:root {
    --primary-color: #0f4c75;
    /* Deep Blue */
    --secondary-color: #3282b8;
    --accent-color: #bbe1fa;
    --text-color: #1b262c;
    --bg-color: #f0f5f9;
    --white: #ffffff;
    --success-color: #28a745;
    --border-radius: 8px;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
    width: 100%;
}

/* Header */
.app-header {
    background-color: var(--white);
    box-shadow: var(--shadow);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.app-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-color);
}

.logo h1 {
    font-size: 1.25rem;
    font-weight: 700;
}

.main-nav {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.nav-btn {
    background: none;
    border: none;
    padding: 0.5rem 1rem;
    cursor: pointer;
    font-family: inherit;
    font-weight: 500;
    color: var(--text-color);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

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

.nav-btn.active {
    background-color: var(--primary-color);
    color: var(--white);
}

/* Main Content */
main {
    flex: 1;
    padding: 2rem 0;
}

.privacy-badge {
    background-color: #e8f5e9;
    /* Light Green */
    color: #2e7d32;
    padding: 0.75rem 1rem;
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 2rem;
    font-size: 0.9rem;
    border: 1px solid #c8e6c9;
}

.tool-section {
    display: none;
    background: var(--white);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    animation: fadeIn 0.3s ease;
}

.tool-section.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.tool-header {
    text-align: center;
    margin-bottom: 2rem;
}

.tool-header h2 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

/* Drop Zone */
.drop-zone {
    border: 2px dashed var(--secondary-color);
    border-radius: var(--border-radius);
    padding: 3rem 1rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    background-color: #f8fbff;
    margin-bottom: 1.5rem;
}

.drop-zone:hover,
.drop-zone.drag-over {
    background-color: var(--accent-color);
    border-color: var(--primary-color);
}

.drop-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    color: var(--secondary-color);
}

/* File List */
.file-list {
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.file-item {
    background: var(--bg-color);
    padding: 0.75rem;
    border-radius: var(--border-radius);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.9rem;
    gap: 1rem;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex: 1;
}

.preview-thumb {
    width: 60px;
    height: 80px;
    object-fit: contain;
    background: #fff;
    border: 1px solid #ddd;
    border-radius: 4px;
}

.preview-container {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

.preview-large {
    max-width: 100%;
    max-height: 300px;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

.remove-file {
    background: none;
    border: none;
    color: #dc3545;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 0 0.5rem;
}

/* Options Area */
.options-area {
    margin-bottom: 1.5rem;
    padding: 1rem;
    background-color: var(--bg-color);
    border-radius: var(--border-radius);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.hidden {
    display: none !important;
}

.option-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

select,
input[type="text"] {
    padding: 0.5rem;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-family: inherit;
}

/* Action Area */
.action-area {
    text-align: center;
}

.primary-btn {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    padding: 1rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    min-width: 200px;
}

.primary-btn:hover:not(:disabled) {
    background-color: #0a3655;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(15, 76, 117, 0.3);
}

.primary-btn:disabled {
    background-color: #ccc;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

/* Footer */
.app-footer {
    margin-top: auto;
    padding: 1.5rem 0;
    text-align: center;
    color: #666;
    font-size: 0.85rem;
    border-top: 1px solid #eee;
}

/* Responsive */
@media (max-width: 600px) {
    .app-header .container {
        flex-direction: column;
        align-items: stretch;
    }

    .main-nav {
        justify-content: center;
    }

    .nav-btn {
        flex: 1;
        text-align: center;
        font-size: 0.9rem;
        padding: 0.5rem;
    }
}