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

:root {
    --color-bg: #ffffff;
    --color-surface: #fafafa;
    --color-border: #e0e0e0;
    --color-text: #1a1a1a;
    --color-text-secondary: #666666;
    --color-text-tertiary: #999999;
    --color-primary: #000000;
    --color-error: #d32f2f;
    --color-success: #2e7d32;
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 32px;
    --spacing-xl: 48px;
}

/* 移动端适配 */
@media (max-width: 768px) {
    :root {
        --spacing-xs: 6px;
        --spacing-sm: 12px;
        --spacing-md: 16px;
        --spacing-lg: 24px;
        --spacing-xl: 32px;
    }
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    margin: 0;
    padding: 0;
}

/* 内测码验证弹窗 */
.auth-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    padding: var(--spacing-md);
}

.auth-modal {
    background: var(--color-bg);
    padding: var(--spacing-xl);
    max-width: 400px;
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.auth-modal h2 {
    font-size: 20px;
    font-weight: 500;
    margin: 0;
}

.auth-modal p {
    font-size: 14px;
    color: var(--color-text-secondary);
    margin: 0;
}

.auth-modal input {
    width: 100%;
    padding: var(--spacing-sm);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    font-family: inherit;
    font-size: 14px;
    color: var(--color-text);
    box-sizing: border-box;
}

.auth-modal input:focus {
    outline: none;
    border-color: var(--color-primary);
}

.error-message {
    font-size: 13px;
    color: var(--color-error);
    text-align: center;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-md);
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
}

h1 {
    font-size: 24px;
    font-weight: 500;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 18px;
    font-weight: 500;
    letter-spacing: -0.01em;
}

.status {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 13px;
    color: var(--color-text-secondary);
}

.status .dot {
    width: 8px;
    height: 8px;
    background: var(--color-text-tertiary);
    display: block;
}

.status.online .dot {
    background: var(--color-success);
}

.status.offline .dot {
    background: var(--color-error);
}

main {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

label {
    font-size: 14px;
    font-weight: 500;
    color: var(--color-text);
}

.upload-area {
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    padding: var(--spacing-xl);
    cursor: pointer;
    transition: border-color 0.2s;
}

.upload-area:hover {
    border-color: var(--color-text-secondary);
}

.upload-area.dragover {
    border-color: var(--color-primary);
    background: var(--color-bg);
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--color-text-secondary);
}

.upload-content svg {
    color: var(--color-text-tertiary);
}

.upload-content p {
    font-size: 14px;
}

.hint {
    font-size: 12px;
    color: var(--color-text-tertiary);
}

.preview-area {
    position: relative;
    border: 1px solid var(--color-border);
    background: var(--color-surface);
}

.preview-area img {
    width: 100%;
    height: auto;
    display: block;
}

.preview-area .btn-text {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    background: var(--color-bg);
    border: 1px solid var(--color-border);
}

textarea {
    width: 100%;
    padding: var(--spacing-sm);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    font-family: inherit;
    font-size: 14px;
    color: var(--color-text);
    resize: vertical;
    min-height: 120px;
    transition: border-color 0.2s;
}

textarea:focus {
    outline: none;
    border-color: var(--color-primary);
}

textarea::placeholder {
    color: var(--color-text-tertiary);
}

.btn-primary {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--color-primary);
    color: var(--color-bg);
    border: none;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: opacity 0.2s;
    position: relative;
}

.btn-primary:hover:not(:disabled) {
    opacity: 0.85;
}

.btn-primary:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-primary .btn-text,
.btn-primary .btn-loading {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.btn-text {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: transparent;
    border: none;
    font-size: 13px;
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: color 0.2s;
}

.btn-text:hover {
    color: var(--color-text);
}

.spinner {
    width: 14px;
    height: 14px;
    border: 2px solid var(--color-bg);
    border-top-color: transparent;
    animation: spin 0.8s linear infinite;
    display: inline-block;
}

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

.result-section {
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-border);
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.result-image {
    border: 1px solid var(--color-border);
    background: var(--color-surface);
}

.result-image img {
    width: 100%;
    height: auto;
    display: block;
}

.hidden {
    display: none !important;
}

@media (max-width: 640px) {
    .container {
        padding: var(--spacing-md) var(--spacing-sm);
    }
    
    header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    h1 {
        font-size: 20px;
    }
    
    .upload-area {
        padding: var(--spacing-lg);
    }
    
    .upload-content svg {
        width: 36px;
        height: 36px;
    }
    
    .upload-content p {
        font-size: 13px;
    }
    
    textarea {
        font-size: 16px; /* 防止iOS自动缩放 */
        min-height: 100px;
    }
    
    .btn-primary {
        padding: var(--spacing-md);
        font-size: 16px;
    }
    
    .result-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .auth-modal {
        padding: var(--spacing-lg);
    }
    
    .auth-modal h2 {
        font-size: 18px;
    }
}

/* 移动端触摸优化 */
@media (hover: none) and (pointer: coarse) {
    .btn-primary,
    .btn-text,
    .upload-area {
        -webkit-tap-highlight-color: transparent;
    }
    
    .btn-primary:active {
        opacity: 0.7;
    }
    
    .btn-text:active {
        opacity: 0.7;
    }
}