/* Language Switcher */
.lang-switcher {
    position: fixed;
    top: 12px;
    right: 12px;
    z-index: 9999;
    background: #3FA63C;
    color: white;
    border: none;
    border-radius: 20px;
    padding: 6px 14px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s, transform 0.2s;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
    font-family: inherit;
}
.lang-switcher:hover {
    background: #2D7E2E;
    transform: scale(1.05);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f8f8;
}

.container {
    max-width: 100%;
    margin: 0 auto;
    padding: 0 16px;
}

/* Header */
.header {
    background: #3FA63C;
    color: white;
    padding: 16px 0;
    box-shadow: 0 2px 8px rgba(255,107,53,0.2);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo h1 {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 2px;
}

.tagline {
    font-size: 12px;
    opacity: 0.9;
}

.nav {
    display: flex;
    gap: 8px;
}

.nav a {
    color: white;
    text-decoration: none;
    font-size: 13px;
    transition: background-color 0.3s;
    padding: 6px 10px;
    border-radius: 4px;
    white-space: nowrap;
}

.nav a:hover,
.nav a:active {
    background-color: rgba(255,255,255,0.2);
}

/* Hero Section */
.hero {
    background: white;
    padding: 30px 0;
    text-align: center;
    border-bottom: 1px solid #e5e7eb;
}

.hero h2 {
    font-size: 24px;
    color: #1f2937;
    margin-bottom: 10px;
}

.hero p {
    font-size: 14px;
    color: #6b7280;
}

/* Tutorial Sections */
.tutorial-section {
    padding: 30px 0;
    background: white;
}

.tutorial-section.alt {
    background: #f9fafb;
}

.section-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.step-number {
    font-size: 32px;
    font-weight: 700;
    color: #3FA63C;
    opacity: 0.4;
}

.section-header h3 {
    font-size: 20px;
    color: #1f2937;
    font-weight: 600;
}

.tutorial-content {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* Video Wrapper */
.video-wrapper {
    position: relative;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    width: 100%;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
}

.video-wrapper:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(0,0,0,0.2);
}

.video-wrapper:active {
    transform: translateY(0);
}

/* 视频播放器样式 */
.video-player {
    width: 100%;
    height: auto;
    display: block;
    background: #000;
    outline: none;
    max-height: 70vh;
    object-fit: contain;
}

/* 视频模态框 */
.video-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 9999;
    animation: fadeIn 0.3s ease;
}

.video-modal.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.video-modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(5px);
}

.video-modal-content {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    z-index: 10000;
}

.video-modal-close {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 44px;
    height: 44px;
    background: rgba(255, 255, 255, 0.2);
    border: none;
    border-radius: 50%;
    color: white;
    font-size: 32px;
    line-height: 1;
    cursor: pointer;
    z-index: 10001;
    transition: background 0.3s, transform 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    -webkit-tap-highlight-color: transparent;
}

.video-modal-close:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: rotate(90deg);
}

.video-modal-close:active {
    background: rgba(255, 255, 255, 0.4);
}

.video-modal-player {
    width: 100%;
    max-width: 900px;
    background: #000;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
}

.modal-video-player {
    width: 100%;
    height: auto;
    display: block;
    background: #000;
    outline: none;
}

/* 移动端视频模态框优化 */
@media (max-width: 767px) {
    .video-modal-content {
        padding: 0;
    }
    
    .video-modal-player {
        max-width: 100%;
        border-radius: 0;
        height: 100%;
        display: flex;
        align-items: center;
        justify-content: center;
    }
    
    .modal-video-player {
        max-height: 100vh;
        object-fit: contain;
    }
    
    .video-modal-close {
        top: 20px;
        right: 20px;
        width: 50px;
        height: 50px;
        font-size: 36px;
        background: rgba(0, 0, 0, 0.6);
    }
}

/* 移动端视频优化 */
@media (max-width: 767px) {
    .video-wrapper {
        margin: 0;
        border-radius: 8px;
    }
}

/* 视频链接样式 */
.video-link {
    margin-top: 10px;
    padding: 10px;
    background: #f0f9ff;
    border-radius: 6px;
    border-left: 3px solid #4A90E2;
}

.video-link a,
.play-video-btn {
    color: #4A90E2;
    text-decoration: none;
    font-size: 14px;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-weight: 500;
    transition: color 0.3s;
    cursor: pointer;
}

.video-link a:hover,
.video-link a:active,
.play-video-btn:hover,
.play-video-btn:active {
    color: #2563eb;
    text-decoration: underline;
}

/* 视频错误提示 */
.video-error {
    aspect-ratio: 16/9;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
    color: white;
    padding: 20px;
    text-align: center;
}

.video-error p {
    margin: 8px 0;
    font-size: 16px;
    font-weight: 600;
}

.video-error .error-msg {
    font-size: 14px;
    font-weight: 400;
    opacity: 0.9;
}

.video-placeholder {
    aspect-ratio: 16/9;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    cursor: pointer;
    transition: opacity 0.3;
    -webkit-tap-highlight-color: transparent;
}

.video-placeholder:active {
    opacity: 0.9;
}

.video-placeholder svg {
    filter: drop-shadow(0 4px 8px rgba(0,0,0,0.2));
}

.video-placeholder p {
    color: white;
    margin-top: 12px;
    font-size: 14px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

/* Tutorial Steps */
.tutorial-steps {
    background: white;
    padding: 20px;
    border-radius: 8px;
    border: 1px solid #e5e7eb;
}

.tutorial-steps h4 {
    font-size: 16px;
    color: #1f2937;
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 2px solid #3FA63C;
    font-weight: 600;
}

.tutorial-steps ol {
    list-style: none;
    counter-reset: step-counter;
}

.tutorial-steps ol li {
    counter-increment: step-counter;
    margin-bottom: 20px;
    position: relative;
    padding-left: 36px;
}

.tutorial-steps ol li::before {
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: 0;
    width: 24px;
    height: 24px;
    background: #3FA63C;
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 13px;
    flex-shrink: 0;
}

.tutorial-steps strong {
    display: block;
    color: #1f2937;
    margin-bottom: 6px;
    font-size: 15px;
}

.tutorial-steps p {
    color: #6b7280;
    line-height: 1.6;
    font-size: 14px;
}

.qr-code {
    margin-top: 12px;
}

.qr-placeholder {
    width: 120px;
    height: 120px;
    border: 2px dashed #d1d5db;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #9ca3af;
    font-size: 12px;
    border-radius: 8px;
}

/* Tips */
.tips {
    margin-top: 20px;
    padding: 14px;
    background: #FFF5F0;
    border-left: 3px solid #3FA63C;
    border-radius: 6px;
}

.tips strong {
    color: #2D7E2E;
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
}

.tips p, .tips ul {
    color: #8B4513;
    font-size: 13px;
}

.tips ul {
    list-style: none;
    padding-left: 0;
}

.tips ul li {
    padding-left: 16px;
    position: relative;
    margin-bottom: 6px;
}

.tips ul li::before {
    content: "•";
    position: absolute;
    left: 4px;
    color: #3FA63C;
}

/* FAQ Section */
.faq-section {
    padding: 30px 0;
    background: white;
}

.faq-section h3 {
    font-size: 20px;
    color: #1f2937;
    text-align: center;
    margin-bottom: 20px;
    font-weight: 600;
}

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

.faq-item {
    padding: 16px;
    background: #f9fafb;
    border-radius: 8px;
    border: 1px solid #e5e7eb;
    transition: background-color 0.3s;
}

.faq-item:active {
    background-color: #f3f4f6;
}

.faq-item h4 {
    color: #3FA63C;
    font-size: 15px;
    margin-bottom: 8px;
    font-weight: 600;
}

.faq-item p {
    color: #4b5563;
    line-height: 1.6;
    font-size: 14px;
}

/* Support Section */
.support-section {
    padding: 30px 0;
    background: linear-gradient(135deg, #3FA63C 0%, #5BBF52 100%);
    color: white;
    text-align: center;
}

.support-section h3 {
    font-size: 20px;
    margin-bottom: 10px;
    font-weight: 600;
}

.support-section > p {
    font-size: 14px;
    margin-bottom: 24px;
    opacity: 0.95;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.contact-item {
    background: rgba(255,255,255,0.15);
    padding: 16px;
    border-radius: 8px;
    backdrop-filter: blur(10px);
    text-align: left;
}

.contact-item strong {
    display: block;
    font-size: 15px;
    margin-bottom: 8px;
}

.contact-item p {
    font-size: 16px;
    margin-bottom: 6px;
    font-weight: 500;
}

.contact-item span {
    font-size: 12px;
    opacity: 0.85;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    text-align: center;
    padding: 20px 0;
}

.footer p {
    opacity: 0.7;
    font-size: 13px;
}

/* 平板和桌面端适配 */
@media (min-width: 768px) {
    .container {
        max-width: 750px;
        padding: 0 24px;
    }
    
    .logo h1 {
        font-size: 26px;
    }
    
    .nav {
        gap: 20px;
    }
    
    .nav a {
        font-size: 15px;
        padding: 8px 14px;
    }
    
    .hero {
        padding: 50px 0;
    }
    
    .hero h2 {
        font-size: 32px;
    }
    
    .hero p {
        font-size: 16px;
    }
    
    .tutorial-section {
        padding: 50px 0;
    }
    
    .section-header h3 {
        font-size: 26px;
    }
    
    .step-number {
        font-size: 42px;
    }
    
    .tutorial-content {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 30px;
    }
    
    .tutorial-steps {
        padding: 24px;
    }
    
    .faq-section {
        padding: 50px 0;
    }
    
    .faq-section h3 {
        font-size: 28px;
        margin-bottom: 30px;
    }
    
    .faq-list {
        max-width: 800px;
        margin: 0 auto;
    }
    
    .support-section {
        padding: 50px 0;
    }
    
    .support-section h3 {
        font-size: 28px;
    }
    
    .support-section > p {
        font-size: 16px;
        margin-bottom: 40px;
    }
    
    .contact-info {
        flex-direction: row;
        gap: 24px;
    }
}

@media (min-width: 1024px) {
    .container {
        max-width: 1000px;
    }
}