:root{
  --bg:#f4f5f7;
  --appbar:#ffffff;
  --panel:#ebecf0;
  --card:#ffffff;
  --text:#172b4d;
  --dim:#5e6c84;
  --muted:#8993a4;
  --line:#dfe1e6;
  --line2:#c1c7d0;
  --accent:#0d9488;
  --accent2:#0f766e;
  --critical:#dc2626;
  --warning:#d97706;
  --info:#2563eb;
  --done:#16a34a;
  --shadow:0 1px 2px rgba(9,30,66,.16),0 0 1px rgba(9,30,66,.12);
}
*{box-sizing:border-box;}
html,body{height:100%;}
body{
  margin:0;background:var(--bg);color:var(--text);
  font-family:system-ui,-apple-system,"Segoe UI","Hiragino Kaku Gothic ProN",Meiryo,sans-serif;
  -webkit-font-smoothing:antialiased;
  overflow:hidden;
}
button{font-family:inherit;}

/* App bar */
.appbar{
  height:54px;display:flex;align-items:center;gap:12px;padding:0 16px;
  background:var(--appbar);border-bottom:1px solid var(--line);
}
.appbar .brand{font-weight:800;font-size:16px;display:flex;align-items:center;gap:8px;}
.appbar .brand .logo{width:24px;height:24px;border-radius:7px;background:linear-gradient(135deg,var(--accent),#22c55e);
  display:inline-flex;align-items:center;justify-content:center;font-size:14px;color:#fff;}
.appbar .spacer{flex:1;}
.appbar .email{color:var(--muted);font-size:12px;max-width:200px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;}
.appbar .badges{display:flex;gap:6px;}
.badge{font-size:12px;font-weight:700;padding:4px 10px;border-radius:999px;color:#fff;display:inline-flex;gap:4px;align-items:center;}
.badge.unread{background:var(--accent);}
.badge.critical{background:var(--critical);}
.iconbtn{background:#fff;color:var(--dim);border:1px solid var(--line2);border-radius:8px;padding:7px 12px;font-size:13px;font-weight:600;cursor:pointer;white-space:nowrap;display:inline-flex;align-items:center;text-decoration:none;}
.iconbtn:hover{background:#f4f5f7;color:var(--text);}

/* Filters */
.filters{
  display:flex;align-items:center;gap:14px;padding:10px 16px;
  background:var(--appbar);border-bottom:1px solid var(--line);overflow-x:auto;
}
.tabs{display:flex;gap:6px;}
.tab{background:#fff;color:var(--dim);border:1px solid var(--line2);border-radius:999px;padding:6px 14px;font-size:13px;font-weight:600;cursor:pointer;display:inline-flex;gap:6px;align-items:center;}
.tab.on{background:var(--accent);border-color:var(--accent);color:#fff;}
.tab .n{font-size:11px;background:rgba(0,0,0,.08);padding:1px 6px;border-radius:999px;}
.tab.on .n{background:rgba(255,255,255,.25);}
.dropdowns{display:flex;gap:6px;margin-left:auto;}
.dropdowns select{background:#fff;color:var(--text);border:1px solid var(--line2);border-radius:8px;padding:6px 8px;font-size:13px;cursor:pointer;}

/* Layout */
.layout{
  display:grid;grid-template-columns:380px 1fr;
  height:calc(100vh - 54px - 51px);
}
.list{
  border-right:1px solid var(--line);overflow-y:auto;background:#fff;
}
.detail{padding:24px;overflow-y:auto;}
.detail-empty{color:var(--muted);text-align:center;padding:40px;}

/* Row */
.row{padding:12px 16px;border-bottom:1px solid var(--line);cursor:pointer;border-left:4px solid transparent;}
.row:hover{background:#fafbfc;}
.row.sel{background:#e6fffa;border-left-color:var(--accent);}
.row.sev-critical{border-left-color:var(--critical);}
.row.sev-warning{border-left-color:var(--warning);}
.row.sev-info{border-left-color:var(--info);}
.row.sel.sev-critical{background:#fef2f2;}
.row.unread .row-head .title{font-weight:700;}
.row.read .row-head .title,.row.done .row-head .title{color:var(--dim);}
.row.done{opacity:.65;}
.row-head{display:flex;gap:8px;align-items:flex-start;margin-bottom:4px;}
.row-head .sev{font-size:14px;}
.row-head .title{font-size:14px;flex:1;}
.row-meta{font-size:11px;color:var(--muted);display:flex;gap:8px;flex-wrap:wrap;align-items:center;}
.row-meta .src{font-weight:600;color:var(--dim);}
.row-meta .time{margin-left:auto;}
.st{font-size:10px;padding:1px 6px;border-radius:4px;font-weight:700;}
.st.unread{background:#e6fffa;color:var(--accent2);}
.st.read{background:#f1f5f9;color:var(--dim);}
.st.done{background:#dcfce7;color:#166534;}
.st.snoozed{background:#fef3c7;color:#92400e;}

/* Detail */
.msg-head h2{margin:0 0 8px 0;font-size:20px;line-height:1.4;}
.msg-meta{font-size:12px;color:var(--muted);margin-bottom:16px;}
.snooze-info{background:#fef3c7;color:#92400e;padding:8px 12px;border-radius:6px;margin-bottom:12px;font-size:13px;}
.extlink{display:inline-block;background:#fff;border:1px solid var(--line2);padding:6px 12px;border-radius:6px;color:var(--text);text-decoration:none;font-size:13px;margin-bottom:16px;}
.extlink:hover{background:#f4f5f7;}
.msg-body{background:#fff;padding:20px;border:1px solid var(--line);border-radius:8px;line-height:1.7;font-size:14px;}
.msg-body h1,.msg-body h2,.msg-body h3{margin-top:1em;}
.msg-body pre{background:#f4f5f7;padding:8px;border-radius:6px;overflow-x:auto;font-size:12px;}
.msg-body code{background:#f4f5f7;padding:1px 6px;border-radius:4px;font-family:Menlo,Consolas,monospace;font-size:12px;}
.msg-body ul{padding-left:1.4em;}
.msg-body a{color:var(--accent);}
.metadata{margin-top:16px;background:#fafbfc;border:1px solid var(--line);padding:12px;border-radius:6px;font-size:11px;color:var(--dim);white-space:pre-wrap;overflow-x:auto;}
.msg-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:20px;}
.msg-actions button{background:#fff;border:1px solid var(--line2);padding:8px 14px;border-radius:6px;cursor:pointer;font-size:13px;font-weight:600;color:var(--text);}
.msg-actions button:hover{background:#f4f5f7;}
.msg-actions button.primary{background:var(--accent);color:#fff;border-color:var(--accent);}
.msg-actions button.primary:hover{background:var(--accent2);}
.msg-actions button.danger{background:#fee;color:var(--critical);border-color:#fecaca;margin-left:auto;}
.msg-actions button.danger:hover{background:#fecaca;}

.empty{padding:30px;text-align:center;color:var(--muted);font-size:13px;}

/* Overlay (mobile detail) */
.overlay{position:fixed;inset:0;background:rgba(9,30,66,.5);z-index:100;display:flex;align-items:flex-end;justify-content:center;}
.overlay[hidden]{display:none;}   /* [hidden]はdisplay:flex指定に負けるため明示 */
.overlay .modal{background:#fff;width:100%;max-width:720px;max-height:92vh;overflow-y:auto;padding:24px;border-radius:16px 16px 0 0;position:relative;}
.overlay .x{position:absolute;top:12px;right:12px;background:none;border:none;font-size:22px;cursor:pointer;color:var(--dim);z-index:1;}

/* Login */
.login-body{display:flex;align-items:center;justify-content:center;overflow:auto;}
.login-wrap{max-width:480px;padding:40px 20px;text-align:center;}
.login-wrap h1{font-size:32px;margin-bottom:8px;}
.login-wrap .sub{color:var(--muted);margin-bottom:24px;}
.bigbtn{display:inline-block;background:var(--accent);color:#fff;padding:12px 24px;border-radius:8px;text-decoration:none;font-weight:700;margin-top:20px;}
.bigbtn:hover{background:var(--accent2);}

/* Mobile */
@media (max-width:720px){
  .layout{grid-template-columns:1fr;}
  .detail{display:none;}
  .appbar .email{display:none;}
  .filters{padding:8px 12px;}
  .tabs{gap:4px;}
  .tab{padding:5px 10px;font-size:12px;}
  .dropdowns{display:none;}
}