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

:root {
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --accent-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --success-gradient: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
    --background-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    --card-bg: rgba(255, 255, 255, 0.95);
    --text-primary: #2d3748;
    --text-secondary: #718096;
    --border-radius: 20px;
    --shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 25px 50px rgba(0, 0, 0, 0.15);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--background-gradient);
    min-height: 100vh;
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 80%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(120, 219, 255, 0.2) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    margin-bottom: 40px;
    color: white;
    position: relative;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    /* max-width: 1000px; */
    margin: 0 0 0 0;
}

.header-left {
    text-align: left;
}

.header-right {
    text-align: right;
}

.title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 15px;
    text-shadow: 0 4px 8px rgba(0,0,0,0.3);
    background: linear-gradient(45deg, #fff, #f0f0f0, #fff);
    background-size: 200% 200%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: shimmer 3s ease-in-out infinite;
}

@keyframes shimmer {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.subtitle {
    font-size: 1.2rem;
    font-weight: 400;
    opacity: 0.9;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.share-btn {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    padding: 12px 24px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: blur(10px);
    text-shadow: 0 1px 2px rgba(0,0,0,0.2);
}

.share-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.5);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.2);
}

.about-link, .home-link {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    padding: 12px 24px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: blur(10px);
    text-shadow: 0 1px 2px rgba(0,0,0,0.2);
    text-decoration: none;
    display: inline-block;
    margin-right: 15px;
}

.about-link:hover, .home-link:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.5);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.2);
    text-decoration: none;
    color: white;
}

.main {
    flex: 1;
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 50px;
    box-shadow: var(--shadow);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
}

.main::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 0;
    background: var(--primary-gradient);
}

.upload-section {
    margin-bottom: 40px;
}

.upload-area {
    border: 3px dashed rgba(102, 126, 234, 0.3);
    border-radius: var(--border-radius);
    padding: 60px 40px;
    text-align: center;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.upload-area::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: left 0.5s;
}

.upload-area:hover::before {
    left: 100%;
}

.upload-area:hover {
    border-color: #667eea;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(102, 126, 234, 0.2);
}

.upload-area.dragover {
    border-color: #667eea;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.15) 0%, rgba(118, 75, 162, 0.15) 100%);
    transform: scale(1.02);
    box-shadow: 0 20px 40px rgba(102, 126, 234, 0.3);
}

.upload-content {
    max-width: 400px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: 25px;
    display: inline-block;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

.upload-area h3 {
    font-size: 1.8rem;
    margin-bottom: 15px;
    color: var(--text-primary);
    font-weight: 600;
}

.upload-area p {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1.1rem;
}

.upload-btn {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 15px 35px;
    border-radius: 50px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
    position: relative;
    overflow: hidden;
}

.upload-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.upload-btn:hover::before {
    left: 100%;
}

.upload-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(102, 126, 234, 0.6);
}

.image-preview-container {
    margin-top: 30px;
    animation: slideUp 0.6s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.preview-image-wrapper {
    position: relative;
    display: inline-block;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    background: white;
}

.preview-image-wrapper:hover {
    transform: scale(1.02) translateY(-3px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.2);
}

.preview-image {
    width: 300px;
    height: 300px;
    object-fit: cover;
    display: block;
}

.remove-preview-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(239, 68, 68, 0.9);
    color: white;
    border: none;
    border-radius: 50%;
    width: 35px;
    height: 35px;
    cursor: pointer;
    font-size: 18px;
    font-weight: bold;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    justify-content: center;
}

.remove-preview-btn:hover {
    background: rgba(239, 68, 68, 1);
    transform: scale(1.1);
}



.action-section {
    text-align: center;
    margin-bottom: 40px;
    animation: slideUp 0.6s ease-out 0.1s both;
}

/* プログレスバーセクション */
.progress-section {
    margin-bottom: 40px;
    animation: slideUp 0.6s ease-out;
}

.progress-container {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-radius: var(--border-radius);
    padding: 40px;
    border: 2px solid rgba(102, 126, 234, 0.1);
    position: relative;
    overflow: hidden;
}

.progress-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(102, 126, 234, 0.1), transparent);
    animation: shimmer 2s infinite;
}

.progress-header {
    text-align: center;
    margin-bottom: 30px;
}

.progress-header h3 {
    font-size: 1.8rem;
    color: var(--text-primary);
    margin-bottom: 10px;
    font-weight: 600;
}

.progress-status {
    font-size: 1.1rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.progress-bar-wrapper {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 40px;
}

.progress-bar {
    flex: 1;
    height: 12px;
    background: rgba(102, 126, 234, 0.1);
    border-radius: 10px;
    overflow: hidden;
    position: relative;
}

.progress-fill {
    height: 100%;
    background: var(--primary-gradient);
    border-radius: 10px;
    width: 0%;
    transition: width 0.5s ease-out;
    position: relative;
    overflow: hidden;
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    animation: progressShimmer 1.5s infinite;
}

@keyframes progressShimmer {
    0% { left: -100%; }
    100% { left: 100%; }
}

.progress-percentage {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
    min-width: 60px;
    text-align: center;
}

.progress-steps {
    display: flex;
    justify-content: space-between;
    margin-bottom: 30px;
    position: relative;
}

.progress-steps::before {
    content: '';
    position: absolute;
    top: 25px;
    left: 30px;
    right: 30px;
    height: 2px;
    background: rgba(102, 126, 234, 0.2);
    z-index: 1;
}

.step {
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    z-index: 2;
    transition: all 0.3s ease;
}

.step-icon {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: rgba(102, 126, 234, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 10px;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.step-text {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-align: center;
    font-weight: 500;
    transition: all 0.3s ease;
}

.step.active .step-icon {
    background: var(--primary-gradient);
    color: white;
    transform: scale(1.1);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

.step.active .step-text {
    color: var(--text-primary);
    font-weight: 600;
}

.step.completed .step-icon {
    background: var(--success-gradient);
    color: white;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.step.completed .step-text {
    color: #38a169;
    font-weight: 600;
}

.progress-time {
    text-align: center;
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* 広告セクション */
.ad-section {
    margin-top: 30px;
    margin-bottom: 40px;
    animation: slideUp 0.6s ease-out 0.3s both;
}

.ad-container {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(248, 250, 252, 0.9) 100%);
    border-radius: 15px;
    padding: 20px;
    border: 1px solid rgba(102, 126, 234, 0.1);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.ad-label {
    text-align: center;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 15px;
    font-weight: 500;
    opacity: 0.7;
}

.ad-content {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 90px;
}

.ad-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
    opacity: 0.6;
}

.ad-placeholder-icon {
    font-size: 2rem;
}

.ad-placeholder-text {
    font-size: 0.9rem;
    font-weight: 500;
}

/* Google AdSense広告のスタイル調整 */
.ad-content ins {
    display: block !important;
    margin: 0 auto !important;
}

.ad-content iframe {
    border: none !important;
    border-radius: 8px !important;
}

/* サンプルセクション */
.sample-section {
    margin-bottom: 40px;
    animation: slideUp 0.6s ease-out 0.2s both;
}

/* このサイトとは？セクション */
.about-section {
    margin-bottom: 50px;
    animation: slideUp 0.6s ease-out 0.4s both;
}

.about-header {
    text-align: center;
    margin-bottom: 40px;
}

.about-header h2 {
    font-size: 2.2rem;
    color: var(--text-primary);
    margin-bottom: 15px;
    font-weight: 700;
}

.about-header p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.about-content {
    max-width: 1000px;
    margin: 0 auto;
}

.about-main {
    margin-bottom: 50px;
}

.about-main h3 {
    font-size: 1.6rem;
    color: var(--text-primary);
    margin-bottom: 20px;
    font-weight: 600;
}

.about-main p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.about-feature {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    padding: 25px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-radius: 15px;
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.about-feature:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.15);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
}

.about-feature-icon {
    font-size: 2.5rem;
    min-width: 60px;
    text-align: center;
}

.about-feature-content h4 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: 10px;
    font-weight: 600;
}

.about-feature-content p {
    font-size: 1rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin: 0;
}

.about-comparison {
    margin-bottom: 50px;
}

.about-comparison h3 {
    font-size: 1.6rem;
    color: var(--text-primary);
    margin-bottom: 25px;
    font-weight: 600;
    text-align: center;
}

.comparison-table {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
}

.comparison-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    border-bottom: 1px solid rgba(102, 126, 234, 0.1);
}

.comparison-row:last-child {
    border-bottom: none;
}

.comparison-header {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    font-weight: 600;
}

.comparison-item {
    padding: 20px;
    display: flex;
    align-items: center;
    font-size: 1rem;
    line-height: 1.5;
}

.comparison-header .comparison-item {
    font-weight: 600;
    color: var(--text-primary);
}

.comparison-row:not(.comparison-header) .comparison-item {
    color: var(--text-secondary);
}

.comparison-row:not(.comparison-header) .comparison-item:first-child {
    font-weight: 600;
    color: var(--text-primary);
}

.about-use-cases {
    margin-bottom: 50px;
}

.about-use-cases h3 {
    font-size: 1.6rem;
    color: var(--text-primary);
    margin-bottom: 25px;
    font-weight: 600;
    text-align: center;
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.use-case {
    text-align: center;
    padding: 30px 20px;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(248, 250, 252, 0.9) 100%);
    border-radius: 15px;
    border: 1px solid rgba(102, 126, 234, 0.1);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.use-case:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(102, 126, 234, 0.15);
}

.use-case-icon {
    font-size: 3rem;
    margin-bottom: 15px;
    display: block;
}

.use-case h4 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: 15px;
    font-weight: 600;
}

.use-case p {
    font-size: 1rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin: 0;
}

.about-technology {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    padding: 30px;
    border-radius: 15px;
    border: 1px solid rgba(102, 126, 234, 0.1);
}

.about-technology h3 {
    font-size: 1.6rem;
    color: var(--text-primary);
    margin-bottom: 20px;
    font-weight: 600;
}

.about-technology p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 15px;
}

.about-technology p:last-child {
    margin-bottom: 0;
}

.about-cta {
    text-align: center;
    margin-top: 50px;
    padding: 40px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border-radius: 20px;
    border: 1px solid rgba(102, 126, 234, 0.2);
}

.about-cta h3 {
    font-size: 1.8rem;
    color: var(--text-primary);
    margin-bottom: 15px;
    font-weight: 600;
}

.about-cta p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.cta-btn {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 18px 40px;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
    text-decoration: none;
    display: inline-block;
    position: relative;
    overflow: hidden;
}

.cta-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.cta-btn:hover::before {
    left: 100%;
}

.cta-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 35px rgba(102, 126, 234, 0.5);
    text-decoration: none;
    color: white;
}

/* 記事コンテンツスタイル */
.article-content {
    max-width: 900px;
    margin: 0 auto;
    line-height: 1.8;
}

.article-content section {
    margin-bottom: 50px;
}

.article-content h2 {
    font-size: 2.2rem;
    color: var(--text-primary);
    margin-bottom: 25px;
    font-weight: 700;
    line-height: 1.3;
}

.article-content h3 {
    font-size: 1.8rem;
    color: var(--text-primary);
    margin-bottom: 20px;
    font-weight: 600;
    margin-top: 40px;
}

.article-content h4 {
    font-size: 1.4rem;
    color: var(--text-primary);
    margin-bottom: 15px;
    font-weight: 600;
}

.article-content h5 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: 10px;
    font-weight: 600;
}

.article-content p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
    line-height: 1.8;
}

.article-content ul {
    margin-bottom: 20px;
    padding-left: 20px;
}

.article-content li {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    line-height: 1.6;
}

.highlight-box {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border: 2px solid rgba(102, 126, 234, 0.2);
    border-radius: 15px;
    padding: 25px;
    margin: 30px 0;
}

.highlight-box p {
    margin-bottom: 15px;
    font-size: 1.1rem;
    color: var(--text-primary);
}

.highlight-box p:last-child {
    margin-bottom: 0;
}

/* 特長カード */
.feature-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.feature-card {
    background: white;
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(102, 126, 234, 0.15);
}

.feature-card .feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    display: block;
}

.feature-card h5 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--text-primary);
}

.feature-card p {
    font-size: 1rem;
    line-height: 1.6;
    margin: 0;
}

/* ステップカード */
.step-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.step-card {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(248, 250, 252, 0.9) 100%);
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
    position: relative;
    transition: all 0.3s ease;
}

.step-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.15);
}

.step-number {
    position: absolute;
    top: -15px;
    left: 30px;
    background: var(--primary-gradient);
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.2rem;
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
}

.step-card h5 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--text-primary);
    margin-top: 10px;
}

.step-card p {
    font-size: 1rem;
    line-height: 1.6;
    margin: 0;
}

/* コツカード */
.tip-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.tip-card {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-radius: 15px;
    padding: 25px;
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.tip-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.15);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
}

.tip-card h5 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--text-primary);
}

.tip-card p {
    font-size: 1rem;
    line-height: 1.6;
    margin: 0;
}

/* 活用事例カード */
.use-case-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.use-case-card {
    background: white;
    border-radius: 15px;
    padding: 25px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
    text-align: center;
}

.use-case-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(102, 126, 234, 0.15);
}

.use-case-card h5 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--text-primary);
}

.use-case-card p {
    font-size: 1rem;
    line-height: 1.6;
    margin: 0;
}

/* FAQ */
.faq-item {
    background: white;
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 20px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.faq-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.15);
}

.faq-item h5 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--text-primary);
}

.faq-item p {
    font-size: 1rem;
    line-height: 1.6;
    margin: 0;
}

/* 技術セクション */
.tech-section {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    padding: 30px;
    border-radius: 15px;
    border: 1px solid rgba(102, 126, 234, 0.1);
}

/* まとめセクション */
.conclusion-section {
    text-align: center;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    padding: 40px;
    border-radius: 20px;
    border: 1px solid rgba(102, 126, 234, 0.2);
}

.cta-section {
    margin-top: 30px;
}

.sample-header {
    text-align: center;
    margin-bottom: 30px;
}

.sample-header h3 {
    font-size: 1.8rem;
    color: var(--text-primary);
    margin-bottom: 10px;
    font-weight: 600;
}

.sample-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.sample-container {
    margin-bottom: 40px;
}

.sample-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.sample-before, .sample-after {
    text-align: center;
    flex: 1;
    min-width: 200px;
}

.sample-before h4, .sample-after h4 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: 15px;
    font-weight: 600;
}

.sample-before img, .sample-after img {
    width: 200px;
    height: 300px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
    transition: transform 0.3s ease;
    object-fit: cover;
}

.sample-before img:hover, .sample-after img:hover {
    transform: scale(1.05);
}

.sample-arrow {
    font-size: 2rem;
    color: var(--text-secondary);
    animation: pulse 2s infinite;
}

.sample-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 20px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-radius: 15px;
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.15);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
}

.feature-icon {
    font-size: 2rem;
    min-width: 50px;
    text-align: center;
}

.feature-text h4 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 5px;
    font-weight: 600;
}

.feature-text p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.4;
}

/* 履歴セクション */
.history-section {
    margin-top: 50px;
    animation: slideUp 0.6s ease-out 0.5s both;
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
    gap: 20px;
}

.history-header h3 {
    font-size: 1.8rem;
    color: var(--text-primary);
    font-weight: 600;
    margin: 0;
}

.clear-history-btn {
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a52 100%);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 5px 15px rgba(255, 107, 107, 0.4);
}

.clear-history-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 107, 107, 0.6);
}

.history-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.history-item {
    background: white;
    border-radius: 15px;
    padding: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.history-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
}

.history-item img {
    width: 100%;
    height: 150px;
    object-fit: cover;
    object-position: top;
    border-radius: 10px;
    margin-bottom: 10px;
    transition: transform 0.3s ease;
}

.history-item:hover img {
    transform: scale(1.05);
}

.history-item-info {
    text-align: center;
}

.history-item-title {
    font-size: 0.9rem;
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 5px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.history-item-date {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
}

.history-item-actions {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.history-item-btn {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    flex: 1;
}

.history-item-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.history-item-btn.delete {
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a52 100%);
}

.history-item-btn.delete:hover {
    box-shadow: 0 5px 15px rgba(255, 107, 107, 0.4);
}

.history-item-btn:disabled {
    background: linear-gradient(135deg, #cbd5e0 0%, #a0aec0 100%);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.download-btn:disabled {
    background: linear-gradient(135deg, #cbd5e0 0%, #a0aec0 100%);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.history-empty {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

.history-empty-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    opacity: 0.5;
}

.history-empty-text {
    font-size: 1.1rem;
    font-weight: 500;
}

.generate-btn {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 18px 50px;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
    min-width: 250px;
    position: relative;
    overflow: hidden;
}

.generate-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.generate-btn:hover:not(:disabled)::before {
    left: 100%;
}

.generate-btn:hover:not(:disabled) {
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.6);
}

.generate-btn:disabled {
    background: linear-gradient(135deg, #cbd5e0 0%, #a0aec0 100%);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.loading-spinner {
    animation: spin 1s linear infinite;
    font-size: 1.2rem;
}

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

.result-section {
    text-align: center;
    margin-top: 50px;
    animation: slideUp 0.6s ease-out 0.3s both;
}

.result-section h3 {
    margin-bottom: 30px;
    color: var(--text-primary);
    font-size: 1.8rem;
    font-weight: 600;
}

.result-container {
    padding: 40px;
}

.generated-image {
    max-width: 100%;
    max-height: 600px;
    border-radius: 15px;
    box-shadow: 0 15px 40px rgba(0,0,0,0.2);
    margin-bottom: 30px;
    transition: transform 0.3s ease;
}

.generated-image:hover {
    transform: scale(1.02);
}

.result-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

.download-btn, .new-generation-btn {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 15px 30px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
    position: relative;
    overflow: hidden;
}

.download-btn::before, .new-generation-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.download-btn:hover::before, .new-generation-btn:hover::before {
    left: 100%;
}

.download-btn:hover, .new-generation-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(102, 126, 234, 0.6);
}

.new-generation-btn {
    background: var(--success-gradient);
    box-shadow: 0 8px 25px rgba(67, 233, 123, 0.4);
}

.new-generation-btn:hover {
    box-shadow: 0 12px 35px rgba(67, 233, 123, 0.6);
}

.error-section {
    margin-top: 30px;
    text-align: center;
    animation: slideUp 0.6s ease-out 0.4s both;
}

.error-message {
    background: linear-gradient(135deg, rgba(248, 215, 218, 0.9) 0%, rgba(245, 198, 203, 0.9) 100%);
    color: #721c24;
    padding: 20px;
    border-radius: 15px;
    border: 1px solid rgba(245, 198, 203, 0.5);
    font-weight: 500;
    backdrop-filter: blur(10px);
    box-shadow: 0 5px 15px rgba(248, 215, 218, 0.3);
}

.footer {
    text-align: center;
    margin-top: 50px;
    color: white;
    opacity: 0.8;
    font-weight: 300;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .main {
        padding: 30px 20px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }
    
    .header-left {
        text-align: center;
    }
    
    .header-right {
        text-align: center;
    }
    
    .title {
        font-size: 2.5rem;
    }
    
    .upload-area {
        padding: 40px 20px;
    }
    
    .upload-icon {
        font-size: 3rem;
    }
    
    .upload-area h3 {
        font-size: 1.5rem;
    }
    
    .preview-image {
        width: 250px;
        height: 250px;
    }
    
    .result-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .download-btn, .new-generation-btn {
        width: 100%;
        max-width: 250px;
    }
    
    .progress-container {
        padding: 30px 20px;
    }
    
    .progress-steps {
        flex-wrap: wrap;
        gap: 20px;
    }
    
    .step {
        flex: 1;
        min-width: 80px;
    }
    
    .step-icon {
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }
    
    .step-text {
        font-size: 0.8rem;
    }
    
    .history-header {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .history-container {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 15px;
    }
    
    .history-item {
        padding: 10px;
    }
    
    .history-item img {
        height: 120px;
    }
    
    .history-item-actions {
        flex-direction: column;
        gap: 5px;
    }
    
    .history-item-btn {
        padding: 6px 12px;
        font-size: 0.7rem;
    }
    
    .sample-item {
        flex-direction: column;
        gap: 20px;
    }
    
    .sample-before img, .sample-after img {
        width: 150px;
        height: 225px;
    }
    
    .sample-arrow {
        transform: rotate(90deg);
    }
    
    .sample-features {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .feature-item {
        padding: 15px;
    }
    
    .ad-container {
        padding: 15px;
    }
    
    .ad-content {
        min-height: 60px;
    }
    
    .about-header h2 {
        font-size: 1.8rem;
    }
    
    .about-main h3,
    .about-comparison h3,
    .about-use-cases h3,
    .about-technology h3 {
        font-size: 1.4rem;
    }
    
    .about-features {
        grid-template-columns: 1fr;
    }
    
    .comparison-table {
        font-size: 0.9rem;
    }
    
    .comparison-item {
        padding: 15px 10px;
    }
    
    .use-cases-grid {
        grid-template-columns: 1fr;
    }
    
    .about-technology {
        padding: 20px;
    }
    
    .about-link, .home-link, .share-btn {
        margin-right: 10px;
        padding: 10px 20px;
        font-size: 0.9rem;
    }
    
    .header-right {
        display: flex;
        flex-direction: row;
        gap: 10px;
        align-items: center;
        justify-content: center;
    }
    
    .about-cta {
        padding: 30px 20px;
    }
    
    .about-cta h3 {
        font-size: 1.5rem;
    }
    
    .about-cta p {
        font-size: 1.1rem;
    }
    
    .cta-btn {
        padding: 15px 30px;
        font-size: 1.1rem;
    }
    
    .article-content h2 {
        font-size: 1.8rem;
    }
    
    .article-content h3 {
        font-size: 1.5rem;
    }
    
    .feature-cards,
    .step-cards,
    .tip-cards,
    .use-case-cards {
        grid-template-columns: 1fr;
    }
    
    .feature-card,
    .step-card,
    .tip-card,
    .use-case-card {
        padding: 20px;
    }
    
    .highlight-box {
        padding: 20px;
    }
    
    .conclusion-section {
        padding: 30px 20px;
    }
}

@media (max-width: 480px) {
    .title {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .upload-area {
        padding: 30px 15px;
    }
    
    .upload-icon {
        font-size: 2.5rem;
    }
    
    .upload-area h3 {
        font-size: 1.3rem;
    }
    
    .generate-btn {
        padding: 15px 30px;
        font-size: 1.1rem;
        min-width: 200px;
    }
    
    .about-link, .home-link, .share-btn {
        padding: 8px 16px;
        font-size: 0.8rem;
        margin-right: 0;
    }
    
    .header-right {
        gap: 8px;
        flex-direction: row;
        justify-content: center;
    }
}

/* カスタムスクロールバー */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: var(--primary-gradient);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #5a67d8 0%, #6b46c1 100%);
}