:root {
    --primary-color: #FE2C55;
    --secondary-color: #25F4EE;
    --bg-color: #0F0F0F;
    --card-bg: #1A1A1A;
    --text-primary: #FFFFFF;
    --text-secondary: #A0A0A0;
    --accent-color: #FF6B6B;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--bg-color);
    min-height: 100vh;
}

.container {
    padding: 16px;
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
}

.app-title {
    text-align: center;
    font-size: 28px;
    margin: 40px 0 30px;
    color: var(--primary-color);
}

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

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 16px 24px;
    border-radius: 12px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    font-size: 16px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    min-height: 44px;
}

.btn:active {
    transform: scale(0.98);
}

.btn-icon {
    font-size: 24px;
}

.header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 24px;
    padding-top: 16px;
}

.back-btn {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 18px;
    cursor: pointer;
    padding: 8px;
    min-height: 44px;
}

.page-title {
    font-size: 22px;
    color: var(--primary-color);
}

.tag-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 24px;
}

.tag {
    padding: 10px 18px;
    background: var(--card-bg);
    border: 2px solid transparent;
    border-radius: 20px;
    color: var(--text-primary);
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
    min-height: 44px;
}

.tag.selected {
    background: var(--primary-color);
    border-color: var(--secondary-color);
}

.textbox-container {
    margin-bottom: 20px;
}

#textBox {
    width: 100%;
    min-height: 200px;
    padding: 16px;
    background: var(--card-bg);
    border: 1px solid #333;
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 15px;
    line-height: 1.6;
    resize: vertical;
}

.copy-btn {
    width: 100%;
}

.qianwen-btn {
    width: 100%;
    background: linear-gradient(135deg, #1E90FF, #4169E1);
    margin-top: 12px;
}

.tip {
    text-align: center;
    color: var(--secondary-color);
    margin-top: 16px;
    opacity: 0;
    transition: opacity 0.3s;
}

.tip.show {
    opacity: 1;
}

.video-container {
    margin-top: 20px;
}

#tutorialVideo {
    width: 100%;
    border-radius: 12px;
    background: #000;
}

@media (min-width: 768px) {
    .btn-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .container {
        max-width: 800px;
    }
}