/* =========================================
   Cyber Snow Pro UI (Ultimate Fix)
   ========================================= */
:root {
    --bg-deep: #0b1121;
    --card-glass: rgba(30, 41, 59, 0.8); /* 稍微加深不透明度，提升文字可读性 */
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-blue: #0ea5e9;
    --accent-red: #ef4444;
    --accent-gold: #f59e0b;
    --accent-green: #10b981;
    --nav-height: 70px;
    --radius-lg: 20px;
    --radius-sm: 12px;
}

body {
    background-color: var(--bg-deep);
    color: var(--text-primary);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background-image: 
        radial-gradient(circle at 0% 0%, rgba(14, 165, 233, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 100% 100%, rgba(245, 158, 11, 0.08) 0%, transparent 50%);
    background-attachment: fixed;
    /* 移除之前的 padding-bottom，改用物理占位 div 控制 */
    margin: 0;
    -webkit-tap-highlight-color: transparent;
}

/* 页面进入动画 */
.fade-in-up { animation: fadeInUp 0.4s ease-out forwards; }
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 玻璃卡片 */
.card {
    background: var(--card-glass) !important;
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(255, 255, 255, 0.08) !important;
    border-radius: var(--radius-lg) !important;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}
.card-header {
    background: rgba(255, 255, 255, 0.03) !important;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05) !important;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* 按钮优化 */
.btn {
    border-radius: var(--radius-sm);
    font-weight: 600;
    padding: 12px 20px;
    border: none;
    transition: all 0.2s;
}
.btn:active { transform: scale(0.95); }
.btn-primary { background: var(--accent-blue); color: #fff; box-shadow: 0 4px 15px rgba(14, 165, 233, 0.3); }
.btn-danger { background: var(--accent-red); color: #fff; box-shadow: 0 4px 15px rgba(239, 68, 68, 0.3); }
.btn-success { background: var(--accent-green); color: #fff; box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3); }
.btn-warning { background: var(--accent-gold); color: #000; box-shadow: 0 4px 15px rgba(245, 158, 11, 0.3); }
.btn-dark { background: rgba(15, 23, 42, 0.6); border: 1px solid rgba(255,255,255,0.2); color: var(--accent-blue); }

/* --- 底部悬浮导航栏 (增强版) --- */
.bottom-nav {
    position: fixed;
    /* 适配 iPhone 底部安全区 */
    bottom: calc(20px + env(safe-area-inset-bottom)); 
    left: 20px;
    right: 20px;
    height: var(--nav-height);
    background: rgba(15, 23, 42, 0.95); /* 更不透明，防止背景杂乱干扰 */
    backdrop-filter: blur(25px);
    -webkit-backdrop-filter: blur(25px);
    border-radius: 25px;
    border: 1px solid rgba(255,255,255,0.15);
    box-shadow: 0 15px 40px rgba(0,0,0,0.6);
    display: flex;
    justify-content: space-around;
    align-items: center;
    z-index: 9999;
    max-width: 500px;
    margin: 0 auto;
}
.nav-item-link {
    color: var(--text-secondary);
    text-decoration: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    font-size: 0.7rem; /* 稍微调小字体，避免换行 */
    width: 60px;
}
.nav-item-link.active { color: var(--accent-blue); }
.nav-item-link i { font-size: 1.4rem; margin-bottom: 2px; }

.nav-item-fab {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, #ef4444 0%, #f43f5e 100%);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    font-size: 1.8rem;
    margin-top: -40px;
    box-shadow: 0 8px 25px rgba(239, 68, 68, 0.5);
    border: 5px solid var(--bg-deep);
    transition: transform 0.2s;
}
.nav-item-fab:active { transform: scale(0.9); }

/* --- 全局底部物理占位符 --- */
.page-spacer {
    height: 140px; /* 强制撑开底部，高度 > 导航栏高度 */
    width: 100%;
    clear: both;
}

/* 控件 */
.text-muted { color: #94a3b8 !important; }
.form-control, .form-select {
    background: rgba(0,0,0,0.3) !important;
    border: 1px solid rgba(255,255,255,0.15) !important;
    color: #fff !important;
    padding: 14px;
    border-radius: 12px;
}
a { text-decoration: none; }