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

:root {
    /* Modern palette */
    --color-primary: #4F46E5; /* indigo-600 */
    --color-primary-hover: #4338CA; /* indigo-700 */
    --color-primary-soft: rgba(79, 70, 229, 0.15);

    --color-bg: #f8fafc; /* slate-50 */
    --color-surface: #ffffff;
    --color-border: #e5e7eb; /* gray-200 */

    --color-text: #111827; /* gray-900 */
    --color-subtle-text: #6b7280; /* gray-500 */

    --color-success: #10B981; /* emerald-500 */
    --color-success-soft: #ECFDF5;
    --color-error: #EF4444; /* red-500 */
    --color-error-soft: #FEF2F2;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--color-bg);
    min-height: 100vh;
    color: var(--color-text);
    position: relative;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    position: relative;
    z-index: 2;
}

.header {
    text-align: center;
    padding: 80px 0 60px;
    color: var(--color-text);
    position: relative;
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--color-primary);
    border-radius: 2px;
}

.logo {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--color-text);
    letter-spacing: -1px;
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.7;
    margin-bottom: 20px;
    font-weight: 400;
    color: var(--color-subtle-text);
}

.download-card {
    background: var(--color-surface);
    border-radius: 16px;
    padding: 50px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    margin: 40px 0;
    border: 1px solid var(--color-border);
    position: relative;
}

.download-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--color-primary);
}

.input-group {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
    flex-wrap: wrap;
    align-items: center;
}

.url-input {
    flex: 1;
    min-width: 300px;
    padding: 16px 20px;
    border: 2px solid var(--color-border);
    border-radius: 12px;
    font-size: 16px;
    transition: all 0.3s ease;
    outline: none;
    background: var(--color-surface);
}

.url-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.download-btn {
    padding: 16px 32px;
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.download-btn:hover {
    background: var(--color-primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px var(--color-primary-soft);
}

.download-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* 验证码样式 */
.cf-turnstile {
    margin-top: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 65px;
    padding: 15px;
    background: var(--color-bg);
    border-radius: 12px;
    border: 1px solid var(--color-border);
    position: relative;
}

.cf-turnstile iframe {
    border-radius: 8px;
    border: none;
    background: transparent;
    z-index: 2;
    position: relative;
}

/* 验证码加载状态 */
.cf-turnstile::before {
    content: '正在加载验证码...';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--color-subtle-text);
    font-size: 14px;
    opacity: 0.7;
    z-index: 1;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin: 60px 0;
}

.feature-card {
    background: var(--color-surface);
    padding: 40px 30px;
    border-radius: 16px;
    text-align: center;
    box-shadow: 0 8px 25px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    border: 1px solid var(--color-border);
    position: relative;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--color-primary);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 15px 35px rgba(0,0,0,0.12);
}

.feature-icon {
    font-size: 3.5rem;
    margin-bottom: 20px;
    color: var(--color-primary);
}

.feature-title {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: var(--color-text);
    letter-spacing: -0.5px;
}

.feature-desc {
    color: var(--color-subtle-text);
    line-height: 1.6;
}

.how-to {
    background: var(--color-surface);
    border-radius: 16px;
    padding: 50px;
    margin: 40px 0;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    border: 1px solid var(--color-border);
    position: relative;
}

.how-to::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--color-primary);
}

.how-to h2 {
    text-align: center;
    margin-bottom: 50px;
    color: var(--color-text);
    font-size: 2.2rem;
    font-weight: 600;
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
}

.step {
    text-align: center;
    padding: 20px;
}

.step-number {
    width: 50px;
    height: 50px;
    background: var(--color-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: bold;
    margin: 0 auto 20px;
}

.step-title {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--color-text);
    letter-spacing: -0.3px;
}

.step-desc {
    color: var(--color-subtle-text);
    line-height: 1.5;
}

.about-section {
    background: var(--color-surface);
    border-radius: 16px;
    padding: 40px;
    margin: 40px 0;
    box-shadow: 0 8px 25px rgba(0,0,0,0.08);
    border: 1px solid var(--color-border);
}

.about-section h2 {
    color: var(--color-text);
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 20px;
    text-align: center;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-top: 30px;
}

.about-item {
    padding: 20px;
    background: var(--color-bg);
    border-radius: 12px;
    border-left: 4px solid var(--color-primary);
}

.about-item h3 {
    color: var(--color-text);
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 15px;
}

.about-item p {
    color: var(--color-subtle-text);
    line-height: 1.6;
    margin-bottom: 10px;
}

.about-item ul {
    color: var(--color-subtle-text);
    line-height: 1.6;
    padding-left: 20px;
}

.about-item li {
    margin-bottom: 8px;
}

.footer {
    text-align: center;
    padding: 50px 0;
    color: var(--color-subtle-text);
    opacity: 0.8;
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 2px;
    background: var(--color-primary);
    border-radius: 1px;
}

.language-switcher {
    position: fixed;
    top: 30px;
    right: 30px;
    z-index: 1000;
}

.language-btn {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: 10px 14px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    color: var(--color-text);
}

.language-btn:hover {
    background: var(--color-bg);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
    transform: translateY(-1px);
}

.language-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
    display: none;
    min-width: 120px;
    margin-top: 5px;
    overflow: hidden;
}

.language-dropdown.show {
    display: block;
}

.language-option {
    padding: 10px 15px;
    cursor: pointer;
    transition: background 0.2s ease;
    border-bottom: 1px solid var(--color-border);
    font-weight: 400;
    color: var(--color-text);
}

.language-option:last-child {
    border-bottom: none;
}

.language-option:hover {
    background: var(--color-bg);
}

.language-option.active {
    background: var(--color-primary);
    color: white;
    font-weight: 500;
}

.loading {
    display: none;
    text-align: center;
    padding: 20px;
}

.spinner {
    border: 3px solid #f3f3f3;
    border-top: 3px solid var(--color-primary);
    border-radius: 50%;
    width: 30px;
    height: 30px;
    animation: spin 1s linear infinite;
    margin: 0 auto 15px;
}

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

.result {
    display: none;
    margin-top: 30px;
    padding: 20px;
    background: var(--color-bg);
    border-radius: 12px;
    border-left: 4px solid var(--color-primary);
}

.error {
    display: none;
    margin-top: 20px;
    padding: 15px;
    background: var(--color-error-soft);
    border: 1px solid rgba(239, 68, 68, 0.25);
    border-radius: 8px;
    color: var(--color-error);
}

.success {
    display: none;
    margin-top: 20px;
    padding: 15px;
    background: var(--color-success-soft);
    border: 1px solid rgba(16, 185, 129, 0.25);
    border-radius: 8px;
    color: var(--color-success);
}

/* 极简动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.header, .download-card, .features, .how-to {
    animation: fadeIn 0.6s ease-out;
}

@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .logo {
        font-size: 2.5rem;
    }
    
    .subtitle {
        font-size: 1.1rem;
    }
    
    .input-group {
        flex-direction: column;
        gap: 16px;
    }
    
    .url-input {
        min-width: auto;
        padding: 18px 22px;
        min-height: 52px;
        font-size: 17px;
    }
    
    .download-btn {
        width: 100%;
        min-height: 52px;
        padding: 18px 22px;
        font-size: 16px;
    }

    .download-card {
        padding: 30px 20px;
        margin: 20px 0;
    }
    
    .cf-turnstile {
        margin-top: 15px;
        min-height: 60px;
    }
    
    .features {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .feature-card {
        padding: 30px 20px;
    }
    
    .how-to {
        padding: 30px 20px;
    }
    
    .how-to h2 {
        font-size: 2rem;
    }
    
    .about-section {
        padding: 30px 20px;
    }
    
    .about-content {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .about-item {
        padding: 15px;
    }
    
    .language-switcher {
        top: 20px;
        right: 20px;
    }
    
    .language-btn {
        padding: 10px 14px;
        font-size: 13px;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 2rem;
    }
    
    .url-input {
        padding: 20px 22px;
        min-height: 56px;
        font-size: 18px;
    }

    .download-btn {
        min-height: 56px;
        padding: 20px 22px;
        font-size: 17px;
    }

    .download-card {
        padding: 25px 15px;
    }
    
    .feature-card {
        padding: 25px 15px;
    }
    
    .how-to {
        padding: 25px 15px;
    }


} 


.qa-section {
    padding: 3rem;
    background: var(--color-surface);
    border-radius: 12px;
    margin: 3rem auto;
    max-width: 1200px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.qa-section h2 {
    text-align: center;
    margin-bottom: 3rem;
    color: var(--color-text);
    font-size: 2rem;
    font-weight: 600;
}

.qa-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: 2rem;
}

.qa-item {
    background: var(--color-bg);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
}

.qa-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.qa-item h3 {
    color: var(--color-primary);
    margin-bottom: 1rem;
    font-size: 1.4rem;
    font-weight: 500;
    position: relative;
    padding-left: 1.5rem;
}

.qa-item h3:before {
    content: "Q:";
    position: absolute;
    left: 0;
    color: var(--color-primary);
}

.qa-item p {
    color: var(--color-subtle-text);
    line-height: 1.8;
    font-size: 1.1rem;
    padding-left: 1.5rem;
}

@media (max-width: 768px) {
    .qa-content {
        grid-template-columns: 1fr;
    }
    
    .qa-section {
        padding: 2rem;
        margin: 2rem 1rem;
    }
}