/* =====================================================
   AI Studio — Arena 模型评测
   设计语言与 app.css 一致（xAI 风）
   ===================================================== */

/* ============ 主布局 ============ */
.arena-layout {
    display: flex;
    height: 100%;
    background: var(--canvas);
}

.arena-composer {
    width: 360px;
    flex-shrink: 0;
    padding: 28px 24px;
    border-right: 1px solid var(--hairline);
    overflow-y: auto;
    background: var(--canvas);
}

.arena-stage {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    background: var(--canvas);
    overflow: hidden;
}

/* ============ Composer 头部 ============ */
.arena-composer-header {
    margin-bottom: 24px;
}

.arena-composer-title {
    font-family: var(--font-display);
    font-size: 32px;
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -0.8px;
    color: var(--ink);
    margin: 12px 0 8px;
}

.arena-composer-sub {
    font-size: 13px;
    color: var(--body-mid);
    line-height: 1.5;
}

/* ============ Form ============ */
.arena-form {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.arena-form .form-field {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.arena-form .field-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 1.2px;
    text-transform: uppercase;
    color: var(--body-mid);
}

.arena-form .field-textarea {
    width: 100%;
    padding: 10px 12px;
    background: var(--canvas-soft);
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    color: var(--ink);
    font-size: 14px;
    line-height: 1.5;
    resize: vertical;
    min-height: 80px;
    transition: border-color 0.15s;
}

.arena-form .field-textarea:focus {
    outline: none;
    border-color: var(--canvas-mid);
}

.arena-char-count {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--body-mid);
    text-align: right;
    margin-top: 2px;
}

.arena-char-count.over { color: #ff7b72; }

/* ============ 模型选择按钮 ============ */
.arena-pick-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 12px 14px;
    background: var(--canvas-soft);
    border: 1px dashed var(--canvas-mid);
    border-radius: var(--r-sm);
    color: var(--body);
    font-size: 14px;
    text-align: left;
    transition: border-color 0.15s, background 0.15s;
}

.arena-pick-btn:hover {
    border-color: var(--accent-sunset);
    background: var(--canvas-card);
    color: var(--ink);
}

.arena-pick-btn-icon {
    width: 22px;
    height: 22px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--r-sm);
    background: var(--canvas-mid);
    color: var(--accent-sunset);
    font-size: 16px;
    font-weight: 500;
    flex-shrink: 0;
}

.arena-pick-btn-label {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.arena-pick-counter {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.6px;
    color: var(--accent-sunset);
}

.arena-pick-counter.full { color: #ff7b72; }

/* ============ 已选模型 chips ============ */
.arena-pick-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    min-height: 0;
}

.arena-pick-chips:not(:empty) { margin-top: 8px; }

.arena-chip {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 4px 4px 10px;
    background: var(--canvas-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-pill);
    font-size: 12px;
    color: var(--ink);
    transition: border-color 0.15s;
}

.arena-chip:hover { border-color: var(--canvas-mid); }

.arena-chip-name { font-weight: 500; }
.arena-chip-vendor {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--body-mid);
    letter-spacing: 0.4px;
    text-transform: uppercase;
}

.arena-chip-remove {
    width: 18px;
    height: 18px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border-radius: 50%;
    color: var(--body-mid);
    font-size: 13px;
    line-height: 1;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
}

.arena-chip-remove:hover { background: var(--hairline); color: var(--ink); }

/* ============ 附件 ============ */
.arena-attach-row {
    display: flex;
    align-items: center;
    gap: 10px;
}

.arena-attach-btn {
    padding: 6px 12px;
    background: var(--canvas-soft);
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    color: var(--body);
    font-size: 13px;
    cursor: pointer;
    transition: border-color 0.15s, color 0.15s;
}

.arena-attach-btn:hover { border-color: var(--canvas-mid); color: var(--ink); }
.arena-attach-btn span { color: var(--accent-sunset); margin-right: 4px; font-weight: 500; }

.arena-attach-hint {
    font-size: 12px;
    color: var(--body-mid);
}

.arena-attach-preview {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 8px;
}

.arena-attach-thumb {
    position: relative;
    width: 60px;
    height: 60px;
    border-radius: var(--r-sm);
    overflow: hidden;
    background: var(--canvas-card);
    border: 1px solid var(--hairline);
}

.arena-attach-thumb img,
.arena-attach-thumb video,
.arena-attach-thumb audio {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.arena-attach-thumb .attach-type {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--body);
    background: var(--canvas-soft);
}

.arena-attach-thumb .remove {
    position: absolute;
    top: 2px;
    right: 2px;
    width: 18px;
    height: 18px;
    background: rgba(0,0,0,0.7);
    color: white;
    border-radius: 50%;
    font-size: 11px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
}

.arena-multimodal-warn {
    margin-top: 8px;
    padding: 8px 10px;
    background: rgba(255, 122, 24, 0.08);
    border: 1px solid rgba(255, 122, 24, 0.3);
    border-radius: var(--r-sm);
    font-size: 12px;
    color: var(--accent-sunset);
}

/* ============ 匿名开关 ============ */
.arena-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    user-select: none;
    padding: 8px 0;
}

.arena-toggle input { display: none; }

.arena-toggle-box {
    width: 36px;
    height: 20px;
    background: var(--canvas-mid);
    border-radius: var(--r-pill);
    position: relative;
    transition: background 0.15s;
    flex-shrink: 0;
}

.arena-toggle-box::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 16px;
    height: 16px;
    background: white;
    border-radius: 50%;
    transition: transform 0.15s;
}

.arena-toggle input:checked + .arena-toggle-box {
    background: var(--accent-sunset);
}

.arena-toggle input:checked + .arena-toggle-box::after {
    transform: translateX(16px);
}

.arena-toggle-text {
    font-size: 13px;
    color: var(--body);
}

/* ============ 预估消耗 ============ */
.arena-estimate {
    padding: 12px 14px;
    background: var(--canvas-soft);
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.arena-estimate-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    font-size: 13px;
}

.arena-est-label { color: var(--body-mid); }

.arena-est-val {
    font-family: var(--font-mono);
    color: var(--accent-sunset);
    font-variant-numeric: tabular-nums;
}

.arena-est-val.is-low { color: #ff7b72; }

.arena-estimate-warn {
    margin-top: 4px;
    padding-top: 8px;
    border-top: 1px dashed var(--hairline);
    font-size: 12px;
    color: #ff7b72;
}

/* ============ 启动按钮 ============ */
.arena-start-btn {
    margin-top: 4px;
    padding: 12px;
    background: var(--accent-sunset);
    color: var(--on-primary);
    border: none;
    border-radius: var(--r-sm);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: opacity 0.15s, transform 0.05s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.arena-start-btn:hover:not(:disabled) { opacity: 0.9; }
.arena-start-btn:active:not(:disabled) { transform: translateY(1px); }
.arena-start-btn:disabled { background: var(--canvas-mid); color: var(--body-mid); cursor: not-allowed; }
.arena-start-icon { font-size: 16px; }

/* ============ 舞台工具栏 ============ */
.arena-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 24px;
    border-bottom: 1px solid var(--hairline);
    background: var(--canvas);
}

.arena-toolbar-tabs { display: flex; gap: 4px; }

.arena-tab {
    padding: 6px 14px;
    background: transparent;
    border: 1px solid transparent;
    border-radius: var(--r-sm);
    color: var(--body-mid);
    font-size: 13px;
    cursor: pointer;
    transition: color 0.15s, background 0.15s, border-color 0.15s;
}

.arena-tab:hover { color: var(--body); background: var(--canvas-soft); }
.arena-tab.active {
    color: var(--ink);
    background: var(--canvas-soft);
    border-color: var(--hairline);
}

.arena-toolbar-hint {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--body-mid);
    letter-spacing: 0.4px;
}

/* ============ 内容区 ============ */
.arena-content {
    flex: 1;
    overflow-y: auto;
    position: relative;
}

.arena-panel { display: none; padding: 24px; min-height: 100%; }
.arena-panel.active { display: block; }

/* ============ Empty ============ */
.arena-empty {
    max-width: 480px;
    margin: 80px auto;
    text-align: center;
    padding: 40px 24px;
}

.arena-empty .eyebrow-mono { color: var(--body-mid); }

.arena-empty-title {
    font-family: var(--font-display);
    font-size: 20px;
    font-weight: 400;
    color: var(--ink);
    margin: 16px 0 12px;
    line-height: 1.4;
}

.arena-empty-desc {
    font-size: 13px;
    color: var(--body-mid);
    line-height: 1.6;
}

/* ============ Grid + Card ============ */
.arena-grid {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    align-items: start;
}

.arena-card {
    background: var(--canvas-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    display: flex;
    flex-direction: column;
    min-height: 240px;
    overflow: hidden;
    transition: border-color 0.15s;
}

.arena-card.is-error { border-color: rgba(255, 123, 114, 0.4); }
.arena-card.is-done { border-color: var(--hairline); }
.arena-card.is-streaming { border-color: var(--accent-dusk); }

.arena-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 14px;
    border-bottom: 1px solid var(--hairline);
    background: var(--canvas-soft);
}

.arena-card-header-left {
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 0;
    flex: 1;
}

.arena-card-model {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.6px;
    color: var(--body);
    text-transform: uppercase;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    min-width: 0;
    transition: color 0.3s ease, opacity 0.3s ease;
}

.arena-card-model.is-hidden {
    opacity: 0;
    pointer-events: none;
    width: 0;
    min-width: 0;
    padding: 0;
    margin: 0;
    /* 保留占位但不可见，layout 不变（用 opacity + width 0 彻底隐藏）*/
}

.arena-card-model.is-revealed {
    color: var(--accent-sunset);
    animation: arenaRevealFlash 1.2s ease;
}

@keyframes arenaRevealFlash {
    0%   { color: var(--body); opacity: 0.4; }
    20%  { color: var(--accent-sunset); opacity: 1; }
    100% { color: var(--accent-sunset); opacity: 1; }
}

.arena-card-slot {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 1.4px;
    padding: 3px 8px;
    background: var(--accent-midnight);
    border: 1px solid var(--accent-dusk);
    color: var(--accent-twilight);
    border-radius: var(--r-pill);
    font-weight: 600;
}

.arena-card-status {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--body-mid);
}

.arena-card-status.is-streaming { color: var(--accent-twilight); }
.arena-card-status.is-done { color: var(--accent-sunset); }
.arena-card-status.is-error { color: #ff7b72; }

.arena-card-body {
    flex: 1;
    padding: 14px;
    overflow-y: auto;
    font-size: 14px;
    line-height: 1.6;
    color: var(--ink);
    word-break: break-word;
}

.arena-card-body.typing::after {
    content: '▍';
    color: var(--accent-sunset);
    animation: arenaBlink 1s steps(1) infinite;
    margin-left: 2px;
}

@keyframes arenaBlink { 50% { opacity: 0; } }

.arena-card-body p { margin-bottom: 10px; }
.arena-card-body p:last-child { margin-bottom: 0; }
.arena-card-body code {
    background: var(--canvas-mid);
    padding: 1px 6px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 12px;
}
.arena-card-body pre {
    background: var(--canvas-mid);
    padding: 10px 12px;
    border-radius: var(--r-sm);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 12px;
    line-height: 1.5;
    margin: 8px 0;
    position: relative;
}
.arena-card-body pre code { background: none; padding: 0; }
.arena-card-body pre .code-copy {
    position: absolute;
    top: 6px;
    right: 6px;
    padding: 3px 8px;
    background: var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: 4px;
    color: var(--body);
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.4px;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.15s, background 0.15s, color 0.15s;
    user-select: none;
}
.arena-card-body pre:hover .code-copy,
.arena-card-body pre .code-copy:focus {
    opacity: 1;
}
.arena-card-body pre .code-copy:hover {
    background: var(--canvas-soft);
    color: var(--accent-sunset);
}

.arena-card-body .arena-card-empty {
    color: var(--body-mid);
    font-style: italic;
    font-size: 13px;
}

.arena-card-body .arena-card-error {
    color: #ff7b72;
    font-size: 13px;
}

.arena-card-footer {
    padding: 10px 14px;
    border-top: 1px solid var(--hairline);
    background: var(--canvas-soft);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.arena-card-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.6px;
    text-transform: uppercase;
    color: var(--body-mid);
}

.arena-card-meta-cost { color: var(--accent-sunset); }

/* ============ 评分区 ============ */
.arena-stars {
    display: flex;
    gap: 4px;
    align-items: center;
}

.arena-star {
    font-size: 22px;
    line-height: 1;
    cursor: pointer;
    color: var(--canvas-mid);
    transition: color 0.1s, transform 0.05s;
    user-select: none;
}

.arena-star:hover { color: var(--accent-sunset); }
.arena-star.active { color: var(--accent-sunset); }
.arena-star:active { transform: scale(0.9); }
.arena-star.display { cursor: default; }
.arena-star.hover { color: var(--accent-sunset); }

.arena-stars-interactive .arena-star {
    cursor: pointer;
    user-select: none;
    padding: 0 2px;
}

.arena-vote-display {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.arena-vote-display-row {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.arena-vote-hint {
    font-size: 11px;
    color: var(--body-mid);
    font-family: var(--font-mono);
    letter-spacing: 0.4px;
}

.arena-vote-label {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.6px;
    text-transform: uppercase;
    color: var(--body-mid);
    margin-bottom: 4px;
}

.arena-comment-input {
    width: 100%;
    padding: 6px 8px;
    background: var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    color: var(--ink);
    font-size: 12px;
    line-height: 1.5;
    resize: vertical;
    min-height: 28px;
    font-family: inherit;
    transition: border-color 0.15s;
}

.arena-comment-input:focus {
    outline: none;
    border-color: var(--canvas-mid);
}

.arena-comment-input::placeholder { color: var(--body-mid); }

/* ============ AI 评判区 ============ */
.arena-judge-extra {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--accent-sunset);
    letter-spacing: 0.4px;
    text-transform: none;
}

.arena-judge-info {
    margin-top: 4px;
    font-size: 11px;
    color: var(--body-mid);
    line-height: 1.4;
}

.arena-judge-info.has-cost { color: var(--accent-sunset); }

.arena-judge-status {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 0;
}

.arena-judge-status .dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--canvas-mid);
    flex-shrink: 0;
}

.arena-judge-status .dot.is-loading {
    background: var(--accent-twilight);
    animation: judgePulse 1.2s ease-in-out infinite;
}

.arena-judge-status .dot.is-done { background: var(--accent-sunset); }
.arena-judge-status .dot.is-error { background: #ff7b72; }

@keyframes judgePulse {
    0%, 100% { opacity: 0.4; transform: scale(0.8); }
    50% { opacity: 1; transform: scale(1.2); }
}

.arena-judge-result {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.arena-judge-result-row {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
}

.arena-judge-result-label {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.6px;
    text-transform: uppercase;
    color: var(--body-mid);
    flex-shrink: 0;
}

.arena-judge-reasoning {
    margin-top: 4px;
    padding: 6px 8px;
    background: var(--canvas);
    border-left: 2px solid var(--accent-dusk);
    border-radius: 4px;
    font-size: 12px;
    line-height: 1.5;
    color: var(--body);
    font-style: italic;
    display: none;
}

.arena-judge-reasoning.show { display: block; }

.arena-judge-reasoning-toggle {
    font-size: 11px;
    color: var(--body-mid);
    cursor: pointer;
    user-select: none;
    margin-top: 2px;
    text-decoration: underline;
    text-decoration-color: var(--canvas-mid);
    text-underline-offset: 2px;
}

.arena-judge-reasoning-toggle:hover { color: var(--accent-twilight); }

.arena-final-actions .primary-btn.judge-btn {
    background: var(--accent-dusk);
}

.arena-final-actions .primary-btn.judge-btn:disabled {
    background: var(--canvas-mid);
}

/* ============ 完成后的操作 ============ */
.arena-final-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin-top: 24px;
    padding: 20px;
}

.arena-final-actions .primary-btn:disabled {
    background: var(--canvas-mid);
    color: var(--body-mid);
    cursor: not-allowed;
}

.arena-final-actions .primary-btn {
    padding: 10px 24px;
    background: var(--accent-sunset);
    color: var(--on-primary);
    border: none;
    border-radius: var(--r-sm);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: opacity 0.15s;
}

.arena-final-actions .primary-btn:hover:not(:disabled) { opacity: 0.9; }

.arena-final-actions .ghost-btn {
    padding: 10px 24px;
    background: transparent;
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    color: var(--body);
    font-size: 14px;
    cursor: pointer;
    transition: border-color 0.15s, color 0.15s;
}

.arena-final-actions .ghost-btn:hover {
    border-color: var(--canvas-mid);
    color: var(--ink);
}

/* ============ 历史列表 ============ */
.arena-history-list { display: flex; flex-direction: column; gap: 12px; }

.arena-history-empty {
    text-align: center;
    padding: 60px 20px;
    color: var(--body-mid);
    font-size: 13px;
}

.arena-history-card {
    background: var(--canvas-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-sm);
    padding: 16px 20px;
    transition: border-color 0.15s;
    cursor: pointer;
}

.arena-history-card:hover { border-color: var(--canvas-mid); }

.arena-history-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 8px;
    gap: 12px;
}

.arena-history-card-content {
    font-size: 14px;
    color: var(--ink);
    line-height: 1.5;
    flex: 1;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
}

.arena-history-card-time {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--body-mid);
    white-space: nowrap;
}

.arena-history-card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 8px;
    margin-top: 8px;
    padding-top: 8px;
    border-top: 1px dashed var(--hairline);
}

.arena-history-card-models {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
}

.arena-history-model-tag {
    font-family: var(--font-mono);
    font-size: 10px;
    padding: 2px 8px;
    background: var(--canvas-soft);
    border: 1px solid var(--hairline);
    border-radius: var(--r-pill);
    color: var(--body);
    letter-spacing: 0.4px;
}

.arena-history-model-count {
    color: var(--accent-twilight);
    border-color: var(--accent-dusk);
    background: var(--accent-midnight);
}

.arena-history-card-cost {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--accent-sunset);
    letter-spacing: 0.4px;
}

.arena-history-card-status {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 1px;
    text-transform: uppercase;
    padding: 2px 6px;
    border-radius: var(--r-sm);
}

.arena-history-card-status.done { background: rgba(0, 200, 100, 0.1); color: #4ade80; }
.arena-history-card-status.partial { background: rgba(255, 167, 38, 0.1); color: #fbbf24; }
.arena-history-card-status.failed { background: rgba(255, 123, 114, 0.1); color: #ff7b72; }
.arena-history-card-status.streaming { background: rgba(124, 58, 237, 0.1); color: var(--accent-twilight); }

.arena-history-card-anon {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--body-mid);
    letter-spacing: 0.6px;
    text-transform: uppercase;
}

/* ============ primary-btn 全局样式兼容 ============ */
.primary-btn {
    cursor: pointer;
}