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

:root {
    --black: #000000;
    --white: #ffffff;
    --gray-100: #f5f5f5;
    --gray-200: #eeeeee;
    --gray-300: #e0e0e0;
    --gray-400: #bdbdbd;
    --gray-500: #9e9e9e;
    --gray-600: #757575;
    --gray-700: #616161;
    --gray-800: #424242;
    --gray-900: #212121;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background-color: var(--white);
    color: var(--black);
    line-height: 1.5;
}

.app {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 200px;
    background-color: var(--black);
    color: var(--white);
    padding: 20px;
    flex-shrink: 0;
}

.sidebar h1 {
    font-size: 1.25rem;
    margin-bottom: 30px;
    font-weight: 600;
}

.sidebar nav {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.nav-btn {
    background: transparent;
    border: 1px solid var(--gray-600);
    color: var(--gray-400);
    padding: 10px 15px;
    text-align: left;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.nav-btn:hover {
    border-color: var(--white);
    color: var(--white);
}

.nav-btn.active {
    background-color: var(--white);
    color: var(--black);
    border-color: var(--white);
}

/* Main Content */
.content {
    flex: 1;
    padding: 30px 40px;
    max-width: 1200px;
}

.view {
    display: none;
}

.view.active {
    display: block;
}

h2 {
    font-size: 1.5rem;
    margin-bottom: 25px;
    font-weight: 600;
}

h3 {
    font-size: 1.1rem;
    margin: 20px 0 10px;
    font-weight: 600;
}

/* Forms */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    font-size: 0.9rem;
}

input[type="text"],
select {
    width: 100%;
    max-width: 300px;
    padding: 10px 12px;
    border: 2px solid var(--gray-300);
    font-size: 1rem;
    background-color: var(--white);
}

input[type="text"]:focus,
select:focus {
    outline: none;
    border-color: var(--black);
}

.radio-group {
    display: flex;
    gap: 20px;
}

.radio-group label {
    display: flex;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-weight: normal;
}

input[type="radio"] {
    width: 16px;
    height: 16px;
    accent-color: var(--black);
}

#player-names {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 10px;
    max-width: 650px;
}

#player-names input {
    width: 100%;
    max-width: none;
}

.btn-primary {
    background-color: var(--black);
    color: var(--white);
    border: none;
    padding: 12px 30px;
    font-size: 1rem;
    cursor: pointer;
    font-weight: 500;
    transition: background-color 0.2s;
}

.btn-primary:hover {
    background-color: var(--gray-800);
}

.btn-secondary {
    background-color: var(--white);
    color: var(--black);
    border: 2px solid var(--black);
    padding: 10px 25px;
    font-size: 0.9rem;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-secondary:hover {
    background-color: var(--black);
    color: var(--white);
}

.hidden {
    display: none !important;
}

#current-tournament {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid var(--gray-300);
}

#current-tournament-info {
    margin-bottom: 15px;
    color: var(--gray-700);
}

/* Crosstable */
.sort-options {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.sort-options label {
    font-size: 0.9rem;
    color: var(--gray-600);
}

.sort-btn {
    background: var(--white);
    border: 1px solid var(--gray-400);
    padding: 6px 14px;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s;
}

.sort-btn:hover {
    border-color: var(--black);
}

.sort-btn.active {
    background-color: var(--black);
    color: var(--white);
    border-color: var(--black);
}

.table-container {
    overflow-x: auto;
}

table {
    border-collapse: collapse;
    width: 100%;
    font-size: 0.9rem;
}

th, td {
    border: 1px solid var(--gray-300);
    padding: 8px 12px;
    text-align: center;
}

th {
    background-color: var(--gray-100);
    font-weight: 600;
}

#crosstable th:first-child,
#crosstable td:first-child {
    text-align: left;
    font-weight: 500;
}

#crosstable .diagonal {
    background-color: var(--black);
}

#crosstable .result-cell {
    min-width: 30px;
}

#crosstable .points-col,
#crosstable .sb-col,
#crosstable .rank-col {
    font-weight: 600;
    background-color: var(--gray-100);
}

/* Schedule */
.round-navigation {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin-bottom: 25px;
}

.nav-arrow {
    background: var(--white);
    border: 2px solid var(--black);
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.2s;
}

.nav-arrow:hover {
    background-color: var(--black);
    color: var(--white);
}

.nav-arrow:disabled {
    border-color: var(--gray-400);
    color: var(--gray-400);
    cursor: not-allowed;
}

.nav-arrow:disabled:hover {
    background-color: var(--white);
    color: var(--gray-400);
}

#round-indicator {
    font-size: 1.1rem;
    font-weight: 600;
    min-width: 100px;
    text-align: center;
}

#schedule-table {
    max-width: 500px;
}

#schedule-table td {
    padding: 10px 15px;
}

#schedule-table .white-player,
#schedule-table .black-player {
    text-align: left;
    min-width: 150px;
}

#schedule-table .result-input {
    width: 50px;
    padding: 6px;
    text-align: center;
    border: 2px solid var(--gray-300);
    font-size: 1rem;
}

#schedule-table .result-input:focus {
    outline: none;
    border-color: var(--black);
}

#schedule-table .bye-row {
    background-color: var(--gray-200);
    color: var(--gray-600);
}

#schedule-table .bye-row .result-input {
    background-color: var(--gray-200);
    border-color: var(--gray-300);
    color: var(--gray-500);
}

.result-legend {
    margin-top: 20px;
    font-size: 0.85rem;
    color: var(--gray-600);
}

.result-legend strong {
    color: var(--black);
}

/* Tournament List */
.tournament-card {
    border: 2px solid var(--gray-300);
    padding: 16px 20px;
    margin-bottom: 12px;
    cursor: pointer;
    transition: border-color 0.2s;
    max-width: 500px;
}

.tournament-card:hover {
    border-color: var(--black);
}

.tournament-card-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 8px;
}

.tournament-card-header h3 {
    font-size: 1rem;
    margin: 0;
}

.tournament-meta {
    font-size: 0.8rem;
    color: var(--gray-500);
}

.tournament-card-body {
    display: flex;
    gap: 16px;
    font-size: 0.85rem;
    color: var(--gray-600);
    margin-bottom: 10px;
}

.progress-bar {
    height: 4px;
    background-color: var(--gray-200);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background-color: var(--black);
    transition: width 0.3s;
}

.muted {
    color: var(--gray-500);
    font-size: 0.9rem;
}

/* Sidebar navigation */
.nav-separator {
    height: 1px;
    background-color: var(--gray-600);
    margin: 12px 0;
}

.nav-label {
    display: block;
    color: var(--gray-400);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Danger zone */
.danger-zone {
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--gray-300);
}

.danger-zone h3 {
    color: #c62828;
}

.danger-zone p {
    margin-bottom: 12px;
}

.btn-danger {
    background-color: #c62828;
    color: var(--white);
    border: none;
    padding: 10px 25px;
    font-size: 0.9rem;
    cursor: pointer;
    font-weight: 500;
    transition: background-color 0.2s;
}

.btn-danger:hover {
    background-color: #b71c1c;
}

/* Responsive */
@media (max-width: 768px) {
    .app {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        padding: 15px;
    }

    .sidebar h1 {
        margin-bottom: 15px;
    }

    .sidebar nav {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .nav-btn {
        flex: 1;
        text-align: center;
        min-width: 100px;
    }

    .content {
        padding: 20px;
    }

    #player-names {
        grid-template-columns: 1fr;
    }

    .radio-group {
        flex-direction: column;
        gap: 10px;
    }
}