:root{
    /* Single-hue theme: set --theme-hue to change the whole site's accent hue */
    --theme-hue: 212; /* default: blue */
    --bg-start: #0f172a;
    --bg-end: #1e293b;
    --card: rgba(30, 41, 59, 0.5);
    --card-hover: rgba(51, 65, 85, 0.6);
    /* derive accents from single hue for a consistent one-color gradient */
    --accent: hsl(var(--theme-hue) 85% 52%);
    --accent-bright: hsl(var(--theme-hue) 85% 62%);
    --accent-2: hsl(var(--theme-hue) 85% 72%);
    --text: #f1f5f9;
    --text-muted: #94a3b8;
    --border: rgba(148, 163, 184, 0.1);
}
*{box-sizing:border-box;margin:0;padding:0}
body{
    font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,'Noto Sans',sans-serif,'Apple Color Emoji','Segoe UI Emoji';
    background:linear-gradient(135deg,var(--bg-start) 0%,var(--bg-end) 100%);
    color:var(--text);
    min-height:100vh;
    display:flex;
    flex-direction:column;
    position:relative;
    overflow-x:hidden;
}
body::before{
    content:'';
    position:fixed;
    top:0;
    left:0;
    width:100%;
    height:100%;
    /* use theme hue for subtle decorative glows so themes affect the background accents */
    background:radial-gradient(circle at 20% 50%, hsla(var(--theme-hue),85%,52%,0.08) 0%, transparent 50%),
               radial-gradient(circle at 80% 80%, hsla(var(--theme-hue),85%,62%,0.06) 0%, transparent 50%);
    pointer-events:none;
    z-index:0;
}
main{max-width:900px;margin:0 auto;padding:80px 24px 40px;position:relative;z-index:1}
header{text-align:center;margin-bottom:60px}
header{position:relative}

/* Top-right action buttons (ログイン / 設定)
    Place them inside page header (header is positioned relative), so they sit at
    the top-right of the header area and behave consistently across pages. */
.top-actions{position:absolute;right:24px;top:16px;display:flex;gap:8px;align-items:center;z-index:50}
.top-actions .button{padding:8px 12px;font-size:0.9rem;box-shadow:0 6px 18px rgba(9,30,66,0.08);border:1px solid rgba(255,255,255,0.06);background:var(--card);color:var(--text);border:1px solid rgba(255,255,255,0.06)}
.top-actions .button:focus{outline:2px solid hsla(var(--theme-hue),85%,52%,0.18)!important}
h1{
    font-size:3.5rem;
    font-weight:800;
    background:linear-gradient(135deg,var(--accent-bright),var(--accent));
    -webkit-background-clip:text;
    background-clip:text;
    -webkit-text-fill-color:transparent;
    margin-bottom:12px;
    letter-spacing:-0.03em;
}
.subtitle{
    color:var(--text-muted);
    font-size:1.1rem;
    font-weight:400;
    letter-spacing:0.02em;
}
.lead{
    text-align:center;
    color:var(--text-muted);
    font-size:1.05rem;
    line-height:1.7;
    margin:40px auto;
    max-width:600px;
}
.about{
    background:var(--card);
    -webkit-backdrop-filter:blur(10px);
    backdrop-filter:blur(10px);
    border:1px solid var(--border);
    border-radius:16px;
    padding:32px;
    margin:0 auto 40px;
    max-width:700px;
}
/* Floating white card used on history and other pages for consistent look */
.floating-card, .heatmap-card {
    background: #ffffff;
    color: #111827;
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    border: 1px solid rgba(0,0,0,0.06);
    box-sizing: border-box;
}
.heatmap-card {
    width: 100%;
    max-width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0 auto;
}

#syncStatus{ margin-left:12px; font-family: monospace; color: var(--text-muted); }
.about h2{
    font-size:1.5rem;
    margin-bottom:16px;
    background:linear-gradient(135deg,var(--accent-bright),var(--accent));
    -webkit-background-clip:text;
    background-clip:text;
    -webkit-text-fill-color:transparent;
}
.about h3{
    font-size:1.1rem;
    margin:24px 0 12px;
    color:var(--text);
}
.about p{
    color:var(--text-muted);
    line-height:1.7;
}
.tech-stack{
    margin-top:20px;
}
.projects{display:grid;gap:24px;margin-top:48px}
.project{
    background:var(--card);
    -webkit-backdrop-filter:blur(10px);
    backdrop-filter:blur(10px);
    border:1px solid var(--border);
    border-radius:16px;
    padding:32px;
    transition:all 0.3s cubic-bezier(0.4,0,0.2,1);
    position:relative;
    overflow:hidden;
}
.project::before{
    content:'';
    position:absolute;
    top:0;
    left:0;
    width:100%;
    height:2px;
    background:linear-gradient(90deg,var(--accent),var(--accent-bright));
    opacity:0;
    transition:opacity 0.3s;
}
.project:hover{
    background:var(--card-hover);
    border-color:rgba(148,163,184,0.2);
    transform:translateY(-4px);
}
.project:hover::before{opacity:1}
.project h2{
    font-size:1.75rem;
    font-weight:700;
    margin-bottom:12px;
    color:var(--text);
}
.project p{
    color:var(--text-muted);
    line-height:1.7;
    margin-bottom:20px;
}
.project .tags{
    display:flex;
    gap:8px;
    flex-wrap:wrap;
    margin-bottom:20px;
}
.tag{
    background:hsla(var(--theme-hue),85%,52%,0.15);
    color:var(--accent-bright);
    padding:4px 12px;
    border-radius:6px;
    font-size:0.85rem;
    font-weight:500;
}
a.button{
    display:inline-flex;
    align-items:center;
    gap:8px;
    padding:12px 24px;
    border-radius:10px;
    background:linear-gradient(135deg,var(--accent),var(--accent-bright));
    color:white;
    text-decoration:none;
    font-weight:600;
    font-size:0.95rem;
    transition:all 0.3s;
    box-shadow:0 4px 12px hsla(var(--theme-hue),85%,52%,0.3);
}
a.button:hover{
    transform:translateY(-2px);
    box-shadow:0 8px 24px hsla(var(--theme-hue),85%,52%,0.4);
}
a.button::after{
    content:'→';
    transition:transform 0.3s;
}
a.button:hover::after{
    transform:translateX(4px);
}
.coming-soon{opacity:0.7}
.coming-soon h2{color:var(--text-muted)}
.coming-soon ul{
    list-style:none;
    padding:0;
}
.coming-soon li{
    padding:8px 0;
    color:var(--text-muted);
    display:flex;
    align-items:center;
    gap:12px;
}
.coming-soon li::before{
    content:'⏱';
    font-size:1.2rem;
}
footer{
    margin-top:auto;
    padding:40px 24px;
    text-align:center;
    color:var(--text-muted);
    font-size:0.9rem;
    position:relative;
    z-index:1;
}
footer a{
    color:var(--accent-bright);
    text-decoration:none;
    transition:color 0.2s;
}
footer a:hover{
    color:var(--accent);
}
@media (max-width:768px){
    h1{font-size:2.5rem}
    main{padding:60px 20px 32px}
    .project{padding:24px}
    .lead{font-size:1rem}
    /* On small screens, move top-actions into normal flow */
    .top-actions{position:static;margin-top:12px;justify-content:center}
}

/* Login modal (トップページ専用) */
.modal-overlay{position:fixed;inset:0;background:rgba(255,255,255,0.6);display:none;align-items:center;justify-content:center;-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);z-index:1000}
.modal-overlay[aria-hidden="false"]{display:flex}
.modal{background:linear-gradient(180deg,rgba(255,255,255,0.03),rgba(255,255,255,0.02));-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);border:1px solid rgba(148,163,184,0.08);padding:20px;border-radius:12px;min-width:320px;max-width:420px}
.modal h3{margin:0 0 8px 0;color:var(--text)}
.modal .modal-body{display:flex;flex-direction:column;gap:8px}
.modal .modal-body label{display:flex;flex-direction:column;font-size:0.9rem;color:var(--text-muted)}
.modal .modal-body input{padding:8px;border-radius:8px;border:1px solid var(--border);margin-top:6px;background:transparent;color:var(--text)}
.modal .modal-actions{display:flex;gap:8px;justify-content:flex-end;margin-top:6px}
.modal .modal-actions .button{padding:8px 12px;border-radius:8px}
.top-btn-register{background:transparent;color:var(--accent-bright)}
.top-btn-close{background:transparent;color:var(--text-muted)}
.top-login-status{color:var(--text-muted);margin-top:8px}
/* header helper */
.header-login-wrap{margin-top:12px}