/* ===== CSS Variables ===== */
:root {
    --color-primary: #0d9488;
    --color-primary-light: #ccfbf1;
    --color-primary-hover: #0f766e;
    --color-bg: #f5f5f5;
    --color-surface: #ffffff;
    --color-border: #e5e7eb;
    --color-text: #1f2937;
    --color-text-secondary: #6b7280;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.08);
    --radius: 12px;
    --radius-sm: 8px;
    --header-brand-height: 38px;
    --header-main-height: 72px;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
    --color-brand-bar-bg: #eef7f6;
    --color-brand-accent: #0d9488;
}

[data-theme="dark"] {
    --color-bg: #111827;
    --color-surface: #1f2937;
    --color-border: #374151;
    --color-text: #f9fafb;
    --color-text-secondary: #9ca3af;
    --color-brand-bar-bg: #0f172a;
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.3);
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

a {
    text-decoration: none;
    color: inherit;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

input, select {
    font-family: inherit;
}

/* ===== Header ===== */
.site-header {
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
}

.header-brand {
    height: var(--header-brand-height);
    background: var(--color-brand-bar-bg);
    border-bottom: 1px solid var(--color-border);
}

.header-brand-inner,
.header-main-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
}

.header-brand-inner {
    justify-content: space-between;
    gap: 12px;
}

.header-brand-start {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 0;
    flex: 1;
}

.header-main-inner {
    justify-content: center;
    gap: 12px;
}

.brand-home {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--color-brand-accent);
    font-weight: 700;
    font-size: 13px;
    flex-shrink: 0;
    transition: opacity 0.2s;
}

.brand-home:hover {
    opacity: 0.85;
}

.brand-mark {
    display: flex;
    align-items: center;
}

.brand-tagline {
    font-size: 12px;
    color: var(--color-text-secondary);
    flex-shrink: 0;
    padding-right: 4px;
    border-right: 1px solid var(--color-border);
    margin-right: 4px;
    line-height: 1;
}

.brand-tools {
    display: flex;
    align-items: center;
    gap: 6px;
    min-width: 0;
    overflow-x: auto;
    scrollbar-width: none;
}

.brand-tools::-webkit-scrollbar {
    display: none;
}

.brand-tool {
    display: inline-flex;
    align-items: center;
    height: 26px;
    padding: 0 12px;
    border-radius: 999px;
    font-size: 12px;
    white-space: nowrap;
    color: var(--color-text-secondary);
    border: 1px solid transparent;
    transition: color 0.2s, background 0.2s, border-color 0.2s;
}

.brand-tool:hover {
    color: var(--color-brand-accent);
    background: var(--color-surface);
    border-color: var(--color-border);
}

.brand-tool.is-current {
    color: var(--color-brand-accent);
    background: var(--color-surface);
    border-color: rgba(13, 148, 136, 0.35);
    font-weight: 600;
    box-shadow: var(--shadow-sm);
}

.header-main {
    height: var(--header-main-height);
    background: var(--color-surface);
}

.tool-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    transition: opacity 0.2s;
}

.tool-logo:hover {
    opacity: 0.85;
}

.tool-logo-icon {
    color: var(--color-primary);
    display: flex;
    flex-shrink: 0;
}

.tool-logo-text {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    text-align: center;
}

.tool-logo-name {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-text);
    line-height: 1.2;
}

.tool-logo-desc {
    font-size: 13px;
    color: var(--color-text-secondary);
    line-height: 1.2;
}

.header-actions {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.header-brand .icon-btn {
    width: 32px;
    height: 32px;
}

.header-brand .icon-btn:hover {
    background: var(--color-surface);
}

.icon-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-secondary);
    transition: background 0.2s, color 0.2s;
}

.icon-btn:hover {
    background: var(--color-bg);
}

/* ===== Main ===== */
.site-main {
    flex: 1;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 32px 24px 48px;
}

/* ===== Editor Section ===== */
.editor-section {
    display: flex;
    flex-direction: column;
    gap: 28px;
}

/* Preview */
.preview-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.preview-stage {
    width: 100%;
    max-width: 860px;
    height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto;
}

.preview-box {
    position: relative;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    background: #000;
    flex-shrink: 0;
}

.preview-box .canvas-container {
    width: 100% !important;
    height: 100% !important;
}

.preview-hint {
    margin-top: 12px;
    text-align: center;
    font-size: 13px;
    color: var(--color-text-secondary);
}

/* Controls */
.controls-stack {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.text-blocks-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.bg-settings-layout {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.bg-tabs {
    display: flex;
    gap: 8px;
    padding: 4px;
    background: var(--color-bg);
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
}

.bg-tab {
    flex: 1;
    padding: 8px 12px;
    border: none;
    border-radius: 6px;
    background: transparent;
    color: var(--color-text-secondary);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s, color 0.2s, box-shadow 0.2s;
    white-space: nowrap;
}

.bg-tab:hover {
    color: var(--color-text);
}

.bg-tab.is-active {
    background: var(--color-surface);
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

.bg-tab-panels {
    min-height: 120px;
}

.bg-tab-panel {
    display: none;
}

.bg-tab-panel.is-active {
    display: block;
}

.upload-btn--block {
    width: 100%;
}

.other-settings {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.field-row--between {
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

.field-row--between .field-hint {
    margin-top: 4px;
}

.platform-settings {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
}

.platform-settings .select-input.full-width {
    flex: 1;
    min-width: 280px;
}

.platform-settings .custom-size-row {
    flex: 1 1 100%;
    min-width: 200px;
}

.platform-settings #customSizeHint {
    flex: 1 1 100%;
}

.custom-size-toggle {
    display: flex;
    align-items: center;
    gap: 8px;
    flex: 1 1 100%;
    font-size: 13px;
    color: var(--color-text);
    cursor: pointer;
    user-select: none;
}

.custom-size-toggle input {
    width: 16px;
    height: 16px;
    accent-color: var(--color-primary);
    cursor: pointer;
}

.platform-settings.is-custom-active .select-input {
    opacity: 0.55;
}

.field-hint {
    font-size: 12px;
    color: var(--color-text-secondary);
    line-height: 1.5;
    margin-top: 2px;
}

.control-panel {
    background: var(--color-surface);
    border-radius: var(--radius);
    padding: 18px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    transition: border-color 0.2s, box-shadow 0.2s;
}

.panel-heading {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 4px;
}

.text-block {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 12px;
    border-radius: var(--radius-sm);
    border: 1px solid transparent;
    transition: border-color 0.2s, background 0.2s;
}

.text-block.is-active {
    border-color: var(--color-primary);
    background: var(--color-primary-light);
}

[data-theme="dark"] .text-block.is-active {
    background: rgba(13, 148, 136, 0.12);
}

.text-divider {
    height: 1px;
    background: var(--color-border);
    margin: 4px 0;
}

.field-label {
    font-size: 12px;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.field-row {
    display: flex;
    align-items: center;
    gap: 10px;
}

.field-row .slider-row {
    flex: 1;
    min-width: 0;
}

.field-row-label {
    font-size: 12px;
    color: var(--color-text-secondary);
    white-space: nowrap;
    min-width: 28px;
}

.control-panel.is-active {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 1px var(--color-primary);
}

.text-input {
    padding: 10px 12px;
    border: none;
    outline: none;
    font-size: 14px;
    background: transparent;
    color: var(--color-text);
    min-width: 0;
}

.text-input.full-width {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    width: 100%;
}

.text-input.full-width:focus {
    border-color: var(--color-primary);
}

.slider-row {
    display: flex;
    align-items: center;
    gap: 12px;
}

.range-input {
    flex: 1;
    -webkit-appearance: none;
    height: 4px;
    border-radius: 2px;
    background: var(--color-border);
    outline: none;
}

.range-input::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--color-primary);
    cursor: pointer;
    border: 2px solid var(--color-surface);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

.range-input::-moz-range-thumb {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--color-primary);
    cursor: pointer;
    border: 2px solid var(--color-surface);
}

.range-value {
    font-size: 13px;
    color: var(--color-text-secondary);
    min-width: 28px;
    text-align: right;
    font-variant-numeric: tabular-nums;
}

.panel-footer {
    display: flex;
    align-items: center;
    gap: 8px;
}

.panel-footer--stack {
    flex-direction: column;
    align-items: stretch;
}

.custom-size-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.size-input {
    flex: 1;
    min-width: 0;
    padding: 8px 10px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    background: var(--color-surface);
    color: var(--color-text);
    outline: none;
}

.size-input:focus {
    border-color: var(--color-primary);
}

.size-sep {
    color: var(--color-text-secondary);
    font-size: 14px;
    flex-shrink: 0;
}

.select-input {
    flex: 1;
    padding: 8px 10px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    background: var(--color-surface);
    color: var(--color-text);
    outline: none;
    cursor: pointer;
    min-width: 0;
}

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

.color-picker {
    width: 36px;
    height: 36px;
    padding: 2px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    background: none;
    flex-shrink: 0;
}

.magic-btn {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-secondary);
    border: 1px solid var(--color-border);
    transition: all 0.2s;
    flex-shrink: 0;
}

.magic-btn:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
    background: var(--color-primary-light);
}

.upload-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 16px;
    border: 1px dashed var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all 0.2s;
}

.upload-btn:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    background: var(--color-primary-light);
}

.unsplash-section {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.unsplash-search-row {
    display: flex;
    align-items: center;
    gap: 10px;
}

.unsplash-search-row .text-input.full-width {
    flex: 1;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 13px;
    white-space: nowrap;
    flex-shrink: 0;
}

.unsplash-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 8px;
    min-height: 0;
}

.unsplash-thumb {
    position: relative;
    padding: 0;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    overflow: hidden;
    cursor: pointer;
    aspect-ratio: 4 / 3;
    background: var(--color-bg);
    transition: border-color 0.2s, transform 0.15s, box-shadow 0.2s;
}

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

.unsplash-thumb:hover {
    transform: scale(1.03);
}

.unsplash-thumb.is-active {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 1px var(--color-primary);
}

.unsplash-attribution {
    font-size: 12px;
    color: var(--color-text-secondary);
}

.unsplash-attribution a {
    color: var(--color-primary);
    text-decoration: none;
}

.unsplash-attribution a:hover {
    text-decoration: underline;
}

.unsplash-credit {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    background: var(--color-surface);
}

.unsplash-credit-heading {
    margin: 0;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text);
}

.unsplash-credit-block {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.unsplash-credit-label {
    font-size: 12px;
    color: var(--color-text-secondary);
}

.unsplash-credit-row {
    display: flex;
    align-items: stretch;
    gap: 8px;
}

.unsplash-credit-input {
    flex: 1;
    min-width: 0;
    padding: 8px 10px;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    font-size: 12px;
    line-height: 1.5;
    color: var(--color-text);
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    resize: vertical;
}

.unsplash-credit-preview-label {
    margin: 0;
    font-size: 12px;
    color: var(--color-text-secondary);
}

.unsplash-credit-preview {
    margin: 0;
    font-size: 13px;
    color: var(--color-text);
}

.unsplash-credit-preview a {
    color: var(--color-primary);
    text-decoration: none;
}

.unsplash-credit-preview a:hover {
    text-decoration: underline;
}

.bg-presets {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.presets-label {
    font-size: 12px;
    color: var(--color-text-secondary);
    margin-top: 4px;
}

.presets-grid {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 8px;
}

.preset-swatch {
    width: 100%;
    aspect-ratio: 1;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    padding: 0;
    transition: border-color 0.2s, transform 0.15s, box-shadow 0.2s;
}

.preset-swatch:hover {
    transform: scale(1.06);
}

.preset-swatch.is-active {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 1px var(--color-primary);
}

.mask-control {
    display: flex;
    align-items: center;
    gap: 6px;
    flex-shrink: 0;
}

.mask-label {
    font-size: 13px;
    color: var(--color-text-secondary);
    white-space: nowrap;
}

.mask-input {
    width: 52px;
    padding: 8px 6px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    text-align: center;
    background: var(--color-surface);
    color: var(--color-text);
    outline: none;
}

.mask-input:focus {
    border-color: var(--color-primary);
}

/* Action Bar */
.action-bar {
    display: flex;
    justify-content: center;
    gap: 12px;
}

.btn {
    padding: 10px 28px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--color-primary-hover);
}

.btn-secondary {
    background: var(--color-surface);
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    background: var(--color-bg);
}

/* ===== Footer ===== */
.site-footer {
    --footer-bg: #1e293b;
    --footer-text: #f1f5f9;
    --footer-text-muted: #94a3b8;
    --footer-border: #334155;
    --footer-card-bg: #273449;
    background: var(--footer-bg);
    color: var(--footer-text);
    padding: 48px 24px 28px;
    margin-top: auto;
}

.footer-wrap {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.footer-main {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 40px;
}

.footer-about {
    flex: 1;
    min-width: 0;
}

.footer-title {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--footer-text);
}

.footer-desc {
    font-size: 14px;
    color: var(--footer-text-muted);
    line-height: 1.8;
    max-width: 560px;
}

.footer-qrcodes {
    display: flex;
    align-items: flex-start;
    gap: 24px;
    flex-shrink: 0;
}

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

.footer-qrcode-box {
    width: 108px;
    height: 108px;
    border-radius: var(--radius-sm);
    overflow: hidden;
    background: var(--footer-card-bg);
    border: 1px solid var(--footer-border);
}

.footer-qrcode-box img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.footer-qrcode-box.is-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    border-style: dashed;
    background: rgba(255, 255, 255, 0.03);
}

.footer-qrcode-placeholder {
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 0.08em;
    color: var(--footer-text-muted);
    opacity: 0.7;
}

.footer-qrcode-label {
    font-size: 12px;
    color: var(--footer-text-muted);
    text-align: center;
    white-space: nowrap;
}

.footer-bottom {
    padding-top: 20px;
    border-top: 1px solid var(--footer-border);
    text-align: center;
}

.footer-copyright {
    font-size: 12px;
    color: var(--footer-text-muted);
    line-height: 1.6;
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
    .text-blocks-grid {
        grid-template-columns: 1fr;
    }

    .presets-grid {
        grid-template-columns: repeat(5, 1fr);
    }

    .unsplash-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .unsplash-credit-row {
        flex-direction: column;
    }

    .footer-main {
        flex-direction: column;
        gap: 28px;
    }

    .footer-qrcodes {
        align-self: flex-start;
    }
}

@media (max-width: 600px) {
    .site-main {
        padding: 20px 16px 32px;
    }

    .preview-stage {
        height: 360px;
    }

    .bg-tab {
        font-size: 12px;
        padding: 8px 6px;
    }

    .header-brand-inner,
    .header-main-inner {
        padding: 0 16px;
    }

    .brand-tagline {
        display: none;
    }

    .tool-logo-name {
        font-size: 17px;
    }

    .site-footer {
        padding: 36px 16px 24px;
    }

    .footer-qrcodes {
        align-self: stretch;
        justify-content: center;
    }

    .tool-logo-desc {
        display: none;
    }
}