:root {
    --neon-blue: #00f2ff;
    --panel-bg: rgba(0, 20, 40, 0.75);
    --sun-glow: 0 0 80px #ff6600;
}

body {
    margin: 0; background: #000; color: white;
    font-family: 'Segoe UI', sans-serif;
    overflow: hidden; height: 100vh;
    display: flex; justify-content: center; align-items: center;
}

/* خلفية النجوم */
#star-field { position: fixed; width: 100%; height: 100%; z-index: -1; }

/* النظام الشمسي */
.solar-system {
    position: relative; width: 100%; height: 100%;
    display: flex; justify-content: center; align-items: center;
    transform: scale(0.6);
}

/* تصميم الشمس وتوهجها */
.sun {
    width: 80px; height: 80px;
    background: radial-gradient(circle, #fff, #ffcc00, #ff4400);
    border-radius: 50%; box-shadow: var(--sun-glow);
    z-index: 100; cursor: pointer;
    animation: pulse 4s infinite alternate;
}

@keyframes pulse { from { transform: scale(1); } to { transform: scale(1.05); } }

/* تصميم المدارات الدائرية */
.orbit {
    position: absolute; border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 50%; animation: rotate linear infinite;
    pointer-events: none;
}

/* حاوية الكوكب لضمان موضعه الصحيح فوق المدار */
.planet-container {
    position: absolute; top: 0; left: 50%;
    transform: translateX(-50%) translateY(-50%);
    pointer-events: auto;
}

/* التنسيق المشترك لجميع الكواكب */
.planet {
    border-radius: 50%; cursor: pointer; transition: 0.3s;
    box-shadow: inset -5px -5px 15px rgba(0,0,0,0.8), inset 3px 3px 8px rgba(255,255,255,0.2);
}

.planet:hover { transform: scale(1.3); filter: brightness(1.2); }

/* خصائص كل كوكب (لون وحجم) */
.mercury { width: 14px; height: 14px; background: #888; }
.venus { width: 22px; height: 22px; background: #e3bb76; }
.earth { width: 26px; height: 26px; background: #1e90ff; }
.mars { width: 18px; height: 18px; background: #ff4500; }
.jupiter { width: 55px; height: 55px; background: #d3a567; }
.uranus { width: 34px; height: 34px; background: #afeeee; }
.neptune { width: 32px; height: 32px; background: #4169e1; }

/* كوكب زحل مع الحلقات */
.saturn { width: 45px; height: 45px; background: #e0cda9; position: relative; }
.saturn::after {
    content: ''; position: absolute; top: 50%; left: 50%;
    width: 80px; height: 15px; border: 3px solid rgba(194, 174, 126, 0.5);
    border-radius: 50%; transform: translate(-50%, -50%) rotateX(75deg);
}

/* أنيميشن الدوران */
@keyframes rotate { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }

/* تصميم اللوحة الجانبية العائمة */
#side-panel {
    position: fixed; 
    right: 30px; bottom: 30px; 
    width: 300px; 
    background: rgba(0, 15, 30, 0.85); 
    backdrop-filter: blur(20px); 
    border: 2px solid var(--neon-blue); 
    border-radius: 20px; 
    padding: 25px; 
    transition: all 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    z-index: 2000;
    box-shadow: 0 10px 40px rgba(0, 242, 255, 0.2); 
    opacity: 0;
    transform: translateY(20px) scale(0.9);
    pointer-events: none;
}

#side-panel.active { 
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: auto;
}

.planet-title { font-size: 1.8rem; color: var(--neon-blue); text-align: center; margin-bottom: 15px; }

.data-box {
    background: rgba(255, 255, 255, 0.05);
    padding: 10px 15px; border-radius: 12px; margin-bottom: 8px;
    border-right: 3px solid var(--neon-blue);
    display: flex; justify-content: space-between; align-items: center;
}

.label { font-size: 0.7rem; color: #888; }
.value { font-size: 0.95rem; color: #fff; font-weight: bold; }

.description { font-size: 0.85rem; line-height: 1.6; color: #ddd; background: rgba(0,0,0,0.3); padding: 10px; border-radius: 8px; }

.close-btn { 
    width: 100%; padding: 10px; cursor: pointer; border-radius: 10px;
    background: linear-gradient(90deg, transparent, rgba(0, 242, 255, 0.2), transparent);
    border: 1px solid var(--neon-blue); color: var(--neon-blue); font-weight: bold;
}
.close-btn:hover { background: var(--neon-blue); color: #000; }