:root {
    --bg-base: #141619;
    --bg-surface: #1c1f24;
    --bg-elevated: #252a31;
    --bg-elevated-hover: #2e343d;
    --border-subtle: #2f353d;
    --border-accent: #5c4d3c;

    --accent-warm: #d4a373;
    --accent-warm-hover: #e0b388;
    --accent-warm-subtle: rgba(212, 163, 115, 0.12);
    --accent-gold: #c9935a;

    --square-light: #ede0c8;
    --square-dark: #b58863;
    --board-border: #3b3024;

    --text-primary: #f0ebe4;
    --text-secondary: #a9b0ba;
    --text-muted: #717882;

    --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: ui-monospace, "Cascadia Code", "Source Code Pro", Menlo, Consolas, monospace;

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;

    --shadow-soft: 0 4px 16px rgba(0, 0, 0, 0.35);
}

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

html {
    font-size: 16px;
    color-scheme: dark;
}

body {
    background-color: var(--bg-base);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.app-header {
    background-color: var(--bg-surface);
    border-bottom: 1px solid var(--border-subtle);
    padding: 0.85rem 1.5rem;
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.65rem;
}

.brand h1 {
    font-size: 1.35rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

.brand-badge {
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-sm);
    background-color: var(--accent-warm-subtle);
    color: var(--accent-warm);
    border: 1px solid var(--border-accent);
}

.header-status {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Main Layout */
.app-main {
    flex: 1;
    padding: 2rem 1.5rem;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
}

.game-layout {
    display: grid;
    grid-template-columns: minmax(320px, 600px) minmax(280px, 1fr);
    gap: 2rem;
    align-items: stretch;
}

.board-column {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    min-width: 0;
}

/* Schachbrett-Bereich */
.board-section {
    width: 100%;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    box-shadow: var(--shadow-soft);
    display: flex;
    justify-content: center;
}

.board-wrapper {
    width: 100%;
    max-width: 560px;
}

.board-frame {
    display: flex;
    align-items: stretch;
    gap: 0.35rem;
}

.coord-ranks {
    display: grid;
    grid-template-rows: repeat(8, 1fr);
    align-items: center;
    justify-items: center;
    width: 1.25rem;
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    user-select: none;
}

.board-grid-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    min-width: 0;
}

.chessboard {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    grid-template-rows: repeat(8, 1fr);
    width: 100%;
    aspect-ratio: 1 / 1;
    border: 2px solid var(--border-accent);
    border-radius: var(--radius-sm);
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
}

.square {
    aspect-ratio: 1 / 1;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    user-select: none;
}

.square::before,
.square::after {
    content: "";
    position: absolute;
    pointer-events: none;
}

.square::before {
    z-index: 1;
    inset: 0;
}

.square.highlight::before {
    background-color: rgba(67, 137, 127, 0.3);
}

.square.selected::before {
    background-color: rgba(212, 163, 115, 0.22);
    box-shadow: inset 0 0 0 4px var(--accent-warm);
}

.square.highlight.selected::before {
    background:
        linear-gradient(
            rgba(212, 163, 115, 0.18),
            rgba(212, 163, 115, 0.18)
        ),
        rgba(67, 137, 127, 0.3);
}

.square.legal-target::after {
    z-index: 2;
    width: 24%;
    height: 24%;
    top: 38%;
    left: 38%;
    border-radius: 50%;
    background-color: rgba(30, 39, 43, 0.58);
    box-shadow: 0 0 0 1px rgba(240, 235, 228, 0.35);
}

.square.legal-capture::after {
    z-index: 2;
    inset: 7%;
    border: 3px solid #713a2e;
    border-radius: 50%;
    box-shadow: inset 0 0 0 2px rgba(240, 235, 228, 0.78);
}

.square.light {
    background-color: var(--square-light);
}

.square.dark {
    background-color: var(--square-dark);
}

.piece {
    width: 86%;
    height: 86%;
    object-fit: contain;
    display: block;
    pointer-events: none;
    user-select: none;
    filter: drop-shadow(0 1px 2px rgba(0, 0, 0, 0.35));
}

.coord-files {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    align-items: center;
    justify-items: center;
    height: 1.25rem;
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    user-select: none;
}

/* Steuerungspanel */
.controls-panel {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    min-width: 0;
}

.controls-panel.training-layout {
    display: grid;
    grid-template-rows: auto minmax(0, 1fr);
    min-height: 0;
}

.status-card.training-status {
    display: flex;
    flex: 1;
    flex-direction: column;
    min-height: 0;
}

.status-content {
    min-height: 0;
}

.training-status .status-content {
    flex: 1;
    overflow-y: auto;
    overscroll-behavior: contain;
}

.status-card {
    width: 100%;
}

.panel-card {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 1rem;
    box-shadow: var(--shadow-soft);
}

.panel-card h2 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 0.7rem;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-subtle);
    padding-bottom: 0.5rem;
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--accent-warm);
}

.panel-info {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.85rem;
}

.panel-card fieldset {
    display: grid;
    gap: 0.4rem;
    border: 0;
    padding: 0 0.5rem;
    margin-bottom: 0.85rem;
}

.panel-card fieldset[hidden] {
    display: none;
}

.panel-card legend {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.35rem;
}

.panel-card fieldset label {
    display: flex;
    align-items: center;
    gap: 0.55rem;
    color: var(--text-secondary);
}

.panel-card select {
    width: 100%;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    padding: 0.45rem 0.55rem;
    background-color: var(--bg-elevated);
    color: var(--text-primary);
    font: inherit;
}

.active-mode {
    margin-top: 0.6rem;
    color: var(--accent-warm);
    font-weight: 600;
}

.mode-note {
    margin-top: 0.35rem;
    margin-bottom: 0;
}

.game-clock {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.game-clock[hidden] {
    display: none;
}

.clock-player {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    padding: 0.55rem 0.7rem;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background-color: var(--bg-base);
    color: var(--text-secondary);
}

.clock-player time {
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 1.2rem;
    font-variant-numeric: tabular-nums;
    font-weight: 700;
}

.clock-player.is-active {
    border-color: var(--accent-warm);
    background-color: var(--accent-warm-subtle);
}

.clock-player.is-active time {
    color: var(--accent-warm);
}

#time-control-label {
    grid-column: 1 / -1;
    color: var(--text-muted);
    font-size: 0.78rem;
    text-align: center;
}

#elo-slider {
    width: 100%;
    accent-color: var(--accent-warm);
}

.training-tools {
    display: grid;
    gap: 0.6rem;
    padding: 0.8rem;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background-color: var(--bg-base);
}

.training-tools[hidden],
.analysis-result[hidden] {
    display: none;
}

.training-tools h3 {
    font-size: 1rem;
}

.analysis-actions {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    grid-auto-rows: minmax(3rem, 1fr);
    gap: 0.35rem;
}

.analysis-actions button {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    min-width: 0;
    min-height: 3rem;
    border: 1px solid var(--border-accent);
    border-radius: var(--radius-sm);
    padding: 0.3rem 0.4rem;
    background: var(--bg-elevated);
    color: var(--text-primary);
    font: inherit;
    line-height: 1.25;
    text-align: center;
    overflow-wrap: anywhere;
    cursor: pointer;
}

.analysis-actions button:hover:not(:disabled) {
    border-color: var(--accent-warm);
    background-color: var(--bg-elevated-hover);
}

.analysis-actions button:disabled {
    cursor: not-allowed;
    opacity: 0.55;
}

.analysis-status,
.analysis-result,
.hint-result {
    color: var(--text-secondary);
    white-space: normal;
    overflow-wrap: anywhere;
}

.analysis-result {
    display: grid;
    gap: 0.25rem;
}

.analysis-result p:first-child {
    color: var(--accent-warm);
    font-weight: 600;
}

.square.hint-source {
    box-shadow: inset 0 0 0 4px #4ba3d8;
}

.square.hint-target {
    box-shadow: inset 0 0 0 4px #72c48d;
}

.start-button,
.resign-button,
.undo-button,
#export-pgn-btn {
    display: block;
    border: 1px solid var(--border-accent);
    border-radius: var(--radius-md);
    padding: 0.6rem 0.85rem;
    background-color: var(--accent-warm-subtle);
    color: var(--accent-warm);
    font: inherit;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 120ms ease, border-color 120ms ease;
}

.status-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.status-actions > button {
    flex: 1 1 9rem;
    min-width: 0;
}

.start-button:hover:not(:disabled),
.resign-button:hover:not(:disabled),
.undo-button:hover:not(:disabled),
#export-pgn-btn:hover:not(:disabled) {
    background-color: var(--bg-elevated-hover);
    border-color: var(--accent-warm);
}

.start-button:disabled,
.resign-button:disabled,
.undo-button:disabled,
#export-pgn-btn:disabled,
.panel-card input:disabled,
.panel-card select:disabled {
    cursor: not-allowed;
    opacity: 0.55;
}

.move-history-scroll {
    height: min(42vh, 360px);
    max-height: min(42vh, 360px);
    min-height: 3.25rem;
    overflow-y: auto;
    overscroll-behavior: contain;
    border-radius: var(--radius-sm);
    background-color: var(--bg-base);
}

.move-history {
    width: 100%;
    table-layout: fixed;
    border-collapse: collapse;
    font-family: var(--font-mono);
    font-size: 0.88rem;
    font-variant-numeric: tabular-nums;
}

.move-history .move-number-column {
    width: 2.9rem;
}

.move-history thead th:nth-child(3n + 1) {
    white-space: nowrap;
}

.move-history th,
.move-history td {
    padding: 0.5rem 0.65rem;
    text-align: left;
    border-bottom: 1px solid var(--border-subtle);
    overflow-wrap: anywhere;
}

.move-history thead {
    position: sticky;
    top: 0;
    z-index: 1;
    background-color: var(--bg-elevated);
    color: var(--text-secondary);
    font-family: var(--font-sans);
    font-size: 0.78rem;
    font-weight: 600;
}

.move-history tbody .move-number {
    color: var(--text-muted);
    font-weight: 500;
}

.move-history tbody td {
    color: var(--text-primary);
}

.move-history .last-move {
    background-color: var(--accent-warm-subtle);
    color: var(--accent-warm);
}

.move-history .empty-moves td {
    padding: 1rem 0.65rem;
    color: var(--text-muted);
    text-align: center;
    font-family: var(--font-sans);
}

.resign-dialog {
    width: min(28rem, calc(100vw - 2rem));
    max-width: calc(100vw - 2rem);
    margin: auto;
    padding: 0;
    border: 1px solid var(--border-accent);
    border-radius: var(--radius-lg);
    background-color: var(--bg-surface);
    color: var(--text-primary);
    box-shadow: var(--shadow-soft);
}

.resign-dialog::backdrop {
    background-color: rgba(0, 0, 0, 0.65);
}

.resign-dialog-content {
    display: grid;
    gap: 1rem;
    padding: 1.25rem;
}

.resign-dialog-content h2 {
    font-size: 1.1rem;
    font-weight: 600;
}

.resign-dialog-content p {
    color: var(--text-secondary);
}

.resign-dialog-actions {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 0.6rem;
}

.resign-dialog-actions button {
    flex: 1 1 8rem;
    min-width: 0;
    min-height: 2.75rem;
    border: 1px solid var(--border-accent);
    border-radius: var(--radius-md);
    padding: 0.6rem 0.85rem;
    font: inherit;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 120ms ease, border-color 120ms ease;
}

.dialog-cancel-button {
    background-color: var(--bg-elevated);
    color: var(--text-primary);
}

.dialog-confirm-button {
    background-color: var(--accent-warm-subtle);
    color: var(--accent-warm);
}

.resign-dialog-actions button:hover {
    background-color: var(--bg-elevated-hover);
    border-color: var(--accent-warm);
}

.resign-dialog-actions button:focus-visible {
    outline: 2px solid var(--accent-warm);
    outline-offset: 2px;
}

/* Footer */
.app-footer {
    background-color: var(--bg-surface);
    border-top: 1px solid var(--border-subtle);
    padding: 1rem 1.5rem;
    text-align: center;
    font-size: 0.82rem;
    color: var(--text-muted);
}

.app-footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.4rem 1.25rem;
    margin-top: 0.5rem;
}

.app-footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
}

.app-footer-links a:hover,
.app-footer-links a:focus-visible {
    color: var(--accent-warm);
    text-decoration: underline;
}

/* Responsive Anpassung */
@media (max-width: 860px) {
    .game-layout {
        grid-template-columns: minmax(0, 1fr);
        gap: 1.5rem;
    }

    .app-main {
        padding: 1rem 0.75rem;
    }

    .board-section {
        padding: 0.85rem;
    }

    .analysis-actions {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .controls-panel.training-layout {
        display: flex;
    }

    .status-card.training-status {
        flex: initial;
    }

    .training-status .status-content {
        overflow-y: visible;
    }
}

@media (max-width: 480px) {
    .coord-ranks {
        width: 1rem;
        font-size: 0.68rem;
    }

    .coord-files {
        height: 1rem;
        font-size: 0.68rem;
    }

    .board-section {
        padding: 0.5rem;
    }

    .status-actions > button {
        flex-basis: 100%;
    }

    .move-history th,
    .move-history td {
        padding: 0.45rem 0.2rem;
        font-size: 0.72rem;
    }

    .move-history .move-number-column {
        width: 2.1rem;
    }

    .resign-dialog-actions {
        flex-direction: column-reverse;
    }

    .resign-dialog-actions button {
        flex-basis: auto;
        width: 100%;
    }
}