:root {
    --primary-color: #007bff;
    --tool-bg: #f3f5f8;
    --panel-bg: #ffffff;
    --card-bg: #ffffff;
    --border-color: #dee2e6;
    --text-primary: #212934;
    --text-secondary: #5f6b7a;
    --text-light: #7f8a98;
    --btn-bg: #f8f9fa;
    --btn-hover-bg: #e9ecef;
    --success-color: #28a745;
    --warning-bg: #f8f9ff;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    padding: 24px;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--tool-bg);
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
}

.page-shell {
    max-width: 1360px;
    margin: 0 auto;
}

.hero-card,
.controls-card,
.list-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 18px;
    box-shadow: 0 8px 28px rgba(15, 23, 42, 0.06);
}

.hero-card {
    padding: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
    margin-bottom: 20px;
}

.hero-card h1 {
    margin: 0 0 10px;
    font-size: 30px;
}

.hero-card p {
    margin: 0;
    max-width: 800px;
    color: var(--text-secondary);
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.workspace-grid {
    display: grid;
    grid-template-columns: 340px 1fr;
    gap: 20px;
    min-height: calc(100vh - 160px);
}

.controls-card,
.list-card {
    padding: 22px;
}

.controls-card h2,
.list-card h2 {
    margin: 0 0 14px;
    font-size: 18px;
}

.field-label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 600;
}

select,
input[type="number"],
input[type="color"] {
    width: 100%;
    padding: 11px 12px;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    background: var(--panel-bg);
    color: var(--text-primary);
    font-size: 14px;
    margin-bottom: 16px;
}

input[type="color"] {
    min-height: 44px;
    padding: 6px;
}

.field-row.two-cols {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.primary-btn,
.ghost-btn,
.download-btn {
    border: none;
    border-radius: 12px;
    padding: 12px 18px;
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.15s ease, opacity 0.2s ease, background-color 0.2s ease;
}

.primary-btn:hover,
.ghost-btn:hover,
.download-btn:hover { transform: translateY(-1px); }

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

.ghost-btn {
    background: var(--btn-bg);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.download-btn {
    width: 100%;
    background: var(--success-color);
    color: #fff;
    margin-top: 8px;
}

.download-btn:disabled {
    opacity: 0.7;
    cursor: wait;
}

.summary-box {
    padding: 14px;
    border-radius: 12px;
    background: var(--warning-bg);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    margin: 8px 0 12px;
    font-size: 14px;
    line-height: 1.6;
}

.tips-text {
    font-size: 13px;
    color: var(--text-light);
    line-height: 1.7;
    margin: 14px 0 0;
}

.list-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 14px;
}

.list-header span {
    color: var(--text-secondary);
    font-size: 14px;
}

.empty-state {
    height: 100%;
    min-height: 340px;
    border: 2px dashed var(--border-color);
    border-radius: 16px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: var(--text-secondary);
    text-align: center;
    padding: 30px;
}

.empty-icon {
    font-size: 48px;
    margin-bottom: 12px;
}

.empty-state p {
    margin: 0 0 8px;
    font-size: 20px;
    color: var(--text-primary);
}

.empty-state span {
    color: var(--text-light);
    line-height: 1.6;
}

.file-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 16px;
}

.file-card {
    border: 1px solid var(--border-color);
    border-radius: 16px;
    overflow: hidden;
    background: var(--panel-bg);
}

.file-thumb {
    height: 160px;
    background: var(--tool-bg);
    display: flex;
    align-items: center;
    justify-content: center;
}

.file-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.file-meta {
    padding: 12px;
}

.file-name {
    font-size: 14px;
    font-weight: 700;
    line-height: 1.5;
    word-break: break-word;
    margin-bottom: 8px;
}

.file-size,
.file-dimension {
    font-size: 12px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.progress-area {
    margin-top: 16px;
    padding: 14px;
    border-radius: 12px;
    background: var(--warning-bg);
    border: 1px solid var(--border-color);
    font-size: 14px;
    color: var(--text-primary);
}

.hidden { display: none !important; }

body.dark-mode {
    --primary-color: #3d8bfd;
    --tool-bg: #1e2128;
    --panel-bg: #2a2e37;
    --card-bg: #2a2e37;
    --border-color: #495160;
    --text-primary: #e5e7eb;
    --text-secondary: #b5becb;
    --text-light: #9aa4b2;
    --btn-bg: #363c48;
    --btn-hover-bg: #48505f;
    --success-color: #20c997;
    --warning-bg: #20252f;
}

@media (max-width: 1024px) {
    .workspace-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 720px) {
    body { padding: 16px; }

    .hero-card {
        flex-direction: column;
        align-items: flex-start;
    }

    .hero-card h1 {
        font-size: 24px;
    }

    .field-row.two-cols {
        grid-template-columns: 1fr;
    }

    .file-list {
        grid-template-columns: 1fr;
    }
}