/* =============================================================================
 * style.css · 太阳系引力演示
 * ========================================================================== */
:root{
  --bg:#04060d;
  --panel:rgba(10,16,30,.78);
  --panel-line:rgba(120,170,255,.16);
  --txt:#dce6f7;
  --dim:#8fa2c0;
  --accent:#6cc6ff;
  --accent2:#ffb457;
  --warn:#ff7a6c;
  --ok:#7ee0a8;
}
*{box-sizing:border-box}
html,body{margin:0;height:100%;overflow:hidden;background:var(--bg);color:var(--txt);
  font-family:"PingFang SC","Microsoft YaHei","Hiragino Sans GB","Source Han Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
  -webkit-font-smoothing:antialiased;}
#scene{position:fixed;inset:0;width:100%;height:100%;display:block;cursor:grab;touch-action:none}
#scene.dragging{cursor:grabbing}

/* ---- 星球名称标签 ---- */
#labels{position:fixed;inset:0;pointer-events:none;overflow:hidden}
.lbl{position:absolute;transform:translate(-50%,-50%);white-space:nowrap;font-size:12px;
  color:#cfe3ff;text-shadow:0 0 6px #000,0 0 12px #000;letter-spacing:.5px;
  padding:1px 6px;border-radius:9px;background:rgba(6,12,24,.42);
  border:1px solid rgba(120,170,255,.18);backdrop-filter:blur(2px);
  transition:opacity .18s}
.lbl .d{color:var(--dim);font-size:10px;margin-left:4px}
.lbl.sel{color:#fff;border-color:rgba(255,180,87,.75);background:rgba(40,26,6,.6)}
.lbl.moon{font-size:10.5px;opacity:.9}

/* ---- 顶部标题 ---- */
#topbar{position:fixed;left:16px;top:14px;max-width:min(46vw,620px);pointer-events:none;z-index:5}
#topbar h1{margin:0;font-size:19px;font-weight:600;letter-spacing:2px;
  background:linear-gradient(90deg,#fff,var(--accent) 60%,#7d8bff);
  -webkit-background-clip:text;background-clip:text;color:transparent}
#topbar .sub{font-size:11.5px;color:var(--dim);margin-top:4px;line-height:1.5}
.readouts{display:flex;flex-wrap:wrap;gap:8px;margin-top:9px}
.ro{background:var(--panel);border:1px solid var(--panel-line);border-radius:9px;
  padding:4px 9px;backdrop-filter:blur(8px);font-size:12px;display:flex;gap:7px;align-items:baseline}
.ro .k{color:var(--dim);font-size:10.5px}
.ro b{color:#fff;font-weight:600;font-variant-numeric:tabular-nums}
.ro b.hot{color:var(--accent2)}

/* ---- 右侧控制面板 ---- */
#panel{position:fixed;right:12px;top:12px;bottom:12px;width:330px;z-index:6;
  background:var(--panel);border:1px solid var(--panel-line);border-radius:14px;
  backdrop-filter:blur(14px);padding:10px 12px 16px;overflow-y:auto;
  box-shadow:0 10px 40px rgba(0,0,0,.55);transition:transform .28s ease,opacity .28s}
#panel.hide{transform:translateX(calc(100% + 20px));opacity:0;pointer-events:none}
#panelToggle{position:absolute;right:10px;top:8px;background:transparent;border:1px solid var(--panel-line);
  color:var(--dim);border-radius:8px;width:26px;height:24px;cursor:pointer;font-size:12px;line-height:1}
#panelToggle:hover{color:#fff;border-color:var(--accent)}
#panel section{margin-top:14px;padding-top:12px;border-top:1px solid rgba(120,170,255,.10)}
#panel section:first-of-type{border-top:none;padding-top:2px}
#panel h2{margin:0 0 8px;font-size:12.5px;font-weight:600;color:var(--accent);letter-spacing:1px}
.note{margin:7px 0 0;font-size:11px;line-height:1.65;color:var(--dim)}
.note b{color:#cfe3ff;font-weight:600}
.row{display:flex;align-items:center;justify-content:space-between;gap:8px;margin-top:8px;font-size:12px;color:var(--dim)}
.row.btns{gap:6px}
.row.btns button{flex:1}
.row b{color:#fff}
label.row>span{white-space:nowrap}
input[type=range]{-webkit-appearance:none;appearance:none;height:22px;background:transparent;flex:1;min-width:110px;cursor:pointer}
input[type=range]::-webkit-slider-runnable-track{height:4px;border-radius:3px;
  background:linear-gradient(90deg,rgba(108,198,255,.75),rgba(120,140,255,.30))}
input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:14px;height:14px;border-radius:50%;
  background:#fff;border:2px solid var(--accent);margin-top:-5px;box-shadow:0 0 8px rgba(108,198,255,.8)}
input[type=range]::-moz-range-track{height:4px;border-radius:3px;background:rgba(108,198,255,.5)}
input[type=range]::-moz-range-thumb{width:12px;height:12px;border:2px solid var(--accent);background:#fff;border-radius:50%}
button{font-family:inherit;font-size:11.5px;color:var(--txt);background:rgba(255,255,255,.05);
  border:1px solid var(--panel-line);border-radius:8px;padding:6px 8px;cursor:pointer;transition:.15s}
button:hover{background:rgba(108,198,255,.16);border-color:var(--accent);color:#fff}
button.on{background:rgba(108,198,255,.22);border-color:var(--accent);color:#fff;box-shadow:0 0 10px rgba(108,198,255,.25) inset}
.presets{display:grid;grid-template-columns:repeat(4,1fr);gap:6px}
.presets button{padding:6px 2px}
.presets.goto{grid-template-columns:repeat(4,1fr)}
.seg{display:flex;gap:6px;margin-top:4px}
.seg button{flex:1}
.seg.col{flex-direction:column;gap:5px}
.seg.col button{width:100%;text-align:center;padding:6px 4px}
input[type=range]:disabled{opacity:.4;cursor:not-allowed}
select{background:rgba(8,14,26,.9);color:var(--txt);border:1px solid var(--panel-line);border-radius:8px;
  padding:5px 8px;font-size:11.5px;font-family:inherit;max-width:150px}
.chk{display:flex;align-items:center;gap:8px;font-size:12px;color:var(--txt);padding:4.5px 0;cursor:pointer}
.chk input{appearance:none;-webkit-appearance:none;width:15px;height:15px;border-radius:4px;
  border:1px solid rgba(120,170,255,.45);background:rgba(255,255,255,.04);cursor:pointer;position:relative;flex:none}
.chk input:checked{background:var(--accent);border-color:var(--accent)}
.chk input:checked::after{content:"";position:absolute;left:4.5px;top:1px;width:4px;height:8px;
  border:solid #04101c;border-width:0 2px 2px 0;transform:rotate(42deg)}
.chk:hover{color:#fff}

/* ---- 引力对比条 ---- */
.bars{margin-top:8px}
.bar-item{display:flex;align-items:center;gap:7px;font-size:11px;margin-top:5px}
.bar-item .nm{width:38px;color:#cfe3ff;flex:none}
.bar-item .bar{flex:1;height:8px;background:rgba(255,255,255,.06);border-radius:5px;overflow:hidden}
.bar-item .bar i{display:block;height:100%;border-radius:5px;
  background:linear-gradient(90deg,var(--accent),#7d8bff)}
.bar-item .vl{width:56px;text-align:right;color:var(--dim);font-variant-numeric:tabular-nums;flex:none}

/* ---- 天体资料卡 ---- */
#info{position:fixed;left:16px;bottom:16px;width:330px;max-height:56vh;overflow-y:auto;z-index:6;
  background:var(--panel);border:1px solid var(--panel-line);border-radius:14px;backdrop-filter:blur(14px);
  padding:12px 14px 14px;box-shadow:0 10px 40px rgba(0,0,0,.55);transition:opacity .2s,transform .2s}
#info.hidden{opacity:0;transform:translateY(14px);pointer-events:none}
#info h3{margin:0 0 2px;font-size:16px;color:#fff;letter-spacing:1px}
#info h3 small{color:var(--dim);font-size:11px;margin-left:6px;letter-spacing:0}
#infoClose{position:absolute;right:8px;top:8px;padding:2px 7px;font-size:11px;border-radius:6px}
#info .live{display:grid;grid-template-columns:1fr 1fr;gap:5px;margin:9px 0 10px}
#info .live div{background:rgba(108,198,255,.09);border:1px solid rgba(108,198,255,.16);
  border-radius:8px;padding:5px 7px;font-size:11px;line-height:1.35}
#info .live div span{display:block;color:var(--dim);font-size:10px}
#info .live div b{color:#fff;font-weight:600;font-variant-numeric:tabular-nums}
#info .live div.hl{background:rgba(255,180,87,.12);border-color:rgba(255,180,87,.3)}
#info .live div.hl b{color:var(--accent2)}
#info .kv{font-size:11.5px;line-height:1.6}
#info .kv div{display:flex;gap:8px;padding:3.5px 0;border-bottom:1px dashed rgba(120,170,255,.10)}
#info .kv div:last-child{border-bottom:none}
#info .kv dt{color:var(--dim);width:88px;flex:none}
#info .kv dd{margin:0;color:#e6eeff}
#info .kv dd.lock{color:var(--ok)}
#info .formula{margin-top:8px;padding:7px 9px;border-radius:8px;background:rgba(0,0,0,.35);
  border:1px solid rgba(255,180,87,.22);font-family:ui-monospace,Consolas,monospace;font-size:10.5px;
  color:#ffd9a0;line-height:1.7;word-break:break-all}

/* ---- 底部提示 ---- */
#hint{position:fixed;left:16px;bottom:0;padding:0 0 8px;font-size:11px;color:var(--dim);z-index:4}
#hint .tag{color:var(--accent);border:1px solid rgba(108,198,255,.3);border-radius:6px;padding:1px 6px;font-size:10.5px}
#info:not(.hidden)~#hint{display:none}

/* ---- 加载遮罩 ---- */
#loading{position:fixed;inset:0;background:radial-gradient(circle at 50% 45%,#0a1226,#03050b 70%);
  z-index:50;display:flex;align-items:center;justify-content:center;transition:opacity .5s}
#loading.done{opacity:0;pointer-events:none}
#loading .box{text-align:center;width:min(86vw,420px)}
#loading .t{font-size:15px;color:#fff;letter-spacing:1px}
#loading .bar{height:3px;border-radius:3px;background:rgba(255,255,255,.1);margin:16px 0 8px;overflow:hidden}
#loading .bar i{display:block;height:100%;width:38%;border-radius:3px;
  background:linear-gradient(90deg,transparent,var(--accent),#7d8bff,transparent);
  box-shadow:0 0 12px var(--accent);animation:sweep 1.1s ease-in-out infinite}
@keyframes sweep{0%{transform:translateX(-110%)}100%{transform:translateX(300%)}}
#loading .p{font-size:12px;color:var(--accent);font-variant-numeric:tabular-nums}
#loading .s{font-size:11px;color:var(--dim);margin-top:12px;line-height:1.6}

@media (max-width:900px){
  #panel{width:calc(100vw - 24px);left:12px;right:12px;bottom:12px;top:auto;max-height:52vh}
  #panel.hide{transform:translateY(calc(100% + 20px))}
  #info{width:calc(100vw - 24px);left:12px;bottom:auto;top:64px;max-height:44vh}
  #topbar{max-width:calc(100vw - 30px)}
  #topbar h1{font-size:16px}
  #hint{display:none}
}