:root {
    --bg-color: #121212;
    --surface-color: #1e1e1e;
    --text-primary: #e0e0e0;
    --text-secondary: #a0a0a0;
    --border-color: #333333;
    --solved-color: #00e676;
    --solved-bg: #1b5e20;
    --missing-bg: #2c2c2c;
    --missing-hover: #b71c1c;
    --void-bg: #0a0a0a;
}

body {
    font-family: "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    margin: 0;
    padding: 20px;
}

h1 {
    text-align: center;
    font-weight: 300;
    letter-spacing: 2px;
    margin-bottom: 10px;
}

/* STATS BAR */
.stats-bar {
    background-color: var(--surface-color);
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    display: flex;
    justify-content: space-around;
    align-items: center;
    border: 1px solid var(--border-color);
    flex-wrap: wrap;
    gap: 15px;
}

.stat-item {
    text-align: center;
}

.stat-val {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--solved-color);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-transform: uppercase;
}

/* Secondary / subordinate stat for tests */
.stat-item-secondary {
    border-left: 1px solid var(--border-color);
    padding-left: 20px;
    opacity: 0.75;
}

.stat-val-secondary {
    color: var(--text-secondary);
    font-size: 1.15rem;
}

.stat-val-sub {
    font-size: 0.85rem;
    color: #777;
}

/* CONTROLS */
.controls-bar {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 20px;
    flex-wrap: wrap;
    align-items: center;
}

select,
button {
    background-color: #333;
    color: #fff;
    border: 1px solid #555;
    padding: 10px 15px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
}

button:hover {
    background-color: #444;
}

.btn-random {
    background-color: #c62828;
    border-color: #b71c1c;
}

.btn-random:hover {
    background-color: #d32f2f;
}

/* RANDOM RESULT BOX */
#random-result {
    display: none;
    max-width: 600px;
    margin: 0 auto 20px auto;
    padding: 15px;
    background-color: #263238;
    border-left: 5px solid #ffca28;
    border-radius: 4px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    animation: fadeIn 0.3s ease;
}

#random-result a {
    color: #4fc3f7;
    font-weight: bold;
    text-decoration: none;
}

#random-result a:hover {
    text-decoration: underline;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* LEGEND */
.legend {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 20px;
    font-size: 0.9em;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 8px;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.solved {
    background-color: var(--solved-color);
    box-shadow: 0 0 5px var(--solved-color);
}

.dot.missing {
    background-color: var(--missing-bg);
    border: 1px solid #555;
}

/* TABLE */
.table-container {
    overflow-x: auto;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    background-color: var(--surface-color);
    margin-bottom: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
    min-width: 800px;
}

th,
td {
    padding: 8px 4px;
    text-align: center;
    border: 1px solid var(--border-color);
}

th {
    background-color: #252526;
    color: var(--text-primary);
    position: sticky;
    top: 0;
    z-index: 10;
}

.row-header {
    background-color: #2d2d30;
    position: sticky;
    left: 0;
    z-index: 10;
    text-align: left;
    padding-left: 15px;
    font-family: "Courier New", monospace;
    border-right: 2px solid var(--border-color);
    width: 120px;
    min-width: 120px;
}

.cell {
    height: 25px;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    color: inherit;
}

td.solved-cell {
    background-color: var(--solved-bg);
}

td.solved-cell .cell {
    color: var(--solved-color);
    font-weight: bold;
}

td.missing-cell {
    background-color: var(--missing-bg);
}

td.void-cell {
    background-color: var(--void-bg);
    border-color: #222;
}

.test-label {
    font-size: 10px;
    font-weight: bold;
    color: #757575;
    user-select: none;
}

/* EXTRA SETS (DEMO / TRIAL) */
.extra-sets-section {
    margin-top: 35px;
    border-top: 1px solid var(--border-color);
    padding-top: 25px;
}

.extra-set-title {
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 1.5px;
    color: var(--text-secondary);
    margin-bottom: 12px;
    text-align: left;
    text-transform: uppercase;
}

.extra-table-container {
    width: fit-content;
    max-width: 100%;
    margin-bottom: 25px;
}

.extra-table {
    width: auto !important;
    min-width: unset !important;
}

.extra-table th,
.extra-table td {
    min-width: 36px;
    width: 36px;
}

.extra-table .row-header {
    width: 120px;
    min-width: 120px;
}

/* Dimming effect for filter */
td.dimmed {
    opacity: 0.15;
    filter: grayscale(100%);
}

td.highlight {
    border: 2px solid #ffca28;
    transform: scale(1.1);
    z-index: 5;
    transition: 0.2s;
}

/* LIST MODE */
.list-container {
    max-width: 800px;
    margin: 0 auto;
    background-color: var(--surface-color);
    padding: 20px;
    border-radius: 8px;
}

.generic-file-list {
    list-style: none;
    padding: 0;
}

.generic-file-list li {
    padding: 8px;
    border-bottom: 1px solid #333;
}

.generic-file-list a {
    color: var(--text-primary);
    text-decoration: none;
    display: block;
}

.generic-file-list a:hover {
    color: var(--solved-color);
}

.hidden-item {
    display: none;
}