/* ============================================================
   语际点歌台 - 公用样式（两页共享）
   ============================================================ */

/* ========== 1. CSS 变量 ========== */
:root {
    --primary-100: #e0e8ff;
    --primary-200: #c1d0ff;
    --primary-300: #a2b9ff;
    --primary-400: #83a1ff;
    --primary-500: #6489ff;
    --primary-600: #4571ff;
    --primary-700: #2659ff;
    --primary-800: #0741ff;
    --primary-900: #0033d6;

    --accent-100: #fff0e6;
    --accent-200: #ffd9c2;
    --accent-300: #ffc299;
    --accent-400: #ffab70;
    --accent-500: #ff9447;
    --accent-600: #ff7d1e;

    --neutral-50: #f9fafb;
    --neutral-100: #f3f4f6;
    --neutral-200: #e5e7eb;
    --neutral-300: #d1d5db;
    --neutral-400: #9ca3af;
    --neutral-500: #6b7280;
    --neutral-600: #4b5563;
    --neutral-700: #374151;
    --neutral-800: #1f2937;
    --neutral-900: #111827;

    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 60px;

    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.02), 0 1px 2px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.04), 0 2px 4px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.06), 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1), 0 8px 10px rgba(0, 0, 0, 0.08);

    --transition-default: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========== 2. 全局重置 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: "Inter", "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
    line-height: 1.8;
    background: linear-gradient(120deg, var(--neutral-50), var(--primary-100));
    background-image:
        radial-gradient(rgba(100, 137, 255, 0.05) 1px, transparent 1px),
        radial-gradient(rgba(100, 137, 255, 0.03) 1px, transparent 1px);
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
    color: var(--neutral-800);
    padding: 20px 0;
    -webkit-tap-highlight-color: rgba(100, 137, 255, 0.1);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

/* ========== 3. 容器卡片 ========== */
.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 40px 30px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg), 0 0 0 1px rgba(100, 137, 255, 0.08);
    width: 95%;
    background: linear-gradient(180deg, #ffffff 0%, var(--neutral-50) 100%);
    border: 1px solid rgba(255, 255, 255, 0.8);
    position: relative;
    overflow: hidden;
}

.container::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 6px;
    background: linear-gradient(90deg, var(--primary-800), var(--accent-600));
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

/* ========== 4. 标题 ========== */
h1 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 24px;
    position: relative;
    line-height: 1.3;
    font-weight: 700;
    background: linear-gradient(90deg, var(--primary-800), var(--primary-600));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    letter-spacing: 0.5px;
}

h1::after {
    content: "";
    display: block;
    width: 80px;
    height: 3px;
    margin: 16px auto 0;
    border-radius: 3px;
    background: linear-gradient(90deg, var(--primary-800), var(--primary-500));
    box-shadow: 0 2px 4px rgba(100, 137, 255, 0.2);
}

h2 {
    color: var(--primary-700);
    font-size: 24px;
    margin: 30px 0 16px;
    padding-left: 12px;
    border-left: 4px solid var(--primary-600);
    line-height: 1.3;
    font-weight: 600;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
}

h3 {
    color: var(--neutral-800);
    font-size: 18px;
    margin: 12px 0 10px;
    text-align: center;
    font-weight: 600;
}

/* ========== 5. 内容区域（基础） ========== */
.product-details {
    margin-top: 20px;
    font-size: 16px;
    line-height: 1.9;
    padding: 0 4px;
    color: var(--neutral-700);
}

.product-details p {
    margin-bottom: 12px;
}

/* ========== 6. 主按钮（首页 & 价格页共用） ========== */
.main-wechat-btn,
.back-home {
    margin: 40px 0;
    text-align: center;
    padding: 10px 0;
}

.main-wechat-btn a,
.back-home a {
    display: inline-block;
    padding: 24px 0;
    background: linear-gradient(90deg, var(--primary-800), var(--primary-600));
    box-shadow: var(--shadow-xl), inset 0 1px 0 rgba(255, 255, 255, 0.2);
    color: #fff !important;
    font-size: 22px;
    font-weight: 700;
    text-decoration: none;
    border-radius: var(--radius-xl);
    transition: var(--transition-default);
    cursor: pointer;
    letter-spacing: 4px;
    width: 100%;
    max-width: 420px;
    position: relative;
    overflow: hidden;
    text-transform: uppercase;
    font-family: "Inter", "Microsoft YaHei", sans-serif;
}

.main-wechat-btn a::before,
.back-home a::before {
    content: "";
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: all 0.8s ease;
}

.main-wechat-btn a:hover,
.back-home a:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(100, 137, 255, 0.3);
    background: linear-gradient(90deg, var(--primary-900), var(--primary-700));
    text-decoration: none !important;
}

.main-wechat-btn a:hover::before,
.back-home a:hover::before {
    left: 100%;
}

.main-wechat-btn a:active,
.back-home a:active {
    transform: translateY(2px);
    box-shadow: 0 6px 12px rgba(100, 137, 255, 0.2);
}

.main-wechat-btn a:active::after,
.back-home a:active::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    animation: ripple 0.6s ease-out;
}

@keyframes ripple {
    to {
        width: 400px;
        height: 400px;
        opacity: 0;
    }
}

/* ========== 7. 版权 ========== */
.copyright {
    text-align: center;
    margin-top: 35px;
    padding-top: 20px;
    color: var(--neutral-500);
    font-size: 14px;
    line-height: 1.8;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
    border-top: 1px solid var(--neutral-200);
}

/* ========== 8. 响应式（公用部分） ========== */

@media (max-width: 768px) {
    .container {
        padding: 30px 20px;
        width: 96%;
    }

    h1 {
        font-size: 30px;
        margin-bottom: 20px;
    }

    h1::after {
        width: 70px;
        height: 2.5px;
    }

    h2 {
        font-size: 22px;
        margin: 25px 0 14px;
    }

    .product-details {
        font-size: 15px;
    }
}

@media (max-width: 480px) {
    body {
        padding: 15px 0;
    }

    .container {
        padding: 25px 15px;
        width: 98%;
    }

    h1 {
        font-size: 26px;
    }

    h1::after {
        width: 60px;
        height: 2px;
    }
}