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

:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-card: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --accent-blue: #3b82f6;
    --accent-purple: #8b5cf6;
    --accent-pink: #ec4899;
    --accent-green: #10b981;
    --accent-amber: #f59e0b;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
}

body.dark-mode {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-card: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.3);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

/* Header */
.header {
    margin-bottom: 3rem;
}

.header-content {
    text-align: center;
    margin-bottom: 2rem;
}

.title {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Controls */
.controls {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.search-container {
    position: relative;
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
}

.search-input {
    width: 100%;
    padding: 1rem 3rem 1rem 1.5rem;
    font-size: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    background: var(--bg-card);
    color: var(--text-primary);
    transition: all 0.3s ease;
}

.search-input:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.search-icon {
    position: absolute;
    right: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.2rem;
}

.filter-buttons {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    justify-content: center;
}

.filter-btn {
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--border-color);
    background: var(--bg-card);
    color: var(--text-primary);
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.filter-btn:hover {
    border-color: var(--accent-blue);
    transform: translateY(-2px);
}

.filter-btn.active {
    background: var(--accent-blue);
    color: white;
    border-color: var(--accent-blue);
}

.action-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.action-btn {
    padding: 0.75rem 1.5rem;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.action-btn:hover {
    background: var(--bg-card);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

/* Results Info */
.results-info {
    text-align: center;
    margin-bottom: 2rem;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Essay Grid */
.essay-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.essay-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

.essay-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-blue);
}

.essay-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.essay-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    line-height: 1.3;
}

.category-badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 600;
    color: white;
    white-space: nowrap;
}

.essay-meta {
    display: flex;
    gap: 1rem;
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin-bottom: 0.75rem;
}

.essay-preview {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    overflow-y: auto;
    padding: 2rem;
}

.modal.active {
    display: flex;
    align-items: flex-start;
    justify-content: center;
}

.modal-content {
    background: var(--bg-card);
    border-radius: 16px;
    max-width: 900px;
    width: 100%;
    margin: 2rem auto;
    position: relative;
    box-shadow: var(--shadow-lg);
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-close {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--text-secondary);
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.modal-close:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.modal-header {
    padding: 2rem 3rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.modal-title {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 1rem;
    padding-right: 2rem;
}

.modal-meta {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
    color: var(--text-secondary);
}

.source-link {
    color: var(--accent-blue);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
}

.source-link:hover {
    color: var(--accent-purple);
}

.modal-body {
    padding: 2rem 3rem 3rem;
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--text-primary);
    white-space: normal;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .title {
        font-size: 2rem;
    }

    .essay-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .filter-buttons {
        flex-direction: column;
    }

    .filter-btn {
        width: 100%;
    }

    .action-buttons {
        flex-direction: column;
    }

    .action-btn {
        width: 100%;
    }

    .modal-content {
        margin: 0;
        border-radius: 0;
        min-height: 100vh;
    }

    .modal-header,
    .modal-body {
        padding: 1.5rem;
    }

    .modal-title {
        font-size: 1.5rem;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}