:root {
    --color-bg: #f5f5f7;
    --color-surface: #ffffff;
    --color-label: #1d1d1f;
    --color-secondary: #6e6e73;
    --color-tertiary: #86868b;
    --color-accent: #007aff;
    --color-accent-hover: #0071e3;
    --color-accent-light: rgba(0, 122, 255, 0.08);
    --color-success: #34c759;
    --color-success-bg: rgba(52, 199, 89, 0.1);
    --color-warning: #ff9500;
    --color-warning-bg: rgba(255, 149, 0, 0.1);
    --color-error: #ff3b30;
    --color-error-bg: rgba(255, 59, 48, 0.08);
    --color-separator: rgba(60, 60, 67, 0.12);
    --color-fill-secondary: rgba(120, 120, 128, 0.12);
    --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", system-ui, sans-serif;
    --font-mono: ui-monospace, "SF Mono", "Cascadia Code", monospace;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.06), 0 4px 16px rgba(0, 0, 0, 0.04);
    --space-page: 24px;
    --max-width: 680px;
}

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

body {
    font-family: var(--font-sans);
    background: var(--color-bg);
    min-height: 100vh;
    color: var(--color-label);
    font-size: 15px;
    line-height: 1.47;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-page);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    text-align: center;
    margin-bottom: 32px;
}

.header h1 {
    color: var(--color-label);
    font-size: 28px;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 24px;
}

.progress-bar {
    display: flex;
    gap: 4px;
    margin: 0 auto;
    max-width: 320px;
}

.progress-segment {
    flex: 1;
    height: 4px;
    border-radius: 2px;
    background: var(--color-fill-secondary);
    transition: background 0.25s ease;
}

.progress-segment.completed {
    background: var(--color-accent);
}

.progress-segment.active {
    background: var(--color-accent);
    opacity: 0.45;
}

.content {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    padding: 32px;
    box-shadow: var(--shadow-card);
    flex: 1;
    margin-bottom: 20px;
    border: 1px solid var(--color-separator);
}

.content h2 {
    text-align: center;
    margin-bottom: 8px;
    color: var(--color-label);
    font-size: 22px;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.description {
    text-align: center;
    margin-bottom: 32px;
    color: var(--color-secondary);
    font-size: 13px;
}

.options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 8px;
}

.option-card {
    background: var(--color-surface);
    border: 1px solid var(--color-separator);
    border-radius: var(--radius-md);
    padding: 24px 20px;
    text-align: center;
    cursor: pointer;
    transition: border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.option-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-card);
}

.option-card.selected {
    border-color: var(--color-accent);
    background: var(--color-accent-light);
    box-shadow: 0 0 0 1px var(--color-accent);
}

.option-icon {
    margin-bottom: 16px;
    display: flex;
    justify-content: center;
    color: var(--color-accent);
}

.option-card h3 {
    margin-bottom: 8px;
    color: var(--color-label);
    font-size: 17px;
    font-weight: 600;
}

.option-card p {
    color: var(--color-secondary);
    font-size: 13px;
    line-height: 1.47;
}

.footer {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

.btn {
    padding: 11px 22px;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 500;
    font-family: var(--font-sans);
    cursor: pointer;
    transition: background 0.2s ease, opacity 0.2s ease;
}

.btn:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

.btn-primary {
    background: var(--color-accent);
    color: #fff;
}

.btn-primary:hover:not(:disabled) {
    background: var(--color-accent-hover);
}

.btn-primary:disabled {
    background: var(--color-fill-secondary);
    color: var(--color-tertiary);
    cursor: not-allowed;
}

.btn-secondary {
    background: var(--color-fill-secondary);
    color: var(--color-label);
}

.btn-secondary:hover {
    background: rgba(120, 120, 128, 0.2);
}

.placeholder-content {
    text-align: center;
    padding: 24px 8px;
}

.placeholder-icon {
    margin-bottom: 20px;
    display: flex;
    justify-content: center;
    color: var(--color-tertiary);
}

.placeholder-content h2 {
    margin-bottom: 8px;
}

.info-box,
.warning-box,
.success-box,
.error-box {
    padding: 16px;
    margin: 24px 0;
    border-radius: var(--radius-sm);
    text-align: left;
    border: 1px solid var(--color-separator);
}

.info-box {
    background: var(--color-accent-light);
    border-color: rgba(0, 122, 255, 0.2);
}

.info-box h3,
.info-box h4 {
    color: var(--color-label);
    margin-bottom: 8px;
    font-size: 15px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
}

.info-box ul {
    margin-left: 20px;
    color: var(--color-secondary);
}

.info-box li {
    margin-bottom: 6px;
}

.info-box p {
    color: var(--color-label);
}

.warning-box {
    background: var(--color-warning-bg);
    border-color: rgba(255, 149, 0, 0.25);
}

.warning-box h3,
.warning-box h4 {
    color: var(--color-label);
    margin-bottom: 8px;
    font-size: 15px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
}

.warning-box p {
    color: var(--color-label);
}

.success-box {
    background: var(--color-success-bg);
    border-color: rgba(52, 199, 89, 0.25);
}

.success-box h3 {
    color: var(--color-label);
    margin-bottom: 12px;
    font-size: 17px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
}

.success-box p {
    color: var(--color-secondary);
    margin-bottom: 8px;
}

.error-box {
    background: var(--color-error-bg);
    border-color: rgba(255, 59, 48, 0.2);
}

.error-box h3 {
    color: var(--color-label);
    margin-bottom: 12px;
    font-size: 17px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
}

.error-box p {
    color: var(--color-secondary);
}

.instruction-steps {
    margin: 8px 0;
    border: 1px solid var(--color-separator);
    border-radius: var(--radius-md);
    overflow: hidden;
    background: var(--color-surface);
}

.step {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 0;
    padding: 20px;
    background: transparent;
    border-radius: 0;
    border: none;
    border-bottom: 1px solid var(--color-separator);
}

.step:last-child {
    border-bottom: none;
}

.step-number {
    background: transparent;
    color: var(--color-accent);
    border: 1.5px solid var(--color-accent);
    width: 26px;
    height: 26px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 13px;
    font-variant-numeric: tabular-nums;
    margin-right: 0;
    flex-shrink: 0;
    line-height: 1;
}

.step-content {
    flex: 1;
    min-width: 0;
}

.step-content h3 {
    margin-bottom: 6px;
    color: var(--color-label);
    font-size: 17px;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.step-content p {
    color: var(--color-label);
    line-height: 1.5;
    margin-bottom: 8px;
}

.step-content ul {
    margin-left: 18px;
    color: var(--color-label);
}

.step-content li {
    margin-bottom: 6px;
    line-height: 1.5;
}

.step-content li::marker {
    color: var(--color-accent);
}

.url-box {
    background: var(--color-surface);
    border: 1px solid var(--color-separator);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    margin: 12px 0;
    text-align: center;
    font-family: var(--font-mono);
    font-size: 14px;
    color: var(--color-label);
}

.highlight-box {
    background: var(--color-accent-light);
    border: 1px solid rgba(0, 122, 255, 0.2);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    margin: 10px 0;
    text-align: left;
    font-weight: 500;
    color: var(--color-label);
    font-size: 14px;
}

.critical-warning {
    background: var(--color-error-bg);
    border: 1px solid rgba(255, 59, 48, 0.25);
    border-radius: var(--radius-sm);
    padding: 16px;
    margin: 12px 0;
    text-align: left;
}

.critical-warning h4 {
    color: var(--color-error);
    margin-bottom: 8px;
    font-size: 15px;
    font-weight: 600;
}

.critical-warning p {
    color: var(--color-secondary);
    margin-bottom: 6px;
    font-weight: 500;
}

.auth-box {
    background: var(--color-surface);
    border: 1px solid var(--color-separator);
    border-radius: var(--radius-sm);
    padding: 16px;
    margin: 12px 0;
}

.auth-item {
    margin-bottom: 8px;
    font-size: 15px;
    color: var(--color-label);
}

.auth-item:last-child {
    margin-bottom: 0;
}

.highlight {
    background: var(--color-warning-bg);
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 500;
    color: var(--color-label);
}

.navigation-path {
    background: var(--color-surface);
    border: 1px solid var(--color-separator);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    margin: 12px 0;
    text-align: center;
    font-size: 15px;
    color: var(--color-label);
}

.data-form {
    max-width: 100%;
    margin: 0 auto;
    padding: 0;
    background: transparent;
    border-radius: 0;
    box-shadow: none;
}

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

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    color: var(--color-label);
    font-size: 15px;
}

.form-group input {
    width: 100%;
    padding: 11px 14px;
    border: 1px solid var(--color-separator);
    border-radius: 10px;
    font-size: 15px;
    font-family: var(--font-sans);
    background: var(--color-surface);
    color: var(--color-label);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.15);
}

.form-group input:invalid:not(:placeholder-shown) {
    border-color: var(--color-error);
}

.form-help {
    display: block;
    margin-top: 6px;
    color: var(--color-secondary);
    font-size: 13px;
    line-height: 1.47;
}

.password-hint {
    background: var(--color-warning-bg);
    border: 1px solid rgba(255, 149, 0, 0.2);
    border-radius: var(--radius-sm);
    padding: 10px 12px;
    margin-top: 8px;
    color: var(--color-secondary);
    font-size: 13px;
}

.form-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin-top: 28px;
}

.form-actions .btn {
    min-width: 120px;
}

.check-steps {
    margin: 8px 0;
}

.check-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 12px;
    padding: 20px;
    background: var(--color-surface);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-separator);
    transition: background 0.2s ease, border-color 0.2s ease;
}

.check-item.loading {
    border-color: rgba(255, 149, 0, 0.3);
    background: var(--color-warning-bg);
}

.check-item.success {
    border-color: rgba(52, 199, 89, 0.3);
    background: var(--color-success-bg);
}

.check-item.error {
    border-color: rgba(255, 59, 48, 0.25);
    background: var(--color-error-bg);
}

.check-icon {
    margin-right: 16px;
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-secondary);
}

.check-item.success .check-icon {
    color: var(--color-success);
}

.check-item.error .check-icon {
    color: var(--color-error);
}

.check-item.loading .check-icon {
    color: var(--color-warning);
}

.check-content {
    flex: 1;
}

.check-content h3 {
    margin-bottom: 4px;
    color: var(--color-label);
    font-size: 17px;
    font-weight: 600;
}

.check-content p {
    color: var(--color-label);
    margin-bottom: 12px;
    line-height: 1.5;
    font-size: 15px;
}

.check-status {
    padding: 4px 12px;
    border-radius: 20px;
    font-weight: 500;
    font-size: 13px;
    display: inline-block;
}

.check-status.loading {
    background: var(--color-warning-bg);
    color: var(--color-label);
    border: 1px solid rgba(255, 149, 0, 0.2);
}

.check-status.success {
    background: var(--color-success-bg);
    color: var(--color-label);
    border: 1px solid rgba(52, 199, 89, 0.25);
}

.check-status.error {
    background: var(--color-error-bg);
    color: var(--color-label);
    border: 1px solid rgba(255, 59, 48, 0.2);
}

.btn-retry {
    background: var(--color-fill-secondary);
    color: var(--color-label);
    border: none;
    padding: 6px 14px;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 500;
    font-family: var(--font-sans);
    cursor: pointer;
    transition: background 0.2s ease;
    margin-top: 10px;
}

.btn-retry:hover {
    background: rgba(120, 120, 128, 0.2);
}

.btn-retry:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

.icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

.icon-lg {
    width: 40px;
    height: 40px;
}

.icon-spin {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.box-title {
    display: flex;
    align-items: center;
    gap: 8px;
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 16px;
    }

    .header h1 {
        font-size: 24px;
    }

    .content {
        padding: 20px;
    }

    .options {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .step {
        flex-direction: row;
        padding: 16px;
    }

    .step-number {
        margin-bottom: 0;
    }

    .footer {
        flex-direction: column-reverse;
        align-items: stretch;
    }

    .footer .btn {
        width: 100%;
    }

    .form-actions {
        flex-direction: column-reverse;
    }

    .form-actions .btn {
        width: 100%;
    }
}