var(--header-font);
    font-size: 1em;
    text-transform: uppercase;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Style for the link of the page you're currently on */
.main-nav li a.current,
.main-nav li a:hover {
    background-color: var(--primary-color);
    color: #fff;
}


.responsive-image {
  width: 100%; 
  height: auto; 
  display: block; 
  margin-bottom: 25px;
}




#questions{
    text-align: center;
    margin-top: 50px;
}

.contact-email{
    margin-top: 20px;
    font-size: 1.2em;
    font-family: var(--header-font);
}

.contact-email a {
    color: var(--primary-color);
    text-decoration: none;
    padding: 10px 15px;
    border: 1px solid var(--primary-color);
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
}

.contact-email a:hover {
    background-color: var(--primary-color);
    color: #fff;
}

#registration-details{
    text-align: center;
    margin-top: 50px;
}

.registration-link{
    margin-top: 20px;
    font-size: 1.2em;
    font-family: var(--header-font);
}

.registration-link a {
    color: var(--primary-color);
    text-decoration: none;
    padding: 10px 15px;
    border: 1px solid var(--primary-color);
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
}

.registration-link a:hover {
    background-color: var(--primary-color);
    color: #fff;
}



/* --- Overview Page List Styles --- */

.details-list {
    list-style: none; /* Removes the default bullet points */
    padding-left: 0;
    margin-top: 20px;
}

.details-list li {
    background-color: #333;
    padding: 15px;
    margin-bottom: 10px;
    border-radius: 5px;
    border-left: 4px solid var(--primary-color);
    font-size: 1.05em;
}

.details-list li strong {
    color: #f0f0f0; /* Makes the label stand out a bit */
    margin-right: 8px;
}


/* --- Schedule Page Table Styles --- */

.schedule-table {
    width: 100%;
    margin-top: 30px;
    border-collapse: collapse; /* Removes space between borders */
    font-size: 1.05em;
}

.schedule-table th,
.schedule-table td {
    padding: 15px;
    text-align: left;
    border: 1px solid #444; /* Grid lines for the table */
}

.schedule-table thead {
    background-color: #333;
}

.schedule-table th {
    font-family: var(--header-font);
    font-size: 1.1em;
    color: var(--primary-color);
}

/* Adds a subtle striping effect to the table rows for readability */
.schedule-table tbody tr:nth-child(even) {
    background-color: #303030;
}

/* --- Sponsors Page Styles --- */

.sponsor-grid {
    display: grid;
    /* Creates a responsive grid that fits as many logos as possible per row */
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px; /* Space between logos */
    margin-top: 40px;
    align-items: center;
}

.sponsor-card {
    background-color: #ffffff; /* Logos often look best on a white background */
    border-radius: 8px;
    padding: 20px;
    height: 150px; /* All cards will have the same height */
    display: flex;
    justify-content: center;
    align-items: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.sponsor-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 168, 255, 0.2);
}

.sponsor-card img {
    width: 100%;
    height: 100%;
    max-height: 120px; /* All cards will have the same height */
    /* This is the key property! It scales the image to fit without stretching */
    object-fit: contain;
}


/* --- Hacker/Forensics Theme Enhancements --- */

/* 1. Subtle Circuit Board Background for the whole page */
body {
    background-image: url('../images/background_main.png');
    background-image: linear-gradient(rgba(0, 0, 0, 0.65), rgba(0, 0, 0, 0.65)), url('../images/background_main.png');
    background-color: #000000; /* Fallback for when the image is loading */
    background-position: top right; /* Anchors the image to the top right corner */
    background-repeat: no-repeat; /* Prevents the image from tiling */
    background-attachment: fixed; /* Keeps the background static when scrolling */
    background-size: cover; /* Ensures the image covers the whole screen */
}

/* 2. Scanline Overlay Effect */
body::after {
    content: ' ';
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: repeating-linear-gradient(0deg, transparent, rgba(255, 255, 255, 0.05) 1px, transparent 2px);
    z-index: 9999;
    pointer-events: none;
    opacity: 0.5;
}

/* 3. Glitch Effect for the Main Header (h1) */
header h1 {
    position: relative;
    text-shadow: 0 0 5px rgba(0, 168, 255, 0.5), 0 0 10px rgba(0, 168, 255, 0.3);
    /* MODIFIED: Runs for 3s, once, and holds the final state */
    animation: glitch-flicker 4s 1 forwards;
}

header h1::before,
header h1::after {
    content: attr(data-text);
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #2c2c2c;
    overflow: hidden;
}

header h1::before {
    left: 2px;
    text-shadow: -2px 0 #ff00c1;
    /* MODIFIED: Runs for 2s, once, and holds the final state */
    animation: glitch-anim-1 4s 1 forwards;
}

header h1::after {
    left: -2px;
    text-shadow: -2px 0 #00fff9;
    /* MODIFIED: Runs for 3s, once, and holds the final state */
    animation: glitch-anim-2 4s 1 forwards;
}

/* Keyframe animations for the glitch effect */
@keyframes glitch-anim-1 {
    0% { clip-path: inset(15% 0 86% 0); }
    20% { clip-path: inset(48% 0 23% 0); }
    40% { clip-path: inset(23% 0 18% 0); }
    60% { clip-path: inset(80% 0 12% 0); }
    80% { clip-path: inset(54% 0 8% 0); }
    90% { clip-path: inset(34% 0 55% 0); }
    /* MODIFIED: Ensures the glitch is gone at the end */
    95%, 100% { clip-path: inset(50% 50% 50% 50%); } 
}

@keyframes glitch-anim-2 {
    0% { clip-path: inset(79% 0 12% 0); }
    20% { clip-path: inset(10% 0 5% 0); }
    40% { clip-path: inset(89% 0 2% 0); }
    60% { clip-path: inset(34% 0 45% 0); }
    80% { clip-path: inset(5% 0 89% 0); }
    90% { clip-path: inset(70% 0 20% 0); }
    /* MODIFIED: Ensures the glitch is gone at the end */
    95%, 100% { clip-path: inset(50% 50% 50% 50%); }
}

@keyframes glitch-flicker {
    0% { opacity: 1; }
    49% { opacity: 1; }
    50% { opacity: 0.8; }
    51% { opacity: 1; }
    99%, 100% { opacity: 1; }
    /* 100% { opacity: 0.9; } */
}


/* --- Glowing Neon Hover for Cards --- */
.team-card:hover,
.sponsor-card:hover {
    transform: translateY(-5px); /* Keep the lift effect */
    /* Add a multi-layered shadow to create a glow */
    box-shadow: 0 0 15px rgba(0, 168, 255, 0.4), 
                0 0 5px rgba(0, 168, 255, 0.7);
}




/* --- Blinking Cursor for Headings (Class-based) --- */
.blinking-cursor {
    position: relative; /* Needed for the pseudo-element */
    display: inline-block; /* Ensures the cursor is right after the text */
}

.blinking-cursor::after {
    content: '_';
    font-weight: bold;
    color: var(--primary-color);
    margin-left: 8px;
    animation: blink 1s step-end infinite;
}

/* Keyframe animation for the blinking effect (if not already present) */
@keyframes blink {
    50% {
        opacity: 0;
    }
}

/* Keyframe animation for the blinking effect */
@keyframes blink {
    50% {
        opacity: 0;
    }
}
/* --- Terminal Window Style for Lists --- */
.details-list li {
    background-color: #000000; /* Black background */
    border: 1px solid rgba(0, 168, 255, 0.3); /* Faint blue border */
    border-left: 3px solid var(--primary-color); /* Keep the colored left border */
    font-family: var(--header-font); /* Use the monospaced font */
    padding: 15px;
    margin-bottom: 10px;
    border-radius: 0px; /* Sharp corners */
    font-size: 1em;
    line-height: 1.6;
}

.details-list li strong {
    color: var(--primary-color); /* Make labels blue */
    margin-right: 8px;
}