@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');
@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@300;400;500;600;700&display=swap');

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

:root {
    /* Modern OpenAI-inspired Color Palette */
    --bg-primary: #0d1117;
    --bg-secondary: #161b22;
    --bg-tertiary: #21262d;
    --bg-elevated: #30363d;
    --bg-overlay: rgba(13, 17, 23, 0.95);
    
    /* Neutral Colors */
    --neutral-50: #f6f8fa;
    --neutral-100: #f0f6fc;
    --neutral-200: #d0d7de;
    --neutral-300: #afb8c1;
    --neutral-400: #8b949e;
    --neutral-500: #6e7681;
    --neutral-600: #484f58;
    --neutral-700: #32383f;
    --neutral-800: #24292f;
    --neutral-900: #1c2128;
    
    /* Accent Colors */
    --accent-primary: #238636;
    --accent-secondary: #0969da;
    --accent-warning: #d1242f;
    --accent-info: #1f6feb;
    --accent-success: #1a7f37;
    
    /* Text Colors */
    --text-primary: #f0f6fc;
    --text-secondary: #8b949e;
    --text-tertiary: #6e7681;
    --text-link: #58a6ff;
    
    /* Geometric Accent */
    --geometric-primary: #0969da;
    --geometric-secondary: #238636;
    --geometric-accent: #da3633;
    
    /* Modern Shadows & Effects */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 10px 24px rgba(0, 0, 0, 0.2);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.25);
    
    /* Modern Gradients */
    --grad-primary: linear-gradient(135deg, #0d1117 0%, #161b22 100%);
    --grad-surface: linear-gradient(135deg, #21262d 0%, #30363d 100%);
    --grad-accent: linear-gradient(135deg, #0969da 0%, #238636 100%);
    
    /* Typography */
    --font-display: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', 'Monaco', 'Cascadia Code', monospace;
    
    /* Backward Compatibility Variables */
    --primary-color: var(--geometric-primary);
    --primary-hover: #0550ae;
    --danger-color: var(--accent-warning);
    --danger-hover: #a40e26;
    --success-color: var(--accent-success);
    --warning-color: #bf8700;
    --white: var(--text-primary);
    --gray-50: var(--neutral-50);
    --gray-100: var(--neutral-100);
    --gray-200: var(--neutral-200);
    --gray-300: var(--neutral-300);
    --gray-400: var(--neutral-400);
    --gray-500: var(--neutral-500);
    --gray-600: var(--neutral-600);
    --gray-700: var(--neutral-700);
    --gray-800: var(--neutral-800);
    --gray-900: var(--neutral-900);
}

body {
    font-family: var(--font-body);
    background: var(--bg-primary);
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(9, 105, 218, 0.03) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(35, 134, 54, 0.02) 0%, transparent 50%);
    min-height: 100vh;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    color: var(--text-primary);
    position: relative;
    overflow-x: hidden;
}

/* Modern Geometric Grid Pattern */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(var(--neutral-800) 1px, transparent 1px),
        linear-gradient(90deg, var(--neutral-800) 1px, transparent 1px),
        radial-gradient(circle at 50px 50px, rgba(9, 105, 218, 0.02) 2px, transparent 2px);
    background-size: 50px 50px, 50px 50px, 100px 100px;
    pointer-events: none;
    z-index: -1;
    opacity: 0.6;
}

/* Subtle Geometric Animation */
body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        linear-gradient(45deg, transparent 49%, rgba(9, 105, 218, 0.01) 50%, transparent 51%),
        linear-gradient(-45deg, transparent 49%, rgba(35, 134, 54, 0.01) 50%, transparent 51%);
    background-size: 200px 200px;
    animation: geometricShift 20s ease-in-out infinite;
    pointer-events: none;
    z-index: -1;
}

@keyframes geometricShift {
    0%, 100% { transform: translate(0, 0) rotate(0deg); opacity: 0.3; }
    50% { transform: translate(-10px, -10px) rotate(0.5deg); opacity: 0.6; }
}

.container {
    width: 100%;
    min-height: 100vh;
    background: var(--bg-overlay);
    backdrop-filter: blur(20px);
    border: 1px solid var(--neutral-800);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    position: relative;
    box-shadow: var(--shadow-xl);
}

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

.header {
    background: var(--grad-primary);
    padding: 32px 40px;
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--neutral-700);
    box-shadow: var(--shadow-lg);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    z-index: 1;
}

.header-title {
    text-align: left;
    position: relative;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* Modern Geometric Pattern */
.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        linear-gradient(45deg, transparent 40%, rgba(9, 105, 218, 0.03) 50%, transparent 60%),
        radial-gradient(circle at 25px 25px, rgba(35, 134, 54, 0.02) 1px, transparent 1px);
    background-size: 100px 100px, 50px 50px;
    animation: headerGeometry 25s linear infinite;
}

@keyframes headerGeometry {
    0% { background-position: 0 0, 0 0; }
    100% { background-position: 200px 200px, 100px 100px; }
}

h1 {
    color: var(--text-primary);
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 800;
    margin: 0;
    position: relative;
    z-index: 1;
    letter-spacing: -0.02em;
    text-transform: none;
}

.subtitle {
    color: var(--text-secondary);
    font-family: var(--font-body);
    font-size: 1.1rem;
    margin-top: 6px;
    font-weight: 400;
    position: relative;
    z-index: 1;
    letter-spacing: 0.01em;
    text-transform: none;
}

.main-content {
    flex: 1;
    padding: 40px;
}

.content-wrapper {
    display: flex;
    gap: 30px;
    height: calc(100vh - 200px);
    min-height: 600px;
}

.left-panel {
    flex: 2;
    display: flex;
    flex-direction: column;
    background: var(--bg-tertiary);
    border: 1px solid var(--neutral-700);
    border-radius: 16px;
    padding: 28px;
    backdrop-filter: blur(20px);
    position: relative;
    overflow-y: auto;
    overflow-x: hidden;
}

.right-panel {
    flex: 5;
    background: var(--bg-tertiary);
    border: 1px solid var(--neutral-700);
    border-radius: 16px;
    display: flex;
    flex-direction: column;
    padding: 32px;
    backdrop-filter: blur(20px);
    position: relative;
    overflow: hidden;
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--gray-100);
}

.placeholder {
    text-align: center;
    color: var(--gray-500);
}

.placeholder h3 {
    font-size: 1.25rem;
    margin-bottom: 8px;
    color: var(--gray-600);
}

.placeholder p {
    font-size: 0.875rem;
}

.company-details {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.detail-header {
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--gray-200);
}

.detail-header h2 {
    margin: 0;
    color: var(--text-primary);
    font-size: 1.75rem;
}

.detail-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.detail-row {
    display: flex;
    align-items: center;
    gap: 15px;
}

.detail-row label {
    font-weight: 600;
    color: var(--text-primary);
    min-width: 100px;
    margin: 0;
}

.detail-row span {
    color: var(--text-primary);
    font-size: 1.1rem;
}

.detail-actions {
    display: flex;
    gap: 15px;
    margin-top: auto;
    padding-top: 20px;
}

h2 {
    color: var(--text-primary);
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0;
    display: flex;
    align-items: center;
    gap: 12px;
    letter-spacing: -0.01em;
    position: relative;
}

h2::before {
    content: '';
    width: 6px;
    height: 6px;
    background: var(--geometric-primary);
    border-radius: 1px;
    transform: rotate(45deg);
}

h2::after {
    content: '';
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, var(--neutral-600), transparent);
}

.sites-grid {
    display: grid;
    gap: 16px;
    margin-bottom: 20px;
}

#sites-list {
    list-style: none;
    padding: 0;
    display: grid;
    gap: 12px;
}

.site-item {
    background: var(--bg-elevated);
    border: 1px solid var(--neutral-600);
    border-radius: 12px;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all 0.25s cubic-bezier(0.4, 0.0, 0.2, 1);
    position: relative;
    overflow: hidden;
    cursor: pointer;
    backdrop-filter: blur(20px);
}

.site-item:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    border-color: var(--geometric-primary);
    background: var(--bg-elevated);
}

.site-item.selected {
    border-color: var(--geometric-primary);
    background: var(--bg-elevated);
    box-shadow: var(--shadow-lg);
    position: relative;
}

.site-item.selected::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: var(--geometric-primary);
}

.site-info {
    display: flex;
    align-items: center;
    gap: 12px;
    position: relative;
    z-index: 1;
}

.site-icon {
    width: 44px;
    height: 44px;
    background: var(--geometric-primary);
    border: none;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--neutral-50);
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.1rem;
    position: relative;
    overflow: hidden;
}

.site-icon::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.1) 50%, transparent 70%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.site-item:hover .site-icon::before {
    opacity: 1;
}

.site-details {
    display: flex;
    flex-direction: column;
}

.site-name {
    font-family: var(--font-body);
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 4px;
    letter-spacing: -0.005em;
}

.site-url {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    text-decoration: none;
    transition: all 0.2s ease;
    position: relative;
}

.site-url::before {
    content: '↗';
    color: var(--geometric-primary);
    margin-right: 6px;
    font-weight: normal;
    font-size: 0.75rem;
}

.site-url:hover {
    color: var(--text-link);
}

.site-actions {
    display: flex;
    gap: 8px;
    position: relative;
    z-index: 1;
}

.btn {
    border: 1px solid transparent;
    border-radius: 8px;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.4, 0.0, 0.2, 1);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    position: relative;
    letter-spacing: 0.01em;
    backdrop-filter: blur(15px);
}

.btn-sm {
    padding: 8px 16px;
}

.btn-md {
    padding: 12px 24px;
    font-size: 1rem;
}

.btn-primary {
    background: var(--geometric-primary);
    border-color: var(--geometric-primary);
    color: var(--neutral-50);
}

.btn-primary:hover {
    background: #0550ae;
    border-color: #0550ae;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-danger {
    background: var(--accent-warning);
    border-color: var(--accent-warning);
    color: var(--neutral-50);
}

.btn-danger:hover {
    background: #a40e26;
    border-color: #a40e26;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-outline {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: var(--text-primary);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.5);
    color: var(--text-primary);
    transform: translateY(-1px);
}

.logout-btn {
    background: transparent !important;
    border: 1px solid rgba(255, 255, 255, 0.3) !important;
    color: var(--white) !important;
}

.logout-btn:hover {
    background: rgba(255, 255, 255, 0.1) !important;
    border-color: rgba(255, 255, 255, 0.5) !important;
    transform: translateY(-1px);
}

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(4px);
}

.modal-overlay.show {
    display: flex;
}

.modal {
    background: var(--cyber-bg-card);
    border: 1px solid rgba(6, 182, 212, 0.3);
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    box-shadow: var(--shadow-neon);
    backdrop-filter: blur(20px);
    animation: modalSlideIn 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    position: relative;
    overflow: hidden;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: scale(0.9) translateY(-20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.modal-header {
    padding: 24px 24px 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--gray-200);
    margin-bottom: 24px;
}

.modal-header h3 {
    margin: 0;
    font-family: var(--font-cyber);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 0.02em;
}

.modal-close {
    background: none;
    border: none;
    font-size: 24px;
    color: var(--gray-500);
    cursor: pointer;
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.modal-close:hover {
    background: var(--gray-100);
    color: var(--gray-700);
}

.modal-body {
    padding: 0 24px 24px 24px;
}

.modal-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
    margin-top: 24px;
}

.form-group {
    position: relative;
    z-index: 1;
}

.form-field {
    margin-bottom: 20px;
}

.form-field:last-child {
    margin-bottom: 0;
}

label {
    display: block;
    font-family: var(--font-ui);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 10px;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.02em;
    position: relative;
}

label::before {
    content: '▸ ';
    color: var(--neon-cyan);
    font-family: var(--font-cyber);
    opacity: 0.8;
}

.input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid rgba(6, 182, 212, 0.3);
    border-radius: 6px;
    font-size: 1rem;
    font-family: var(--font-ui);
    transition: all 0.25s cubic-bezier(0.4, 0.0, 0.2, 1);
    background: rgba(15, 23, 42, 0.6);
    color: var(--text-primary);
    backdrop-filter: blur(10px);
}

.input:focus {
    outline: none;
    border-color: var(--neon-cyan);
    background: rgba(15, 23, 42, 0.8);
    box-shadow: 
        0 0 0 2px rgba(6, 182, 212, 0.2),
        0 2px 8px rgba(0, 0, 0, 0.15);
}

.input::placeholder {
    color: var(--text-muted);
    font-style: italic;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--gray-500);
}

.empty-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 16px;
    border-radius: 50%;
    background: var(--gray-100);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--gray-400);
}

.empty-title {
    font-size: 1.125rem;
    font-weight: 500;
    color: var(--gray-600);
    margin-bottom: 8px;
}

.empty-description {
    font-size: 0.875rem;
    color: var(--gray-500);
}

.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid var(--white);
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 1s linear infinite;
}

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

.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 16px 20px;
    border-radius: 8px;
    color: var(--white);
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    transform: translateX(100%);
    transition: transform 0.3s ease;
}

.notification.show {
    transform: translateX(0);
}

.notification.success {
    background: var(--success-color);
}

.notification.error {
    background: var(--danger-color);
}

/* レスポンシブデザイン */
@media (max-width: 1024px) {
    .content-wrapper {
        flex-direction: column;
        height: auto;
        gap: 20px;
    }
    
    .left-panel, .right-panel {
        flex: none;
    }
    
    .right-panel {
        min-height: 300px;
    }
}

@media (max-width: 768px) {
    .container {
        min-height: 100vh;
    }
    
    .header {
        padding: 24px 20px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 16px;
        align-items: center;
    }
    
    .header-title {
        text-align: center;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .main-content {
        padding: 20px;
    }
    
    .left-panel, .right-panel {
        padding: 20px;
    }
    
    .site-item {
        padding: 16px;
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .site-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    .modal {
        width: 95%;
        margin: 0 auto;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.75rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .main-content {
        padding: 16px;
    }
    
    .header {
        padding: 20px 16px;
    }
    
    .left-panel, .right-panel {
        padding: 16px;
    }
    
    .btn-sm {
        padding: 6px 12px;
        font-size: 0.8rem;
    }
    
    .site-icon {
        width: 36px;
        height: 36px;
        font-size: 0.9rem;
    }
    
    .site-name {
        font-size: 1rem;
    }
}

/* ファイル管理セクション */
.file-management {
    margin-top: 30px;
    border-top: 2px solid var(--gray-200);
    padding-top: 30px;
}

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

.file-header h3 {
    margin: 0;
    font-size: 1.25rem;
    color: var(--text-primary);
}

.file-actions {
    display: flex;
    gap: 10px;
}

.file-list {
    max-height: 400px;
    overflow-y: auto;
    border: 1px solid var(--neutral-600);
    border-radius: 8px;
    background: var(--bg-elevated);
    backdrop-filter: blur(10px);
    position: relative;
}

.file-list::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        linear-gradient(45deg, transparent 49%, rgba(128, 0, 255, 0.02) 50%, transparent 51%);
    background-size: 15px 15px;
    animation: fileListPattern 4s linear infinite;
    pointer-events: none;
}

@keyframes fileListPattern {
    0% { background-position: 0 0; }
    100% { background-position: 30px 30px; }
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    border-bottom: 1px solid rgba(128, 0, 255, 0.1);
    transition: all 0.3s ease;
    position: relative;
    z-index: 1;
}

.file-item:last-child {
    border-bottom: none;
}

.file-item:hover {
    background: rgba(128, 0, 255, 0.1);
    border-left: 3px solid var(--neon-purple);
    padding-left: 13px;
    box-shadow: inset 0 0 10px rgba(128, 0, 255, 0.2);
}

.file-info {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
}

.folder-clickable {
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.folder-clickable:hover {
    border-radius: 6px;
}

.folder-child {
    border-left: 2px solid var(--gray-200);
}

.file-icon {
    font-size: 1.5rem;
    width: 32px;
    text-align: center;
}

.file-details {
    flex: 1;
}

.file-name {
    font-family: var(--font-ui);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 2px;
    text-shadow: 0 0 5px rgba(128, 0, 255, 0.3);
}

.file-meta {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-secondary);
    opacity: 0.8;
}

.empty-files {
    text-align: center;
    padding: 40px 20px;
    color: var(--gray-500);
}

.detail-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 2px solid var(--gray-200);
}

.detail-info {
    margin-bottom: 20px;
}

.btn-xs {
    padding: 4px 8px;
    font-size: 0.75rem;
    min-height: auto;
}

/* ダークモード対応 */
@media (prefers-color-scheme: dark) {
    :root {
        --gray-50: #111827;
        --gray-100: #1f2937;
        --gray-200: #374151;
        --gray-300: #4b5563;
        --gray-400: #6b7280;
        --gray-500: #9ca3af;
        --gray-600: #d1d5db;
        --gray-700: #e5e7eb;
        --gray-800: #f3f4f6;
        --gray-900: #f9fafb;
        --white: #1f2937;
    }
    
    body {
        background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
    }
    
    .container {
        background: var(--white);
        border: 1px solid var(--gray-200);
    }
}

/* 非アクティブサイト用スタイル */
.site-item.inactive {
    opacity: 0.7;
    background: var(--gray-50);
}

.site-item.inactive .site-name {
    color: var(--gray-600);
}

.site-url.disabled {
    color: var(--gray-400);
    text-decoration: none;
    pointer-events: none;
}

.status-indicator {
    margin-left: 8px;
    font-size: 0.8rem;
}

/* ドラッグ&ドロップスタイル */
.draggable-item {
    cursor: grab;
    user-select: none;
}

.draggable-item:active {
    cursor: grabbing;
}

.file-item.dragging {
    opacity: 0.5;
    transition: all 0.2s ease;
}

.file-item.drag-over {
    background-color: rgba(59, 130, 246, 0.1);
    border: 2px dashed var(--primary-color);
    border-radius: 6px;
    transform: scale(1.02);
    transition: all 0.2s ease;
}

.file-item.drag-over .file-info {
    background-color: rgba(59, 130, 246, 0.05);
    border-radius: 4px;
}

/* ルートドロップゾーン */
.root-drop-zone {
    position: fixed;
    top: 50%;
    left: 50%;
    width: 300px;
    height: 150px;
    margin-left: -150px;
    margin-top: -75px;
    background: var(--white);
    border: 3px dashed var(--gray-300);
    border-radius: 12px;
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
    pointer-events: none;
}

.root-drop-zone.visible {
    display: flex;
    pointer-events: auto;
}

.root-drop-zone.drag-over {
    border-color: var(--primary-color);
    background-color: rgba(59, 130, 246, 0.05);
    transform: scale(1.05);
}

.root-drop-zone .drop-message {
    text-align: center;
    padding: 20px;
    color: var(--gray-600);
    font-size: 1.1rem;
    font-weight: 500;
}

.root-drop-zone.drag-over .drop-message {
    color: var(--primary-color);
}

/* エレガント ホバー エフェクト */
.elegant-hover {
    transition: all 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.elegant-hover:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}