:root {
    /* Light Mode Variables */
    --bg-page: #f1f5f9;
    --bg-card: #ffffff;
    --bg-glass: rgba(255, 255, 255, 0.95);
    --bg-hover: #f8fafc;
    --bg-input: #ffffff;
    --bg-input-border: #cbd5e1;
    
    --text-main: #1e293b;
    --text-sub: #64748b;
    --text-inverse: #ffffff;
    
    --border-color: #e2e8f0;
    --border-dashed: #cbd5e1;
    
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --accent-light: #eff6ff;
    
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --radius: 12px;

    --landing-gradient: radial-gradient(circle at center, #ffffff 0%, #f8fafc 100%);
    --canvas-gradient: radial-gradient(circle at center, #f8fafc 0%, #cbd5e1 100%);
}

/* Dark Mode Variables */
body.dark-mode {
    --bg-page: #0f172a;
    --bg-card: #1e293b;
    --bg-glass: rgba(30, 41, 59, 0.95);
    --bg-hover: #334155;
    --bg-input: #1e293b;
    --bg-input-border: #475569;
    
    --text-main: #f1f5f9;
    --text-sub: #94a3b8;
    --text-inverse: #0f172a;
    
    --border-color: #334155;
    --border-dashed: #475569;
    
    --accent: #60a5fa;
    --accent-hover: #3b82f6;
    --accent-light: rgba(59, 130, 246, 0.2);
    
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);

    --landing-gradient: radial-gradient(circle at center, #1e293b 0%, #0f172a 100%);
    --canvas-gradient: radial-gradient(circle at center, #1e293b 0%, #0f172a 100%);
}

body { margin: 0; overflow: hidden; font-family: 'Inter', sans-serif; background: var(--bg-page); color: var(--text-main); transition: background 0.3s, color 0.3s; }

/* 引导页样式 */
#landing-page {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    z-index: 1000; background: radial-gradient(circle at center, #ffffff 0%, #f1f5f9 100%);
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    transition: transform 0.6s cubic-bezier(0.86, 0, 0.07, 1), opacity 0.4s ease;
}
#landing-page.hidden { transform: translateY(-100%); opacity: 0; pointer-events: none; }

.landing-content { max-width: 900px; text-align: center; padding: 40px; }
.landing-logo { font-size: 48px; font-weight: 800; margin-bottom: 12px; background: #2563eb; -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.landing-subtitle { font-size: 18px; color: var(--text-sub); margin-bottom: 40px; font-weight: 500;}

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: 48px; }
.feature-card { background: white; padding: 28px; border-radius: 20px; border: 1px solid var(--glass-border); box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05); transition: transform 0.2s; }
.feature-card:hover { transform: translateY(-4px); }
.feature-card i { font-size: 28px; color: var(--accent); margin-bottom: 16px; }
.feature-card h3 { margin: 0 0 8px 0; font-size: 17px; font-weight: 600; }
.feature-card p { margin: 0; font-size: 14px; color: var(--text-sub); line-height: 1.6; }

.upload-zone {
    border: 2px dashed #cbd5e1; border-radius: 24px; padding: 48px;
    background: #f8fafc; cursor: pointer; transition: all 0.3s;
    display: flex; flex-direction: column; align-items: center; gap: 16px;
}
.upload-zone:hover { background: #eff6ff; border-color: var(--accent); }
.upload-zone i { font-size: 40px; color: #94a3b8; transition: color 0.3s;}
.upload-zone:hover i { color: var(--accent); }


.landing-actions { display: flex; gap: 16px; margin-top: 24px; justify-content: center; }
.btn-outline {
    padding: 12px 24px; border: 1px solid var(--border-color); background: var(--bg-card); border-radius: 10px;
    color: var(--text-main); font-weight: 600; cursor: pointer; transition: all 0.2s;
    display: flex; align-items: center; gap: 8px;
}
.btn-outline:hover { background: var(--bg-hover); border-color: var(--text-sub); }

/* 主界面 */
#canvas-container { position: absolute; top: 0; left: 0; width: 100%; height: 100%; z-index: 1; background: var(--canvas-gradient); transition: background 0.3s; }

.brand-logo {
    position: absolute;
    left: 24px;
    top: 24px;
    z-index: 100;           
    padding: 12px 24px;      
    width: 150px;     
}

#sidebar {
    position: absolute; right: 24px; top: 24px; bottom: 24px; width: 360px;
    background: var(--bg-glass); backdrop-filter: blur(20px);
    border: 1px solid var(--border-color); border-radius: 20px;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1); z-index: 100; 
    display: flex; flex-direction: column; overflow: hidden;
    transition: background 0.3s, border-color 0.3s;
}

.sidebar-header {
    padding: 20px 24px; border-bottom: 1px solid var(--border-color);
    display: flex; justify-content: space-between; align-items: center; background: rgba(var(--bg-card), 0.5);
}
.sidebar-header h2 { margin: 0; font-size: 16px; font-weight: 700; color: var(--text-main); }

.sidebar-scroll { flex: 1; overflow-y: auto; padding: 24px; }

.section-title {
    font-size: 12px; font-weight: 700; color: var(--text-sub); 
    text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 12px;
    display: flex; align-items: center; justify-content: space-between; margin-top: 24px;
}
.section-title:first-child { margin-top: 0; }

/* 顶部操作按钮组 */
.action-group {
    display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 20px;
}
.action-btn {
    padding: 12px; border: 1px solid var(--border-color); border-radius: 10px; background: var(--bg-card);
    color: var(--text-main); font-size: 13px; font-weight: 600; cursor: pointer;
    display: flex; align-items: center; justify-content: center; gap: 8px; transition: all 0.2s;
}
.action-btn:hover { background: var(--bg-hover); border-color: var(--accent); color: var(--accent); }
.action-btn i { font-size: 14px; }

/* 打印机选择 */
.form-select {
    width: 100%; padding: 12px; border-radius: 10px; border: 1px solid var(--border-color);
    background: var(--bg-card); font-size: 14px; color: var(--text-main); outline: none; cursor: pointer;
}
.form-select:focus { border-color: var(--accent); }

/* 材质选择卡片 */
.material-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 8px; }
.material-option {
    position: relative;
    background: var(--bg-card); border: 2px solid transparent; border-radius: 12px;
    padding: 12px; cursor: pointer; transition: all 0.2s;
    display: flex; flex-direction: column; align-items: flex-start; gap: 6px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.05);
}
.material-option:hover { transform: translateY(-2px); border-color: var(--border-color); }
.material-option.active { border-color: var(--accent); background: var(--accent-light); }

.mat-header { display: flex; align-items: center; gap: 8px; width: 100%; }
.mat-color-dot { 
    width: 24px; height: 24px; border-radius: 50%; border: 1px solid rgba(0,0,0,0.1); 
    flex-shrink: 0; background-size: cover; background-position: center;
}
.mat-name { font-size: 13px; font-weight: 600; color: var(--text-main); }
.mat-desc { font-size: 11px; color: var(--text-sub); line-height: 1.3; }

/* 材质预览悬停图 */
.preview-popover {
    position: absolute; top: -110px; left: 50%; transform: translateX(-50%);
    width: 120px; height: 100px; background: var(--bg-card); border-radius: 10px;
    box-shadow: 0 10px 15px -3px rgba(0,0,0,0.1); border: 1px solid var(--border-color);
    display: none; z-index: 200; overflow: hidden; pointer-events: none;
}
.preview-popover img { width: 100%; height: 100%; object-fit: cover; }
.material-option:hover .preview-popover { display: block; animation: fadeIn 0.2s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateX(-50%) translateY(10px); } to { opacity: 1; transform: translateX(-50%) translateY(0); } }

/* 视角控制按钮 (位置: 右上角) */
.view-controls {
    position: absolute; 
    top: 30px; 
    right: 420px; /* 侧边栏宽 360 + margin 24 + 间距 16 = 400 */
    z-index: 100;
    display: flex; 
    flex-direction: column; 
    gap: 16px; /* 增加间距以容纳文字 */
}
.control-item { 
    position: relative; 
    display: flex;
    flex-direction: column;
    align-items: center;
}

.icon-btn {
    width: 44px; height: 44px; border-radius: 50%; background: var(--bg-card);
    border: 1px solid var(--border-color); color: var(--text-sub); font-size: 16px;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; box-shadow: var(--shadow); transition: all 0.2s;
}
.icon-btn:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1); }

/* 图标下方的功能文字标签 */
.control-label {
    margin-top: 6px;
    font-size: 11px;
    font-weight: 600;
    color: var(--text-sub);
    text-shadow: 0 1px 0 rgba(255,255,255,0.8);
    pointer-events: none;
    white-space: nowrap;
}
body.dark-mode .control-label {
    text-shadow: 0 1px 0 rgba(0,0,0,0.8);
}

/* 隐藏原来的tooltip */
.tooltip { display: none; }

/* 客服二维码弹窗 (位置: 向左弹出) */
.qr-popover {
    position: absolute; right: 55px; top: 0; left: auto; bottom: auto;
    background: white; padding: 12px; border-radius: 12px;
    box-shadow: 0 10px 25px -5px rgba(0,0,0,0.15);
    border: 1px solid #e2e8f0;
    display: none; flex-direction: column; align-items: center;
    width: 140px; z-index: 200;
    /* 强制亮色背景以保证二维码可读 */
    color: #1e293b; 
}
.qr-popover img { width: 100%; height: auto; border-radius: 4px; }
.qr-text { margin-top: 8px; font-size: 12px; font-weight: 600; }

.control-item:hover .qr-popover { display: flex; animation: fadeIn 0.2s ease; }

/* 激活状态的按钮样式 */
.icon-btn.active {
    color: var(--accent);
    border-color: var(--accent);
    background: var(--accent-light);
    box-shadow: inset 0 2px 4px 0 rgba(0, 0, 0, 0.06);
}

/* 尺寸滑块 */
.size-control-container {
    background: var(--bg-card); padding: 16px; border-radius: 12px; border: 1px solid var(--border-color);
}
.size-info-row { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.size-val { font-size: 18px; font-weight: 700; color: var(--text-main); }
.size-tag { 
    font-size: 11px; padding: 4px 8px; border-radius: 4px; font-weight: 600;
    background: var(--bg-page); color: var(--text-sub); text-transform: uppercase;
}
.size-tag.active { background: var(--accent-light); color: var(--accent); }

input[type="range"] {
    width: 100%; height: 6px; -webkit-appearance: none; background: var(--border-color); border-radius: 3px; outline: none; margin: 10px 0;
}
input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none; width: 20px; height: 20px; background: var(--bg-card); border-radius: 50%; 
    box-shadow: 0 2px 4px rgba(0,0,0,0.1); border: 2px solid var(--accent); cursor: pointer; transition: transform 0.1s;
}
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.1); }

.cost-estimate {
    font-size: 12px; color: var(--text-sub); margin-top: 8px; display: flex; gap: 6px; align-items: center;
}

/* 底部 */
.sidebar-footer {
    padding: 20px 24px; background: var(--bg-card); border-top: 1px solid var(--border-color);
}

.total-price-row {
    display: flex; justify-content: space-between; align-items: flex-end; margin-bottom: 16px;
}
.total-label { font-size: 13px; color: var(--text-sub); }
.total-amount { font-size: 28px; font-weight: 800; color: var(--text-main); line-height: 1; }
.total-unit { font-size: 16px; font-weight: 600; color: var(--text-main); margin-right: 2px; }

.btn-primary {
    width: 100%; padding: 14px; background: var(--accent); color: white;
    border: none; border-radius: 10px; font-size: 15px; font-weight: 600;
    cursor: pointer; transition: background 0.2s; display: flex; justify-content: center; align-items: center; gap: 8px;
}
.btn-primary:hover { background: var(--accent-hover); }

/* 模型库弹窗 & 订单弹窗 */
.modal-overlay {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.4); backdrop-filter: blur(4px); z-index: 2000;
    display: flex; align-items: center; justify-content: center;
    opacity: 0; pointer-events: none; transition: opacity 0.3s;
}
.modal-overlay.show { opacity: 1; pointer-events: auto; }

.modal-content {
    background: var(--bg-card); width: 90%; max-width: 800px; height: 80vh; max-height: 700px;
    border-radius: 16px; display: flex; flex-direction: column; overflow: hidden;
    box-shadow: 0 25px 50px -12px rgba(0,0,0,0.25); transform: scale(0.95); transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    color: var(--text-main);
}
.modal-overlay.show .modal-content { transform: scale(1); }

.modal-header { padding: 20px; border-bottom: 1px solid var(--border-color); display: flex; justify-content: space-between; align-items: center; }
.modal-header h3 { margin: 0; font-size: 18px; }
.close-btn { background: none; border: none; font-size: 20px; cursor: pointer; color: var(--text-sub); }

.modal-toolbar { padding: 16px; background: var(--bg-hover); border-bottom: 1px solid var(--border-color); display: flex; gap: 12px; }
.search-input { flex: 1; padding: 10px 16px; border-radius: 8px; border: 1px solid var(--bg-input-border); outline: none; background: var(--bg-input); color: var(--text-main); }

.modal-grid { 
    flex: 1; overflow-y: auto; padding: 24px; display: grid; 
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 20px; 
}
.lib-item {
    border: 1px solid var(--border-color); border-radius: 12px; cursor: pointer; transition: all 0.2s;
    overflow: hidden; background: var(--bg-card);
}
.lib-item:hover { transform: translateY(-4px); border-color: var(--accent); box-shadow: 0 10px 15px -3px rgba(0,0,0,0.05); }
.lib-img { height: 120px; background: var(--bg-page); display: flex; align-items: center; justify-content: center; color: var(--text-sub); font-size: 40px; }
.lib-info { padding: 12px; }
.lib-name { font-weight: 600; font-size: 14px; margin-bottom: 4px; display: block; color: var(--text-main); }
.lib-cat { font-size: 11px; color: var(--text-sub); background: var(--bg-page); padding: 2px 6px; border-radius: 4px; }

#loading {
    position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
    background: var(--bg-glass); padding: 24px 48px; border-radius: 16px; display: none; z-index: 200; 
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1); text-align: center; border: 1px solid var(--border-color); color: var(--text-main);
}

#toast {
    position: fixed; top: 40px; left: 50%; transform: translateX(-50%) translateY(-20px);
    background: #1e293b; color: white; padding: 10px 20px; border-radius: 50px;
    font-size: 13px; font-weight: 500; opacity: 0; pointer-events: none; transition: all 0.3s;
    z-index: 2000; box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}
#toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }