:root {
    --brand-green: #01894d;
    --brand-orange: #f39800;
    --bg-color: #f8fafb;
    --card-bg: #ffffff;
    --text-main: #333333;
    --text-sub: #666666;
    --border-color: #e5e7eb;
    --accent-color: #f0fdf4;
    --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 16px;
}

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

body {
    font-family: 'Outfit', 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Header */
.main-header {
    background: rgba(1, 137, 77, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 2px solid var(--brand-orange);
    padding: 12px 0;
    color: #fff;
    position: sticky;
    top: 0;
    z-index: 100;
}

.main-header-inner {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.title-icon {
    width: 28px;
    height: 28px;
}

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

.btn-home {
    color: #fff;
    text-decoration: none;
    font-weight: 600;
    padding: 8px 16px;
    border-radius: 8px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    background: rgba(255, 255, 255, 0.1);
}

.btn-home:hover {
    background-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-1px);
}

.container {
    max-width: 900px;
    margin: 40px auto;
    padding: 0 20px;
}

/* Info Section (Accordion) */
.info-section {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    margin-bottom: 32px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.info-header {
    padding: 20px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    background: #fcfcfc;
    border: none;
    width: 100%;
    text-align: left;
}

.info-header h2 {
    font-size: 1.1rem;
    color: var(--brand-green);
    display: flex;
    align-items: center;
    gap: 10px;
}

.toggle-icon {
    width: 24px;
    height: 24px;
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.info-section.collapsed .toggle-icon {
    transform: rotate(-180deg);
}

.info-content {
    padding: 24px;
    border-top: 1px solid var(--border-color);
    display: block;
    animation: slideDown 0.4s ease-out;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

.info-section.collapsed .info-content {
    display: none;
}

.usage-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
    margin-top: 20px;
}

.usage-step {
    padding: 20px;
    padding-left: 48px;
    position: relative;
    font-size: 0.95rem;
    background: var(--accent-color);
    border-radius: 12px;
}

.usage-step::before {
    content: attr(data-step);
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    width: 28px;
    height: 28px;
    background: var(--brand-green);
    color: #fff;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

/* Cards */
.card {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 32px;
    margin-bottom: 32px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease;
}

.form-title {
    font-size: 1.3rem;
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--brand-green);
}

.section-number {
    background: var(--brand-orange);
    color: #fff;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1rem;
    font-weight: bold;
}

/* Drop Zone */
.drop-zone {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius);
    padding: 60px 40px;
    text-align: center;
    color: var(--text-sub);
    transition: all 0.3s ease;
    background: #fafafa;
    cursor: pointer;
}

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

.file-label {
    display: inline-block;
    margin-top: 15px;
    background: var(--brand-green);
    color: #fff;
    padding: 12px 32px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s;
}

.file-label:hover {
    transform: scale(1.05);
    box-shadow: 0 10px 15px -3px rgba(1, 137, 77, 0.3);
}

.file-list {
    margin-top: 24px;
    max-height: 300px;
    overflow-y: auto;
    padding-right: 8px;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: #f8fafb;
    border-radius: 8px;
    margin-bottom: 8px;
    font-size: 0.9rem;
    animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.remove-file {
    background: none;
    border: none;
    color: #ef4444;
    cursor: pointer;
    padding: 4px;
}

/* Settings */
.settings-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 32px;
    margin-bottom: 32px;
}

.form-group label {
    display: block;
    margin-bottom: 12px;
    font-weight: 600;
    font-size: 1rem;
    color: var(--text-main);
}

.mode-status-badge {
    display: inline-block;
    padding: 8px 16px;
    background: var(--accent-color);
    color: var(--brand-green);
    border: 1px solid var(--brand-green);
    border-radius: 20px;
    font-weight: 700;
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.radio-group label {
    font-weight: normal;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
}

input[type="radio"] {
    width: 18px;
    height: 18px;
    accent-color: var(--brand-green);
}

input[type="range"] {
    width: 100%;
    accent-color: var(--brand-green);
    height: 6px;
    background: #e5e7eb;
    border-radius: 3px;
    outline: none;
}

.convert-btn {
    width: 100%;
    background: linear-gradient(135deg, var(--brand-green), #02a960);
    color: #fff;
    border: none;
    padding: 20px;
    font-size: 1.2rem;
    font-weight: 700;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 10px 15px -3px rgba(1, 137, 77, 0.2);
}

.convert-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px rgba(1, 137, 77, 0.3);
}

.convert-btn:active:not(:disabled) {
    transform: translateY(0);
}

.convert-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background: #ccc;
    box-shadow: none;
}

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

.result-actions {
    margin-bottom: 32px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.result-stats {
    font-weight: 600;
    color: var(--text-sub);
}

.download-all-btn {
    background: var(--brand-orange);
    color: #fff;
    border: none;
    padding: 12px 28px;
    border-radius: 10px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 10px 15px -3px rgba(243, 152, 0, 0.3);
}

.download-all-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px rgba(243, 152, 0, 0.4);
}

.result-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 20px;
}

.result-item {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 16px;
    text-align: center;
    transition: transform 0.2s;
    position: relative;
    overflow: hidden;
}

.result-item:hover {
    transform: translateY(-5px);
    border-color: var(--brand-green);
}

.preview-container {
    width: 100%;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #f1f5f9;
    border-radius: 8px;
    margin-bottom: 12px;
    overflow: hidden;
}

.result-item img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.pdf-placeholder {
    font-size: 2rem;
}

.result-item .item-name {
    font-size: 0.8rem;
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-bottom: 10px;
    color: var(--text-main);
}

.download-btn {
    display: block;
    background: var(--accent-color);
    color: var(--brand-green);
    text-decoration: none;
    padding: 8px;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 700;
    transition: all 0.2s;
}

.download-btn:hover {
    background: var(--brand-green);
    color: #fff;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(8px);
    color: #fff;
    padding: 14px 28px;
    border-radius: 50px;
    font-size: 0.95rem;
    font-weight: 600;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    opacity: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    gap: 10px;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(5px);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--accent-color);
    border-top: 4px solid var(--brand-green);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (max-width: 600px) {
    .container {
        margin: 20px auto;
    }
    .card {
        padding: 20px;
    }
    .usage-steps {
        grid-template-columns: 1fr;
    }
    .settings-grid {
        grid-template-columns: 1fr;
    }
}