/* ==================== 基础样式 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2c5282;
    --secondary-color: #2d3748;
    --success-color: #2f855a;
    --error-color: #c53030;
    --warning-color: #d69e2e;
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --bg-white: #ffffff;
    --bg-light: #f7fafc;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-image: url('https://bing.img.run/rand.php');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    background-repeat: no-repeat;
    min-height: 100vh;
    color: var(--text-primary);
    line-height: 1.6;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 0;
}

/* ==================== 页面包装器 ==================== */
.page-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
    position: relative;
    z-index: 1;
}

/* ==================== 主卡片 ==================== */
.main-card {
    background: var(--bg-white);
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    padding: 40px;
    width: 100%;
    max-width: 520px;
    position: relative;
    z-index: 1;
}

/* ==================== 卡片头部 ==================== */
.card-header {
    text-align: center;
    margin-bottom: 32px;
}

.logo {
    width: 56px;
    height: 56px;
    margin: 0 auto 20px;
    background: var(--primary-color);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo svg {
    width: 32px;
    height: 32px;
    color: white;
}

.card-header h1 {
    font-size: 24px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.subtitle {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 400;
}

/* ==================== 公告区域 ==================== */
.announcements {
    margin-bottom: 28px;
    padding: 16px;
    background: #fefce8;
    border-radius: 4px;
    border: 1px solid #fde047;
}

.announcements-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    font-weight: 600;
    color: #854d0e;
    font-size: 14px;
}

.announcement-icon {
    width: 18px;
    height: 18px;
}

.announcements-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.announcement-item {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    font-size: 14px;
    color: #713f12;
    line-height: 1.5;
}

.announcement-dot {
    width: 6px;
    height: 6px;
    background: #ca8a04;
    border-radius: 50%;
    margin-top: 7px;
    flex-shrink: 0;
}

.announcement-text {
    flex: 1;
}

/* ==================== 表单样式 ==================== */
.shorten-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.form-group {
}

label {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 14px;
}

.input-icon {
    width: 18px;
    height: 18px;
    color: var(--text-secondary);
}

.input-wrapper {
    position: relative;
}

input[type="text"],
input[type="url"] {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 14px;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
    font-family: inherit;
    background: var(--bg-white);
    color: var(--text-primary);
}

input[type="text"]::placeholder,
input[type="url"]::placeholder {
    color: var(--text-muted);
}

input[type="text"]:hover,
input[type="url"]:hover {
    border-color: #cbd5e0;
}

input[type="text"]:focus,
input[type="url"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(44, 82, 130, 0.1);
}

input[readonly] {
    background-color: var(--bg-light);
    cursor: text;
}

.hint {
    display: flex;
    align-items: flex-start;
    gap: 6px;
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: 8px;
    line-height: 1.4;
}

.hint-icon {
    width: 14px;
    height: 14px;
    flex-shrink: 0;
    margin-top: 1px;
    color: var(--text-muted);
}

/* ==================== Turnstile 样式 ==================== */
.turnstile-container {
    margin: 8px 0;
    display: flex;
    justify-content: center;
}

/* ==================== 按钮样式 ==================== */
button[type="submit"] {
    width: 100%;
    padding: 12px 24px;
    border: 1px solid transparent;
    border-radius: 4px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
    font-family: inherit;
    background: var(--primary-color);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-top: 8px;
}

button[type="submit"]:hover:not(:disabled) {
    background: #2b6cb0;
}

button[type="submit"]:active:not(:disabled) {
    background: #2c5282;
}

button[type="submit"]:disabled {
    opacity: 0.65;
    cursor: not-allowed;
    background: #718096;
}

button[type="submit"].loading {
    pointer-events: none;
}

button[type="submit"].loading .btn-icon {
    animation: spin 1s linear infinite;
}

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

.btn-icon {
    width: 18px;
    height: 18px;
}

/* ==================== 错误信息样式 ==================== */
.error-message {
    display: none;
    align-items: center;
    gap: 10px;
    background: #fff5f5;
    color: #742a2a;
    padding: 12px 16px;
    border-radius: 4px;
    margin-top: 20px;
    font-size: 14px;
    border: 1px solid #fc8181;
}

.error-message.show {
    display: flex;
}

.error-message.turnstile-error {
    background: #fffbeb;
    color: #92400e;
    border-color: #f59e0b;
}

.error-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    color: var(--error-color);
}

/* ==================== 字段错误提示样式 ==================== */
.form-group.has-error input {
    border-color: #ef4444;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.form-group.has-error input:focus {
    border-color: #ef4444;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.2);
}

.field-error-tip {
    display: none;
    align-items: center;
    gap: 6px;
    margin-top: 8px;
    font-size: 13px;
    color: #dc2626;
    font-weight: 500;
}

.field-error-tip::before {
    content: '';
    display: inline-block;
    width: 14px;
    height: 14px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23dc2626' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='12' cy='12' r='10'/%3E%3Cline x1='12' y1='8' x2='12' y2='12'/%3E%3Cline x1='12' y1='16' x2='12.01' y2='16'/%3E%3C/svg%3E");
    background-size: contain;
    background-repeat: no-repeat;
    flex-shrink: 0;
}

/* ==================== 页脚样式 ==================== */
.page-footer {
    text-align: center;
    color: rgba(255, 255, 255, 0.9);
    font-size: 13px;
    padding: 24px;
    position: relative;
    z-index: 1;
}

/* ==================== 容器样式 (兼容旧版) ==================== */
.container {
    background: var(--bg-white);
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    padding: 40px;
    width: 100%;
    max-width: 500px;
    margin-bottom: 20px;
}

/* ==================== 标题样式 (兼容旧版) ==================== */
h1 {
    text-align: center;
    color: var(--text-primary);
    margin-bottom: 24px;
    font-size: 24px;
    font-weight: 600;
}

/* ==================== 按钮样式 (兼容旧版) ==================== */
.btn-primary,
.btn-secondary {
    display: inline-block;
    padding: 10px 20px;
    border: 1px solid transparent;
    border-radius: 4px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out;
    text-align: center;
    text-decoration: none;
    font-family: inherit;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: #2b6cb0;
}

.btn-secondary {
    background: var(--bg-light);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: #e2e8f0;
    color: var(--text-primary);
}

.copy-btn {
    padding: 10px 16px;
    background: var(--primary-color);
    color: white;
    border: 1px solid transparent;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
    min-height: 44px;
    box-shadow: 0 2px 4px 0 rgba(44, 82, 130, 0.15);
}

.copy-btn:hover {
    background: #2b6cb0;
    transform: translateY(-1px);
    box-shadow: 0 4px 8px 0 rgba(44, 82, 130, 0.25);
}

.copy-btn:active {
    transform: translateY(0);
    box-shadow: 0 2px 4px 0 rgba(44, 82, 130, 0.15);
}

.copy-btn.copied {
    background: #10b981;
}

.copy-btn svg {
    width: 20px;
    height: 20px;
}

/* ==================== 结果页面样式 ==================== */
.result-card {
    background: var(--bg-light);
    border-radius: 4px;
    padding: 20px;
    margin-bottom: 20px;
    border: 1px solid var(--border-color);
}

.result-item {
    margin-bottom: 16px;
}

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

.result-item label {
    font-size: 12px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
    font-weight: 500;
}

.result-value {
    display: flex;
    align-items: center;
    gap: 10px;
}

.result-value input {
    flex: 1;
    font-size: 14px;
}

.code-badge {
    display: inline-block;
    padding: 8px 16px;
    background: var(--primary-color);
    color: white;
    border-radius: 4px;
    font-weight: 500;
    font-size: 14px;
}

.long-url a {
    color: var(--primary-color);
    text-decoration: none;
    word-break: break-all;
    font-size: 14px;
    transition: color 0.15s ease-in-out;
}

.long-url a:hover {
    color: #2b6cb0;
    text-decoration: underline;
}

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

.actions .btn-primary,
.actions .btn-secondary {
    flex: 1;
}

.copy-message {
    position: fixed;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    background: #1a202c;
    color: white;
    padding: 10px 20px;
    border-radius: 4px;
    font-size: 13px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s ease-in-out;
    z-index: 1000;
    box-shadow: var(--shadow-md);
}

.copy-message.show {
    opacity: 1;
    visibility: visible;
}

/* ==================== 404 错误页面样式 ==================== */
.error-page {
    text-align: center;
    padding: 20px 0;
}

.error-code {
    font-size: 96px;
    font-weight: 700;
    color: var(--primary-color);
    line-height: 1;
    margin-bottom: 16px;
}

.error-page h1 {
    margin-bottom: 12px;
}

.error-page .error-message {
    display: block;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 16px;
    margin-bottom: 24px;
}

.error-actions {
    margin-top: 24px;
}

/* ==================== 页脚样式 (兼容旧版) ==================== */
.footer {
    text-align: center;
    color: rgba(255, 255, 255, 0.9);
    font-size: 13px;
    padding: 20px;
}

.footer p {
    margin: 0;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 640px) {
    .page-wrapper {
        padding: 16px;
    }
    
    .main-card {
        padding: 24px;
        border-radius: 6px;
    }
    
    .card-header h1 {
        font-size: 20px;
    }
    
    .subtitle {
        font-size: 13px;
    }
    
    .logo {
        width: 48px;
        height: 48px;
    }
    
    .logo svg {
        width: 28px;
        height: 28px;
    }
    
    .announcements {
        padding: 12px;
    }
    
    input[type="text"],
    input[type="url"] {
        padding: 10px 14px;
        font-size: 16px;
    }
    
    button[type="submit"] {
        padding: 10px 20px;
    }
}

@media (max-width: 480px) {
    .main-card {
        padding: 20px;
    }
    
    .card-header h1 {
        font-size: 18px;
    }
    
    .container {
        padding: 20px;
        border-radius: 6px;
    }
    
    h1 {
        font-size: 20px;
        margin-bottom: 20px;
    }
    
    .error-code {
        font-size: 72px;
    }
    
    .result-value {
        flex-direction: column;
        align-items: stretch;
    }
    
    .copy-btn {
        width: 100%;
    }
    
    .actions {
        flex-direction: column;
    }
    
    .actions .btn-primary,
    .actions .btn-secondary {
        width: 100%;
    }
    
    .result-card {
        padding: 16px;
    }
}

@media (max-width: 360px) {
    .main-card {
        padding: 16px;
    }
    
    .card-header h1 {
        font-size: 16px;
    }
    
    .subtitle {
        font-size: 12px;
    }
}

/* ==================== 辅助类 ==================== */
.text-center {
    text-align: center;
}

.mt-20 {
    margin-top: 20px;
}

.mb-20 {
    margin-bottom: 20px;
}

/* ==================== 深色模式支持 ==================== */
@media (prefers-color-scheme: dark) {
    :root {
        --text-primary: #f7fafc;
        --text-secondary: #cbd5e0;
        --text-muted: #a0aec0;
        --bg-white: #2d3748;
        --bg-light: #1a202c;
        --border-color: #4a5568;
    }
    
    .main-card {
        background: #2d3748;
    }
    
    input[type="text"],
    input[type="url"] {
        background: #1a202c;
        border-color: #4a5568;
        color: #f7fafc;
    }
    
    input[type="text"]::placeholder,
    input[type="url"]::placeholder {
        color: #718096;
    }
    
    input[type="text"]:hover,
    input[type="url"]:hover {
        border-color: #718096;
    }
    
    .result-card {
        background: #1a202c;
    }
    
    .btn-secondary {
        background: #4a5568;
        border-color: #718096;
        color: #cbd5e0;
    }
    
    .btn-secondary:hover {
        background: #718096;
        border-color: #a0aec0;
        color: #f7fafc;
    }
    
    .error-message {
        background: #742a2a;
        border-color: #c53030;
        color: #feb2b2;
    }
}

/* ==================== 教程页面样式 ==================== */
.main-card:has(.tutorial-header) {
    max-width: 950px;
    padding: 56px 48px;
    background: linear-gradient(145deg, rgba(255,255,255,0.98) 0%, rgba(248,250,252,0.95) 100%);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255,255,255,0.8);
}

.tutorial-header {
    text-align: center;
    margin-bottom: 40px;
    position: relative;
}

.tutorial-header::before {
    content: '';
    position: absolute;
    top: -20px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, transparent 0%, #667eea 50%, transparent 100%);
    border-radius: 2px;
}

.tutorial-logo {
    width: 80px;
    height: 80px;
    margin: 0 auto 28px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 20px 40px -10px rgba(102, 126, 234, 0.4);
    animation: pulse-glow 3s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% {
        box-shadow: 0 20px 40px -10px rgba(102, 126, 234, 0.4);
    }
    50% {
        box-shadow: 0 20px 60px -10px rgba(102, 126, 234, 0.6);
    }
}

.tutorial-logo svg {
    width: 44px;
    height: 44px;
    color: white;
}

.tutorial-header h1 {
    font-size: 32px;
    font-weight: 800;
    color: #000000;
    margin-bottom: 12px;
    background: linear-gradient(135deg, #1a202c 0%, #2d3748 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tutorial-header .subtitle {
    font-size: 16px;
    color: #4a5568;
    font-weight: 500;
}

.tutorial-nav {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 48px;
    background: linear-gradient(145deg, #f7fafc 0%, #edf2f7 100%);
    padding: 10px;
    border-radius: 16px;
    border: 1px solid #e2e8f0;
}

.nav-tab {
    flex: 1;
    padding: 14px 24px;
    border: none;
    background: transparent;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 700;
    color: #4a5568;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.nav-tab::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.4) 50%, transparent 100%);
    transition: left 0.5s ease;
}

.nav-tab:hover {
    color: #2d3748;
    background: rgba(255,255,255,0.7);
}

.nav-tab:hover::before {
    left: 100%;
}

.nav-tab.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 10px 30px -10px rgba(102, 126, 234, 0.5);
}

.section-title {
    text-align: center;
    margin-bottom: 44px;
    position: relative;
}

.section-title h2 {
    font-size: 26px;
    font-weight: 800;
    color: #000000;
    margin-bottom: 16px;
    background: linear-gradient(135deg, #1a202c 0%, #2d3748 50%, #4a5568 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.title-line {
    width: 80px;
    height: 5px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    margin: 0 auto;
    border-radius: 3px;
    box-shadow: 0 4px 15px -5px rgba(102, 126, 234, 0.4);
}

.steps-container {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.step-card {
    background: linear-gradient(145deg, #ffffff 0%, #fafafa 100%);
    padding: 32px 28px;
    border-radius: 20px;
    border: 1px solid #e8e8e8;
    position: relative;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 20px -8px rgba(0,0,0,0.08);
}

.step-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 5px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.step-card::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(102,126,234,0.05) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 0.4s ease;
    pointer-events: none;
}

.step-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 25px 50px -15px rgba(0, 0, 0, 0.15);
    border-color: #667eea;
}

.step-card:hover::before {
    opacity: 1;
}

.step-card:hover::after {
    opacity: 1;
}

.step-number-wrapper {
    position: absolute;
    top: 24px;
    right: 24px;
}

.step-number {
    display: inline-block;
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 6px 20px -6px rgba(102, 126, 234, 0.5);
}

.step-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 100%);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: #667eea;
    box-shadow: 0 4px 15px -6px rgba(102, 126, 234, 0.2);
    transition: all 0.4s ease;
}

.step-card:hover .step-icon {
    transform: scale(1.1) rotate(5deg);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 8px 25px -8px rgba(102, 126, 234, 0.4);
}

.step-icon svg {
    width: 28px;
    height: 28px;
}

.step-card h3 {
    font-size: 18px;
    font-weight: 800;
    color: #000000;
    margin-bottom: 12px;
}

.step-card p {
    font-size: 14px;
    color: #4a5568;
    line-height: 1.7;
    margin: 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: linear-gradient(145deg, #ffffff 0%, #fafafa 100%);
    padding: 32px 28px;
    border-radius: 20px;
    border: 1px solid #e8e8e8;
    text-align: center;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    box-shadow: 0 4px 20px -8px rgba(0,0,0,0.08);
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 5px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.feature-card:hover {
    transform: translateY(-8px) scale(1.03);
    box-shadow: 0 25px 50px -15px rgba(0, 0, 0, 0.15);
    border-color: #667eea;
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-icon-wrapper {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    color: white;
    box-shadow: 0 12px 30px -10px rgba(102, 126, 234, 0.5);
    transition: all 0.4s ease;
}

.feature-card:hover .feature-icon-wrapper {
    transform: scale(1.15) rotate(10deg);
    box-shadow: 0 16px 40px -12px rgba(102, 126, 234, 0.6);
}

.feature-icon-wrapper svg {
    width: 32px;
    height: 32px;
}

.feature-card h3 {
    font-size: 17px;
    font-weight: 800;
    color: #000000;
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 14px;
    color: #4a5568;
    line-height: 1.7;
    margin: 0;
}

.faq-container {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.faq-item {
    background: #ffffff !important;
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 12px -6px rgba(0,0,0,0.05);
}

.faq-item:hover {
    border-color: #cbd5e0;
    box-shadow: 0 6px 20px -8px rgba(0,0,0,0.08);
}

.faq-item.open {
    border-color: #667eea;
    box-shadow: 0 10px 30px -10px rgba(102, 126, 234, 0.25);
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 22px 28px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 700;
    color: #1a202c !important;
    background: #ffffff !important;
    transition: all 0.3s ease;
}

.faq-question:hover {
    background: #f7fafc !important;
}

.faq-arrow {
    width: 24px;
    height: 24px;
    color: #718096 !important;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    flex-shrink: 0;
    margin-left: 16px;
}

.faq-item.open .faq-arrow {
    transform: rotate(180deg);
    color: #667eea !important;
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    background: #ffffff !important;
}

.faq-item.open .faq-answer {
    max-height: 400px;
}

.faq-answer p {
    padding: 0 28px 24px;
    font-size: 15px;
    color: #4a5568 !important;
    line-height: 1.8;
    margin: 0;
    background: #ffffff !important;
}

.tutorial-footer {
    text-align: center;
    margin-top: 48px;
    padding-top: 36px;
    border-top: 2px solid #e8e8e8;
    position: relative;
}

.tutorial-footer::before {
    content: '';
    position: absolute;
    top: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 2px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
}

.back-home-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 36px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    color: white;
    border-radius: 14px;
    text-decoration: none;
    font-size: 15px;
    font-weight: 700;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 8px 25px -10px rgba(102, 126, 234, 0.5);
    position: relative;
    overflow: hidden;
}

.back-home-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.3) 50%, transparent 100%);
    transition: left 0.6s ease;
}

.back-home-btn:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 16px 40px -12px rgba(102, 126, 234, 0.6);
}

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

.back-home-btn svg {
    width: 20px;
    height: 20px;
}

/* 教程页面响应式设计 */
@media (max-width: 768px) {
    .main-card:has(.tutorial-header) {
        padding: 40px 28px;
    }
    
    .tutorial-logo {
        width: 68px;
        height: 68px;
    }
    
    .tutorial-logo svg {
        width: 36px;
        height: 36px;
    }
    
    .tutorial-header h1 {
        font-size: 26px;
    }
    
    .steps-container {
        grid-template-columns: 1fr;
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .tutorial-nav {
        flex-wrap: wrap;
    }
    
    .nav-tab {
        flex: none;
        width: calc(50% - 4px);
    }
}

@media (max-width: 480px) {
    .main-card:has(.tutorial-header) {
        padding: 32px 24px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .nav-tab {
        width: 100%;
    }
    
    .step-card,
    .feature-card {
        padding: 28px 24px;
    }
    
    .faq-question {
        padding: 18px 22px;
        font-size: 15px;
    }
    
    .faq-answer p {
        padding: 0 22px 20px;
    }
    
    .section-title h2 {
        font-size: 22px;
    }
}

/* ==================== 首页教程链接样式 ==================== */
.tutorial-link-wrapper {
    margin-top: 28px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.tutorial-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 10px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px -4px rgba(102, 126, 234, 0.4);
}

.tutorial-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px -6px rgba(102, 126, 234, 0.5);
}

.tutorial-link svg {
    width: 18px;
    height: 18px;
}

@media (max-width: 640px) {
    .tutorial-link-wrapper {
        margin-top: 24px;
        padding-top: 20px;
    }
    
    .tutorial-link {
        padding: 8px 16px;
        font-size: 13px;
    }
}

/* ==================== 历史记录样式 ==================== */
.history-section {
    margin-top: 32px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.history-header h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.clear-history-btn {
    padding: 6px 12px;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 12px;
    color: var(--text-muted);
    cursor: pointer;
    transition: all 0.2s ease;
}

.clear-history-btn:hover {
    background: #fee2e2;
    border-color: #ef4444;
    color: #dc2626;
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.history-item {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    padding: 16px;
    background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
    border-radius: 10px;
    border: 1px solid #e2e8f0;
    transition: all 0.2s ease;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.history-item:hover {
    border-color: #cbd5e1;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    transform: translateY(-1px);
}

.history-info {
    display: flex;
    flex-direction: column;
    gap: 6px;
    flex: 1;
    min-width: 0;
}

.history-short-url {
    font-size: 15px;
    font-weight: 600;
    color: var(--primary-color);
    text-decoration: none;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    transition: color 0.2s ease;
}

.history-short-url:hover {
    text-decoration: underline;
    color: #1e40af;
}

.history-long-url {
    font-size: 12px;
    color: #64748b;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    background: white;
    padding: 4px 8px;
    border-radius: 4px;
    border: 1px solid #e2e8f0;
}

.history-actions {
    display: flex;
    gap: 8px;
    margin-left: 12px;
}

.history-copy-btn,
.history-visit-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    background: white;
    color: #64748b;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.history-copy-btn:hover,
.history-visit-btn:hover {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
    box-shadow: 0 4px 6px -1px rgba(44, 82, 130, 0.2);
    transform: translateY(-1px);
}

.history-copy-btn:active,
.history-visit-btn:active {
    transform: translateY(0);
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

@media (max-width: 640px) {
    .history-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .history-actions {
        margin-left: 0;
        width: 100%;
        justify-content: flex-end;
    }
}

/* ==================== SEO内容区域样式 ==================== */
.seo-content {
    margin-top: 40px;
    padding-top: 32px;
    border-top: 1px solid var(--border-color);
}

.content-section {
    margin-bottom: 32px;
}

.content-section:last-child {
    margin-bottom: 0;
}

.content-section h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 20px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--primary-color);
    display: inline-block;
}

/* 步骤样式 */
.steps {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.step {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 16px;
    background: var(--bg-light);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.step-number {
    width: 32px;
    height: 32px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
    flex-shrink: 0;
}

.step-content h3 {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.step-content p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin: 0;
}

/* 特性样式 */
.features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.feature {
    padding: 16px;
    background: var(--bg-light);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    text-align: center;
}

.feature-icon {
    font-size: 28px;
    margin-bottom: 8px;
}

.feature h3 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.feature p {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.4;
    margin: 0;
}

/* FAQ样式 */
.faq-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.faq-item {
    padding: 16px;
    background: var(--bg-light);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.faq-item h4 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.faq-item p {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin: 0;
}

/* SEO内容响应式设计 */
@media (max-width: 640px) {
    .seo-content {
        margin-top: 32px;
        padding-top: 24px;
    }
    
    .content-section h2 {
        font-size: 16px;
    }
    
    .features {
        grid-template-columns: 1fr;
    }
    
    .step {
        padding: 12px;
    }
    
    .feature {
        padding: 12px;
    }
    
    .faq-item {
        padding: 12px;
    }
}