* {
    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, #2ecc71 0%, #27ae60 100%);
    min-height: 100vh;
}

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

/* Simple Header */
header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    text-align: center;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

.logo {
    font-size: 2.2rem;
    font-weight: bold;
    color: #e74c3c;
    text-decoration: none;
}

/* Main Content */
main {
    background: white;
    margin-top: 1rem;
    border-radius: 20px 20px 0 0;
    box-shadow: 0 -10px 30px rgba(0, 0, 0, 0.1);
    padding: 2rem 0;
}

.section {
    padding: 2rem 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 2rem;
    color: #c0392b;
    position: relative;
}

.section-title::after {
    content: '';
    width: 80px;
    height: 4px;
    background: linear-gradient(45deg, #e74c3c, #c0392b);
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
}

/* About Section */
.about-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: justify;
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 15px;
    margin-bottom: 3rem;
}

.about-content p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
}

/* Search Bar */
.search-container {
    text-align: center;
    margin: 2rem 0;
    position: sticky;
    top: 20px;
    z-index: 100;
}

.search-bar {
    width: 100%;
    max-width: 500px;
    padding: 1rem 1.5rem;
    font-size: 1.1rem;
    border: 2px solid #2ecc71;
    border-radius: 50px;
    outline: none;
    transition: all 0.3s ease;
    background: white;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.search-bar:focus {
    transform: scale(1.02);
    box-shadow: 0 10px 30px rgba(46, 204, 113, 0.3);
}

/* Meeting Schedule Section */
.meeting-schedule {
    background: #f8f9fa;
    padding: 3rem 0;
    margin: 2rem 0;
}

.meetings-grid {
    display: grid;
    gap: 2rem;
    margin-top: 2rem;
}

.meeting-card {
    background: white;
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
    border-left: 6px solid #2ecc71;
}

.meeting-card:hover {
    transform: translateY(-5px);
}

.meeting-header {
    display: flex;
    justify-content: between;
    align-items: center;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.meeting-date {
    background: linear-gradient(45deg, #2ecc71, #27ae60);
    color: white;
    padding: 0.5rem 1.5rem;
    border-radius: 25px;
    font-weight: bold;
    font-size: 1.1rem;
}

.meeting-session {
    font-size: 1.3rem;
    color: #333;
    font-weight: 600;
}

.problems-in-meeting {
    margin-top: 1.5rem;
}

.problems-in-meeting h4 {
    color: #27ae60;
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.problem-item {
    background: #f8f9fa;
    padding: 1rem;
    border-radius: 10px;
    margin-bottom: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.problem-info {
    flex: 1;
}

.problem-name {
    font-weight: 600;
    color: #333;
    margin-bottom: 0.3rem;
}

.problem-topic {
    font-size: 0.9rem;
    color: #666;
    background: #e9ecef;
    padding: 0.2rem 0.8rem;
    border-radius: 15px;
    display: inline-block;
}

.problem-links {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.link-btn {
    padding: 0.4rem 1rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.leetcode-btn { background: #ffa116; color: white; }
.code-btn { background: #28a745; color: white; }

.link-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.pdf-link {
    background: #e74c3c;
    color: white;
    padding: 0.8rem 2rem;
    border-radius: 10px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    margin-top: 1rem;
}

.pdf-link:hover {
    background: #c0392b;
    transform: translateY(-2px);
}

/* Topics Section */
.topics-section {
    padding: 3rem 0;
}

.topic-filter {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.topic-btn {
    background: #e9ecef;
    border: none;
    padding: 0.7rem 1.5rem;
    border-radius: 25px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
}

.topic-btn.active {
    background: #2ecc71;
    color: white;
}

.topic-btn:hover {
    transform: translateY(-2px);
}

.topic-problems {
    display: none;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.topic-problems.active {
    display: grid;
}

.topic-problem-card {
    background: white;
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease;
    border-left: 4px solid #2ecc71;
}

.topic-problem-card:hover {
    transform: translateY(-3px);
}

.difficulty {
    padding: 0.3rem 1rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: bold;
    margin-left: 1rem;
}

.easy { background: #d4edda; color: #155724; }
.medium { background: #fff3cd; color: #856404; }
.hard { background: #f8d7da; color: #721c24; }

/* Footer */
footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 2rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .meeting-header {
        flex-direction: column;
        text-align: center;
    }

    .problem-item {
        flex-direction: column;
        text-align: center;
    }

    .topic-filter {
        justify-content: center;
    }

    .topic-problems {
        grid-template-columns: 1fr;
    }

    .code-modal-content {
        max-width: 95vw;
        max-height: 90vh;
    }
    
    .code-modal-header::before {
        left: 10px;
        width: 10px;
        height: 10px;
        box-shadow: 16px 0 0 #ffbd2e, 32px 0 0 #28ca42;
    }

    .code-modal-title {
        font-size: 12px;
        margin-left: 50px;
    }
}

/* Search highlight */
.highlight {
    background: yellow;
    padding: 2px 4px;
    border-radius: 3px;
}

.hidden {
    display: none !important;
}

/* Mac Vim Style Code Modal */
.code-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.code-modal-content {
    background: #272822;
    border-radius: 8px;
    max-width: 900px;
    max-height: 85vh;
    width: 90%;
    position: relative;
    box-shadow: 0 15px 50px rgba(0, 0, 0, 0.7);
    border: 1px solid #3a3a3a;
}

.code-modal-header {
    background: linear-gradient(135deg, #2d2d2d 0%, #1a1a1a 100%);
    color: #e5e5e5;
    padding: 12px 20px;
    border-radius: 8px 8px 0 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid #444;
    position: relative;
}

/* Mac window controls */
.code-modal-header::before {
    content: '';
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #ff5f57;
    box-shadow: 20px 0 0 #ffbd2e, 40px 0 0 #28ca42;
}

.code-modal-title {
    font-size: 13px;
    font-weight: 500;
    color: #a8a8a8;
    margin-left: 70px;
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
}

.code-modal-close {
    background: transparent;
    color: #666;
    border: none;
    font-size: 18px;
    cursor: pointer;
    padding: 5px 8px;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.code-modal-close:hover {
    background: #333;
    color: #fff;
}

.code-modal-body {
    padding: 0;
    overflow: hidden;
}


/* Custom scrollbar */
.code-content::-webkit-scrollbar {
    width: 12px;
}

.code-content::-webkit-scrollbar-track {
    background: #2d2d2d;
}

.code-content::-webkit-scrollbar-thumb {
    background: #555;
    border-radius: 6px;
}

.code-content::-webkit-scrollbar-thumb:hover {
    background: #666;
}

/* Reduced horizontal and vertical spacing in code popup */
.code-content {
    background: #272822;
    color: #f8f8f2;
    padding: 10px 12px;  /* Reduced from 20px to 10px 12px */
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', 'Consolas', monospace;
    font-size: 12px;     /* Reduced from 13px to 12px */
    line-height: 0.8;    /* Reduced from 1.6 to 1.2 for tighter line spacing */
    max-height: 70vh;
    overflow-y: auto;
    white-space: pre;
    position: relative;
    border-radius: 0 0 8px 8px;
}

.code-line {
    display: block;
    position: relative;
    padding-left: 40px;  /* Reduced from 50px to 40px */
    margin-bottom: 0;    /* Remove any bottom margin */
}

.code-line::before {
    content: attr(data-line);
    position: absolute;
    left: 0;
    top: 0;
    width: 30px;         /* Reduced from 40px to 30px */
    text-align: right;
    color: #75715e;
    font-size: 11px;     /* Reduced from 12px to 11px */
    user-select: none;
    padding-right: 6px;  /* Reduced from 10px to 6px */
}


/* Monokai-style Python syntax highlighting */
.keyword { color: #f92672; font-weight: bold; }
.string { color: #e6db74; }
.comment { color: #75715e; font-style: italic; }
.number { color: #ae81ff; }
.builtin { color: #66d9ef; }
.function { color: #a6e22e; }
.class-name { color: #66d9ef; font-weight: bold; }
.decorator { color: #a6e22e; }
.operator { color: #f92672; }
.bracket { color: #f8f8f2; }
.paren { color: #f8f8f2; }
.brace { color: #f8f8f2; }

.loading-spinner {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 3rem;
    color: #a0a0a0;
    background: #272822;
}

.spinner {
    border: 3px solid #333;
    border-top: 3px solid #f92672;
    border-radius: 50%;
    width: 24px;
    height: 24px;
    animation: spin 1s linear infinite;
    margin-right: 12px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}


/* Difficulty badges */
.difficulty {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-left: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.02em;
}

.difficulty.easy {
    background: #d1f2eb;
    color: #0d7345;
    border: 1px solid #a3e2c7;
}

.difficulty.medium {
    background: #fef9e7;
    color: #b7791f;
    border: 1px solid #f9e79f;
}

.difficulty.hard {
    background: #fdeaea;
    color: #cb4b4b;
    border: 1px solid #f1948a;
}

/* Responsive adjustment for mobile */
@media (max-width: 768px) {
    .difficulty {
        display: block;
        margin: 0.3rem 0 0 0;
        width: fit-content;
    }
}