*{box-sizing:border-box;margin:0;padding:0}:root{--bg: #04090d;--panel: #0a141b;--line: #123242;--accent: #35d0ba;--accent-dim: #128a7a;--text: #c8dce2;--muted: #6e8a94;--warn: #ffb547;--hit: #ff5a4d}html,body{height:100%}body{background:radial-gradient(1200px 600px at 50% -10%,rgba(53,208,186,.08),transparent),var(--bg);color:var(--text);font-family:Segoe UI,PingFang SC,Microsoft YaHei,system-ui,sans-serif;font-size:16px}#app{min-height:100%;display:flex;flex-direction:column}#topbar{display:flex;align-items:center;justify-content:space-between;padding:10px 16px;border-bottom:1px solid var(--line);background:#0a141bd9}.brand{font-size:18px;font-weight:700;letter-spacing:1px}.brand .sub{color:var(--accent);font-size:16px;letter-spacing:2px;margin-left:6px}#room-info{display:flex;align-items:center;gap:8px;font-size:16px}#room-code{color:var(--accent);letter-spacing:2px;font-size:18px}button{min-height:46px;padding:10px 18px;border:1px solid var(--line);border-radius:8px;background:#0e1d26;color:var(--text);font-size:16px;cursor:pointer;transition:background .15s,border-color .15s}button:hover{border-color:var(--accent-dim)}button:disabled{opacity:.45;cursor:not-allowed}button.primary{background:var(--accent-dim);border-color:var(--accent);color:#02100d;font-weight:700}main{flex:1;display:flex;align-items:stretch;justify-content:center}.panel{margin:auto;width:min(420px,92vw);background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:28px 24px;display:flex;flex-direction:column;gap:14px}.panel h1{font-size:26px;letter-spacing:2px}.panel .desc{color:var(--muted);font-size:16px}.field{display:flex;flex-direction:column;gap:6px;font-size:16px;color:var(--muted)}input{min-height:46px;padding:10px 12px;border:1px solid var(--line);border-radius:8px;background:#071018;color:var(--text);font-size:16px}.join-row{display:flex;gap:8px}.join-row input{flex:1;min-width:0;text-transform:uppercase;letter-spacing:2px}.join-row button{min-width:88px}.mode-grid{display:grid;grid-template-columns:1fr;gap:10px;width:100%}.mode-card{display:flex;flex-direction:column;align-items:flex-start;gap:4px;width:100%;min-height:88px;padding:14px 16px;text-align:left}.mode-card .mode-name{font-size:18px;font-weight:700}.mode-card .mode-hint{font-size:16px;color:var(--muted);font-weight:400;line-height:1.4}.mode-card.primary .mode-hint{color:#02100d}@media(min-width:720px){.mode-grid{grid-template-columns:repeat(3,1fr)}.panel{width:min(780px,92vw)}}.hint{color:var(--muted);font-size:16px;line-height:1.5}#game{width:100%;max-width:1100px;margin:0 auto;padding:12px 14px 28px;display:flex;flex-direction:column;gap:10px}#status-bar{text-align:center;min-height:30px;font-size:17px;color:var(--accent)}#seat-line{display:flex;justify-content:center;align-items:center;gap:14px;font-size:16px}#seat-line .vs{color:var(--warn);letter-spacing:2px}#seat-me em,#seat-opp em{font-style:normal;color:var(--accent)}#boards{display:flex;gap:18px;justify-content:center;flex-wrap:wrap}.board-pane{display:flex;flex-direction:column;gap:6px;align-items:center}.board-pane h2{font-size:16px;color:var(--muted);letter-spacing:1px;font-weight:600}.board-pane canvas{width:min(46vh,100%);max-width:480px;border:1px solid var(--line);border-radius:10px;touch-action:manipulation}#place-tools{display:flex;flex-direction:column;gap:10px;align-items:center}#ship-row{display:flex;gap:10px;flex-wrap:wrap;justify-content:center}.ship-chip{display:flex;align-items:center;gap:8px;min-height:44px;padding:8px 14px;border:1px solid var(--line);border-radius:8px;cursor:pointer;user-select:none;font-size:16px}.ship-chip.selected{border-color:var(--accent);background:#35d0ba1f}.ship-chip .dots{display:flex;gap:3px}.ship-chip .dots i{width:12px;height:12px;border-radius:3px;background:#2b4a58;display:inline-block}.ship-chip.placed .dots i{background:var(--accent)}#place-actions{display:flex;gap:10px;flex-wrap:wrap;justify-content:center}#battle-actions{display:flex;justify-content:center}.hidden{display:none!important}#toast{position:fixed;left:50%;bottom:26px;transform:translate(-50%);background:#0e1d26;border:1px solid var(--accent-dim);color:var(--text);padding:12px 20px;border-radius:10px;font-size:16px;max-width:88vw;z-index:50}@media(max-width:860px){#boards{flex-direction:column;align-items:center}.board-pane canvas{width:min(88vw,480px)}button{min-height:44px}}