/* main.css - 主样式文件 */
/* 宇宙星空超能力主题 */

@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

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

:root {
    --primary-gradient: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
    --accent-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    --glow-color: rgba(102, 126, 234, 0.6);
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.8);
    --text-muted: rgba(255, 255, 255, 0.6);
    --card-bg: rgba(255, 255, 255, 0.08);
    --card-border: rgba(255, 255, 255, 0.15);
    --gold-accent: #ffd700;
    
    /* Logo尺寸变量 - 圆的直径 */
    --logo-circle-size: 140px;
    /* 方形图片边长 = 圆直径 / √2 ≈ 圆直径 × 0.7071 */
    --logo-image-size: calc(var(--logo-circle-size) / 1.4142);
}

body {
    font-family: 'Noto Sans SC', 'Microsoft YaHei', 'PingFang SC', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--primary-gradient);
    min-height: 100vh;
    padding: 20px;
    position: relative;
    overflow-x: hidden;
}

/* 星空背景效果 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, rgba(255,255,255,0.8), transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.6), transparent),
        radial-gradient(1px 1px at 90px 40px, rgba(255,255,255,0.9), transparent),
        radial-gradient(2px 2px at 130px 80px, rgba(255,255,255,0.7), transparent),
        radial-gradient(1px 1px at 160px 120px, rgba(255,255,255,0.5), transparent),
        radial-gradient(2px 2px at 200px 50px, rgba(255,255,255,0.8), transparent),
        radial-gradient(1px 1px at 250px 160px, rgba(255,255,255,0.6), transparent),
        radial-gradient(2px 2px at 300px 100px, rgba(255,255,255,0.7), transparent);
    background-repeat: repeat;
    background-size: 350px 200px;
    animation: twinkle 8s ease-in-out infinite alternate;
    pointer-events: none;
    z-index: 0;
}

@keyframes twinkle {
    0%, 100% { opacity: 0.8; }
    50% { opacity: 1; }
}

/* 流动光效 */
body::after {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(ellipse at center, 
        rgba(102, 126, 234, 0.1) 0%, 
        transparent 50%);
    animation: aurora 15s ease-in-out infinite;
    pointer-events: none;
    z-index: 0;
}

@keyframes aurora {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    33% { transform: translate(30px, -30px) rotate(120deg); }
    66% { transform: translate(-20px, 20px) rotate(240deg); }
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 24px;
    border: 1px solid var(--card-border);
    box-shadow: 
        0 25px 50px -12px rgba(0, 0, 0, 0.5),
        0 0 60px rgba(102, 126, 234, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.1);
    overflow: hidden;
    position: relative;
    z-index: 1;
}

.header {
    background: linear-gradient(135deg, 
        rgba(102, 126, 234, 0.4) 0%, 
        rgba(118, 75, 162, 0.4) 50%,
        rgba(240, 147, 251, 0.3) 100%);
    text-align: center;
    padding: 50px 30px;
    position: relative;
    overflow: hidden;
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url("data:image/svg+xml,%3Csvg viewBox='0 0 400 400' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
    opacity: 0.03;
    pointer-events: none;
}

.header h1 {
    font-size: 2.8em;
    font-weight: 700;
    margin-bottom: 12px;
    text-shadow: 0 0 30px rgba(102, 126, 234, 0.8);
    letter-spacing: 3px;
    position: relative;
}

.header p {
    font-size: 1.3em;
    color: var(--text-secondary);
    font-weight: 300;
    letter-spacing: 2px;
}

.main-content {
    padding: 50px 40px;
}

.intro-section {
    text-align: center;
    margin-bottom: 50px;
}

/* ===== Logo 容器样式 ===== */
.logo-container {
    width: var(--logo-circle-size);
    height: var(--logo-circle-size);
    background: var(--accent-gradient);
    border-radius: 50%;
    margin: 0 auto 35px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 
        0 0 40px rgba(102, 126, 234, 0.5),
        0 0 80px rgba(118, 75, 162, 0.3),
        inset 0 -5px 20px rgba(0, 0, 0, 0.2);
    animation: pulse-glow 3s ease-in-out infinite;
    position: relative;
    overflow: hidden;
}

/* 外发光效果 */
.logo-container::before {
    content: '';
    position: absolute;
    inset: -3px;
    border-radius: 50%;
    background: var(--accent-gradient);
    z-index: -1;
    filter: blur(15px);
    opacity: 0.6;
}

/* Logo 图片样式 */
.logo-image {
    width: var(--logo-image-size);
    height: var(--logo-image-size);
    object-fit: contain;
    /* 让方形图片以对角线契合圆形 */
    transform: rotate(0deg);
    transition: transform 0.5s ease;
    filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.3));
}

/* 悬浮时的微旋转效果 */
.logo-container:hover .logo-image {
    transform: rotate(5deg) scale(1.05);
}

@keyframes pulse-glow {
    0%, 100% {
        box-shadow: 
            0 0 40px rgba(102, 126, 234, 0.5),
            0 0 80px rgba(118, 75, 162, 0.3);
        transform: scale(1);
    }
    50% {
        box-shadow: 
            0 0 60px rgba(102, 126, 234, 0.7),
            0 0 100px rgba(118, 75, 162, 0.5);
        transform: scale(1.02);
    }
}

/* 兼容旧的 logo-placeholder 样式（如果其他页面还在使用） */
.logo-placeholder {
    width: var(--logo-circle-size);
    height: var(--logo-circle-size);
    background: var(--accent-gradient);
    border-radius: 50%;
    margin: 0 auto 35px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3.5em;
    box-shadow: 
        0 0 40px rgba(102, 126, 234, 0.5),
        0 0 80px rgba(118, 75, 162, 0.3),
        inset 0 -5px 20px rgba(0, 0, 0, 0.2);
    animation: pulse-glow 3s ease-in-out infinite;
    position: relative;
}

.logo-placeholder::before {
    content: '';
    position: absolute;
    inset: -3px;
    border-radius: 50%;
    background: var(--accent-gradient);
    z-index: -1;
    filter: blur(15px);
    opacity: 0.6;
}

.intro-text h2 {
    color: var(--text-primary);
    margin-bottom: 20px;
    font-size: 1.9em;
    font-weight: 600;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.intro-text p {
    color: var(--text-secondary);
    font-size: 1.1em;
    line-height: 2;
    max-width: 600px;
    margin: 0 auto;
}

.start-section {
    text-align: center;
}

.start-btn {
    background: var(--accent-gradient);
    background-size: 200% 200%;
    color: white;
    border: none;
    padding: 18px 55px;
    font-size: 1.4em;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    margin-bottom: 25px;
    box-shadow: 
        0 10px 30px rgba(102, 126, 234, 0.4),
        0 0 40px rgba(102, 126, 234, 0.2);
    position: relative;
    overflow: hidden;
    letter-spacing: 2px;
}

.start-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(255, 255, 255, 0.3), 
        transparent);
    transition: left 0.5s ease;
}

.start-btn:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 
        0 15px 40px rgba(102, 126, 234, 0.5),
        0 0 60px rgba(102, 126, 234, 0.3);
    background-position: right center;
}

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

.start-btn:active {
    transform: translateY(-2px) scale(1);
}

.start-btn.clicked {
    animation: button-click 0.3s ease;
}

@keyframes button-click {
    0% { transform: scale(1); }
    50% { transform: scale(0.95); }
    100% { transform: scale(1); }
}

.disclaimer {
    color: var(--text-muted);
    font-size: 0.95em;
    padding: 15px 20px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.08);
    display: inline-block;
}

.footer {
    background: rgba(0, 0, 0, 0.2);
    text-align: center;
    padding: 25px;
    color: var(--text-muted);
    border-top: 1px solid var(--card-border);
    font-size: 0.9em;
    letter-spacing: 1px;
}

/* ===== 响应式设计 ===== */
@media (max-width: 768px) {
    :root {
        --logo-circle-size: 110px;
    }
    
    body {
        padding: 12px;
    }
    
    .container {
        border-radius: 20px;
    }
    
    .header {
        padding: 35px 20px;
    }
    
    .header h1 {
        font-size: 2em;
        letter-spacing: 2px;
    }
    
    .header p {
        font-size: 1.1em;
    }
    
    .main-content {
        padding: 35px 20px;
    }
    
    .logo-placeholder {
        font-size: 2.8em;
    }
    
    .intro-text h2 {
        font-size: 1.5em;
    }
    
    .intro-text p {
        font-size: 1em;
    }
    
    .start-btn {
        padding: 16px 40px;
        font-size: 1.2em;
    }
}

@media (max-width: 480px) {
    :root {
        --logo-circle-size: 90px;
    }
    
    .header h1 {
        font-size: 1.7em;
    }
    
    .logo-placeholder {
        font-size: 2.2em;
    }
    
    .intro-text h2 {
        font-size: 1.3em;
    }
    
    .start-btn {
        padding: 14px 35px;
        font-size: 1.1em;
        width: 100%;
        max-width: 280px;
    }
}