:root {
    --primary: #007AFF;
    --primary-hover: #0062CC;
    --bg-app: #F5F5F7;
    --bg-sidebar: #FFFFFF;
    --bg-card: #FFFFFF;
    --border: #E5E5E5;
    --text-main: #1D1D1F;
    --text-sec: #86868B;
    --radius-l: 16px;
    --radius-m: 10px;
    --radius-s: 6px;
    --shadow-s: 0 2px 8px rgba(0,0,0,0.04);
    --shadow-m: 0 4px 16px rgba(0,0,0,0.08);
}

* { box-sizing: border-box; outline: none; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", sans-serif;
    background-color: var(--bg-app);
    color: var(--text-main);
    height: 100vh;
    overflow: hidden;
}

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

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.1);
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background: rgba(0, 0, 0, 0.2);
}

/* --- Sidebar --- */
.sidebar {
    width: 320px;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    z-index: 10;
    overflow: hidden;
}

.sidebar-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
}

.sidebar-header h1 {
    font-size: 20px;
    font-weight: 700;
    margin: 0;
    letter-spacing: -0.5px;
}

.sidebar-header p {
    font-size: 12px;
    color: var(--text-sec);
    margin: 4px 0 0 0;
}

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

.control-section {
    margin-bottom: 32px;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.section-header h3 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-main);
    margin: 0;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.step-badge {
    font-size: 10px;
    background: #EEF2FF;
    color: var(--primary);
    padding: 2px 8px;
    border-radius: 10px;
    font-weight: 600;
}

/* Background Selector */
.category-tabs {
    display: flex;
    gap: 4px;
    background: #F2F2F7;
    padding: 3px;
    border-radius: 8px;
    margin-bottom: 12px;
}

.cat-btn {
    flex: 1;
    border: none;
    background: transparent;
    padding: 6px;
    font-size: 12px;
    font-weight: 500;
    border-radius: 6px;
    color: var(--text-sec);
    cursor: pointer;
    transition: all 0.2s;
    white-space: nowrap;
}

.cat-btn.active {
    background: #fff;
    color: #000;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.background-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    height: 180px;
    overflow-y: auto;
    padding: 4px;
}

.background-thumb {
    width: 100%;
    aspect-ratio: 1;
    border-radius: 8px;
    cursor: pointer;
    border: 2px solid transparent;
    overflow: hidden;
    position: relative;
    background: #eee;
}

.background-thumb canvas {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
}

.background-thumb.active {
    border-color: var(--primary);
}

.background-thumb:hover {
    transform: scale(1.02);
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

/* Content Type Tabs */
.content-type-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
}

.type-btn {
    flex: 1;
    padding: 8px 0;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 13px;
    color: var(--text-main);
    cursor: pointer;
}

.type-btn.active {
    border-color: var(--primary);
    background: #F0F7FF;
    color: var(--primary);
    font-weight: 500;
}

/* Controls */
.control-group {
    margin-bottom: 16px;
}

.control-group label {
    display: block;
    font-size: 12px;
    color: var(--text-sec);
    margin-bottom: 6px;
}

.control-row {
    display: flex;
    gap: 12px;
}

.control-group.half {
    flex: 1;
}

.modern-input, .modern-select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 13px;
    background: #fff;
    transition: border 0.2s;
}

.modern-input:focus, .modern-select:focus {
    border-color: var(--primary);
}

/* Segmented Control */
.segmented-control {
    display: flex;
    background: #F2F2F7;
    padding: 2px;
    border-radius: 8px;
}

.segmented-control input { display: none; }

.segmented-control label {
    flex: 1;
    text-align: center;
    padding: 6px 0;
    font-size: 12px;
    border-radius: 6px;
    cursor: pointer;
    margin: 0 !important;
    color: var(--text-sec);
}

.segmented-control input:checked + label {
    background: #fff;
    color: #000;
    box-shadow: 0 1px 2px rgba(0,0,0,0.1);
    font-weight: 500;
}

/* Upload Box */
.upload-box {
    border: 2px dashed var(--border);
    border-radius: 12px;
    padding: 24px;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    background: #FAFAFA;
    margin-bottom: 16px;
}

.upload-box:hover {
    border-color: var(--primary);
    background: #F0F7FF;
}

.upload-icon {
    color: var(--primary);
    margin-bottom: 8px;
}

.upload-box p {
    font-size: 12px;
    color: var(--text-sec);
    margin: 0;
}

/* Sliders & Color */
.slider-group {
    margin-bottom: 12px;
}
.slider-group label {
    display: flex;
    justify-content: space-between;
    font-size: 11px;
    color: var(--text-sec);
    margin-bottom: 4px;
}
input[type=range] {
    width: 100%;
    height: 4px;
    background: #E5E5E5;
    border-radius: 2px;
    -webkit-appearance: none;
}
input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    background: #fff;
    border: 1px solid var(--border);
    box-shadow: 0 1px 3px rgba(0,0,0,0.2);
    border-radius: 50%;
    cursor: pointer;
    margin-top: -6px;
}
input[type=range]::-webkit-slider-runnable-track {
    height: 4px;
    background: #ddd;
    border-radius: 2px;
}

.color-picker-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    gap: 8px;
}
input[type=color] {
    width: 32px;
    height: 32px;
    border: none;
    padding: 0;
    background: none;
    cursor: pointer;
}
.color-value {
    font-size: 12px;
    color: var(--text-sec);
    font-family: monospace;
}

/* Toggle Switch */
.toggle-label {
    display: flex !important;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
}
.toggle-label input { display: none; }
.toggle-switch {
    width: 36px;
    height: 20px;
    background: #E5E5E5;
    border-radius: 12px;
    position: relative;
    transition: 0.3s;
}
.toggle-switch::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 16px;
    height: 16px;
    background: #fff;
    border-radius: 50%;
    transition: 0.3s;
    box-shadow: 0 1px 2px rgba(0,0,0,0.2);
}
.toggle-label input:checked + .toggle-switch {
    background: var(--primary);
}
.toggle-label input:checked + .toggle-switch::after {
    transform: translateX(16px);
}

/* Sub Controls */
.sub-controls {
    background: #F5F5F7;
    padding: 12px;
    border-radius: 8px;
    margin-top: 12px;
}

/* Footer */
.sidebar-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #F9F9F9;
}
.author-info {
    font-size: 12px;
    color: var(--text-sec);
}
.author-link {
    color: var(--text-main);
    text-decoration: none;
    font-weight: 600;
    margin-left: 4px;
}
.author-link:hover {
    color: var(--primary);
}
.icon-btn {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-sec);
    padding: 4px;
    border-radius: 4px;
}
.icon-btn:hover {
    background: #eee;
    color: var(--text-main);
}

/* --- Main View --- */
.main-view {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: #F5F5F7;
    overflow: hidden;
}

.top-bar {
    height: 64px;
    background: #fff;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 32px;
    flex-shrink: 0;
}

.breadcrumbs {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-main);
}

.download-btn {
    background: var(--primary);
    color: #fff;
    border: none;
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    transition: 0.2s;
}
.download-btn:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0,122,255,0.2);
}

.content-scroller {
    flex: 1;
    overflow: hidden; /* 使用 hidden 防止双重滚动，让内部区域自适应 */
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 24px;
    max-width: 1400px; /* 稍微放宽一点 */
    margin: 0 auto;
    width: 100%;
}

.preview-card {
    background: #fff;
    border-radius: var(--radius-l);
    box-shadow: var(--shadow-s);
    overflow: hidden;
    border: 1px solid rgba(0,0,0,0.02);
    display: flex;
    flex-direction: column;
}

/* New Layout */
.preview-top-section {
    display: flex;
    gap: 24px;
    flex: 1; /* 占据剩余垂直空间 */
    min-height: 0; /* 允许子元素收缩 */
}

.main-card {
    flex: 1;
    min-width: 0;
    height: 100%;
}

.size-card {
    width: 300px;
    flex-shrink: 0;
    height: 100%;
}

.canvas-wrapper {
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    background: 
        linear-gradient(45deg, #f9f9f9 25%, transparent 25%),
        linear-gradient(-45deg, #f9f9f9 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #f9f9f9 75%),
        linear-gradient(-45deg, transparent 75%, #f9f9f9 75%);
    background-size: 20px 20px;
    background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
    flex: 1;
    overflow: hidden; /* 防止内容溢出 */
}

#master-canvas {
    max-width: 100%; 
    max-height: 100%; /* 自适应高度，不超过容器 */
    width: auto;
    height: auto;
    border-radius: 22.37%;
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
    object-fit: contain;
}

.size-grid {
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    align-items: center;
    overflow-y: auto; /* 允许列表滚动 */
    flex: 1; /* 撑满剩余高度 */
    max-height: none;
}

.dock-card {
    flex-shrink: 0; /* 防止 Dock 被压缩 */
}

.size-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.size-item canvas {
    border-radius: 22.37%;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    border: 1px solid rgba(0,0,0,0.05);
}

.size-item span {
    font-size: 11px;
    color: var(--text-sec);
}

/* macOS Dock */
.macos-desktop {
    height: 120px; /* Reduced from 200px */
    background: url('https://images.unsplash.com/photo-1621193793262-40a815377497?q=80&w=1000&auto=format&fit=crop') center/cover;
    position: relative;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding-bottom: 16px;
}

.dock-container {
    height: 64px;
}

.dock-glass {
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 16px;
    padding: 6px 12px;
    display: flex;
    gap: 8px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.2);
}

.dock-item {
    width: 48px;
    height: 48px;
    position: relative;
    transition: transform 0.2s cubic-bezier(0.2, 0, 0.2, 1);
}

.dock-item:hover {
    transform: scale(1.2) translateY(-10px);
    margin: 0 8px;
}

.app-icon, #dock-icon-img {
    width: 100%;
    height: 100%;
    border-radius: 12px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

#dock-icon-img {
    border-radius: 22.37%; /* Perfect Apple shape */
}

.system-1 { background: linear-gradient(to bottom, #5A9BFF, #0055FF); }
.system-2 { background: linear-gradient(to bottom, #FFCC00, #FF9500); }
.system-3 { background: linear-gradient(to bottom, #34C759, #30B400); }
.system-4 { background: linear-gradient(to bottom, #AF52DE, #5856D6); }

.dock-dot {
    width: 4px;
    height: 4px;
    background: rgba(255,255,255,0.8);
    border-radius: 50%;
    position: absolute;
    bottom: -6px;
    left: 50%;
    transform: translateX(-50%);
}

@media (max-width: 1024px) {
    .content-scroller { overflow-y: auto; display: block; }
    .preview-top-section { flex-direction: column; height: auto; flex: none; }
    .main-card, .size-card { height: auto; width: 100%; }
    .canvas-wrapper { height: 400px; }
    .size-grid { flex-direction: row; flex-wrap: wrap; justify-content: center; max-height: none; overflow-y: visible; }
    #master-canvas { max-height: 100%; }
}

/* Icon Selector Styles */
.icon-categories {
    overflow-x: auto;
    padding-bottom: 4px; /* For scrollbar space */
}

.icon-grid-wrapper {
    height: 240px;
    overflow-y: auto;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: #fff;
    padding: 8px;
    margin-bottom: 16px;
}

.icon-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 8px;
}

.icon-item {
    aspect-ratio: 1;
    border-radius: 6px;
    border: 1px solid transparent;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    background: #FAFAFA;
    padding: 4px;
}

.icon-item:hover {
    background: #F0F7FF;
    transform: scale(1.05);
}

.icon-item.active {
    background: #F0F7FF;
    border-color: var(--primary);
    color: var(--primary);
}

.icon-item svg {
    width: 24px;
    height: 24px;
    stroke: currentColor;
    fill: none;
    stroke-width: 2;
    margin-bottom: 4px;
}

.icon-item span {
    font-size: 9px;
    color: var(--text-sec);
    text-align: center;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    width: 100%;
}

.icon-item.active span {
    color: var(--primary);
}