:root {
    --primary: #4F46E5;
    --primary-hover: #4338CA;
    --bg: #F3F4F6;
    --card-bg: #FFFFFF;
    --text: #1F2937;
    --text-muted: #6B7280;
    --border: #E5E7EB;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

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

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

.header {
    background-color: var(--card-bg);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 10;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.lang-selector select {
    padding: 0.5rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    background-color: var(--card-bg);
    font-family: inherit;
    font-size: 0.875rem;
    cursor: pointer;
    outline: none;
    transition: all 0.2s;
}

.lang-selector select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(79, 70, 229, 0.2);
}

.header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.global-rotations {
    display: flex;
    gap: 0.5rem;
}

.secondary-btn {
    background-color: var(--card-bg);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    flex-grow: 1;
    width: 100%;
}

/* Dropzone */
.dropzone {
    background-color: var(--card-bg);
    border: 2px dashed var(--border);
    border-radius: 12px;
    padding: 4rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 300px;
}

.dropzone:hover,
.dropzone.dragover {
    border-color: var(--primary);
    background-color: rgba(79, 70, 229, 0.05);
}

.dropzone-content svg {
    color: var(--primary);
    margin-bottom: 1rem;
}

.dropzone-content p {
    font-size: 1.125rem;
    color: var(--text-muted);
}

/* Loading */
.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem;
    min-height: 300px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid rgba(79, 70, 229, 0.2);
    border-radius: 50%;
    border-top-color: var(--primary);
    animation: spin 1s ease-in-out infinite;
    margin-bottom: 1rem;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Workspace */
.hidden {
    display: none !important;
}

.toolbar {
    display: flex;
    justify-content: flex-end;
    margin-bottom: 2rem;
}

.primary-btn {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    box-shadow: var(--shadow);
}

.primary-btn:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.primary-btn:active {
    transform: translateY(0);
}

.primary-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 2rem;
}

/* Thumbnail Card */
.thumbnail-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.2s;
    display: flex;
    flex-direction: column;
}

.thumbnail-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.canvas-container {
    position: relative;
    padding: 1rem;
    background-color: #f9fafb;
    display: flex;
    justify-content: center;
    align-items: center;
    aspect-ratio: 1/1.414;
    /* A4 aspect ratio approx */
    overflow: hidden;
}

.canvas-container canvas {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

.page-info {
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border);
    background-color: var(--card-bg);
    z-index: 2;
}

.page-num {
    font-weight: 500;
    font-size: 0.875rem;
    color: var(--text-muted);
}

.rotate-btn {
    background: none;
    border: none;
    color: var(--primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem;
    border-radius: 50%;
    transition: background-color 0.2s;
}

.rotate-btn:hover {
    background-color: rgba(79, 70, 229, 0.1);
}

.rotate-btn svg {
    width: 20px;
    height: 20px;
}

.page-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.include-checkbox {
    width: 1.25rem;
    height: 1.25rem;
    cursor: pointer;
    accent-color: var(--primary);
}