:root {
    --bg-primary: #0d1117;
    --bg-card: #161b22;
    --bg-input: #0d1117;
    --border: #30363d;
    --border-focus: #58a6ff;
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --text-muted: #484f58;
    --accent: #58a6ff;
    --accent-green: #3fb950;
    --accent-red: #f85149;
    --accent-yellow: #d29922;
    --accent-purple: #bc8cff;
    --shadow: 0 2px 12px rgba(0,0,0,.4);
    --radius: 10px;
}

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

body {
    font-family: 'Segoe UI', -apple-system, system-ui, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    min-height: 100vh;
}

/* ─── 顶部导航 ─── */
.header {
    background: linear-gradient(135deg, #161b22 0%, #1c2333 100%);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px;
    display: flex;
    align-items: center;
    gap: 16px;
}
.header h1 {
    font-size: 20px;
    font-weight: 700;
    background: linear-gradient(90deg, #58a6ff, #bc8cff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.header .subtitle { color: var(--text-secondary); font-size: 13px; }

.connection-bar {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 10px;
}

/* ─── 按钮 ─── */
.btn {
    padding: 7px 16px;
    border: 1px solid var(--border);
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    transition: all .15s;
    background: var(--bg-card);
    color: var(--text-primary);
}
.btn:hover { border-color: var(--border-focus); }
.btn:disabled { opacity: .4; cursor: not-allowed; }
.btn-primary { background: #238636; border-color: #2ea043; color: #fff; }
.btn-primary:hover { background: #2ea043; }
.btn-danger { background: #da3633; border-color: #f85149; color: #fff; }
.btn-danger:hover { background: #f85149; }
.btn-accent { background: #1f6feb; border-color: #388bfd; color: #fff; }
.btn-accent:hover { background: #388bfd; }

/* ─── 状态徽章 ─── */
.badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}
.badge::before {
    content: '';
    width: 8px;
    height: 8px;
    border-radius: 50%;
}
.badge-off { background: #f8514933; color: #f85149; }
.badge-off::before { background: #f85149; }
.badge-on { background: #3fb95033; color: #3fb950; }
.badge-on::before { background: #3fb950; animation: pulse 2s infinite; }

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: .4; }
}

/* ─── 主布局 ─── */
.main {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    padding: 16px 24px;
    max-width: 1200px;
    margin: 0 auto;
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px;
    box-shadow: var(--shadow);
}
.card-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: .5px;
}

/* ─── 图片上传区 ─── */
.upload-zone {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 40px;
    text-align: center;
    cursor: pointer;
    transition: all .2s;
    color: var(--text-secondary);
}
.upload-zone:hover, .upload-zone.drag-over {
    border-color: var(--accent);
    background: #58a6ff10;
}
.upload-zone .icon { font-size: 36px; margin-bottom: 8px; }
.upload-zone input { display: none; }

/* ─── 预览 ─── */
.preview-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-top: 12px;
}
.preview-box {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 8px;
    text-align: center;
}
.preview-box canvas {
    max-width: 100%;
    image-rendering: pixelated;
    border-radius: 4px;
}
.preview-box .label {
    font-size: 11px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* ─── 参数 ─── */
.param-grid {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 8px 12px;
    align-items: center;
}
.param-grid label { font-size: 13px; color: var(--text-secondary); }
.param-grid input, .param-grid select {
    padding: 5px 10px;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-primary);
    font-size: 13px;
}
.param-grid input:focus { border-color: var(--border-focus); outline: none; }
.param-grid input[type="range"] { padding: 0; }

/* ─── 调色板 ─── */
.palette {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-top: 8px;
}
.palette-swatch {
    width: 24px;
    height: 24px;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all .15s;
}
.palette-swatch:hover { transform: scale(1.2); }
.palette-swatch.active { border-color: #fff; box-shadow: 0 0 8px rgba(255,255,255,.5); }

.palette-info {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 6px;
}

/* ─── 进度条 ─── */
.progress-container { margin: 12px 0; }
.progress-bar {
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
}
.progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, #58a6ff, #bc8cff);
    border-radius: 3px;
    transition: width .3s;
    width: 0%;
}
.progress-text {
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* ─── 控制按钮组 ─── */
.control-row {
    display: flex;
    gap: 8px;
    margin-top: 12px;
    flex-wrap: wrap;
}

/* ─── 日志 ─── */
.log-panel {
    grid-column: 1 / -1;
}
.log-box {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px;
    font-family: 'Cascadia Code', 'Fira Code', monospace;
    font-size: 12px;
    line-height: 1.6;
    max-height: 220px;
    overflow-y: auto;
    white-space: pre-wrap;
    word-break: break-all;
}
.log-box .info { color: var(--accent); }
.log-box .ok { color: var(--accent-green); }
.log-box .warn { color: var(--accent-yellow); }
.log-box .err { color: var(--accent-red); }

/* ─── 模态框（换色提示） ─── */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.7);
    z-index: 100;
    align-items: center;
    justify-content: center;
}
.modal-overlay.show { display: flex; }
.modal {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 32px;
    max-width: 400px;
    text-align: center;
    box-shadow: 0 8px 32px rgba(0,0,0,.6);
}
.modal h3 { font-size: 18px; margin-bottom: 16px; }
.modal .color-display {
    width: 80px;
    height: 80px;
    border-radius: 12px;
    margin: 16px auto;
    border: 3px solid var(--border);
}
.modal .color-hex {
    font-family: monospace;
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 16px;
}
.modal .color-rgb {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 20px;
}
.modal .modal-btns {
    display: flex;
    gap: 12px;
    justify-content: center;
}

/* ─── 统计信息 ─── */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 8px;
    margin-top: 8px;
}
.stat-item {
    background: var(--bg-input);
    border-radius: 8px;
    padding: 10px;
    text-align: center;
}
.stat-value {
    font-size: 20px;
    font-weight: 700;
    color: var(--accent);
}
.stat-label {
    font-size: 11px;
    color: var(--text-muted);
    margin-top: 2px;
}