/* ═══════════════════════════════════════════════════════════════
   AfriKDP AI — shared design system
   Calm, neutral, product-grade. One accent. Hairline borders.
   Used by copilot.html, book-writer.html, ai-studio.html, study.html
   ═══════════════════════════════════════════════════════════════ */
:root{
  --bg:#f7f7f5; --surface:#ffffff; --surface-2:#f2f2f0; --surface-3:#e9e9e6;
  --border:#e6e5e1; --border-2:#d6d4cd;
  --text:#1a1917; --text-2:#55534d; --text-3:#8a877f; --text-4:#b3b0a8;
  --accent:#b5541e; --accent-2:#9c4717; --accent-soft:#fbf0e8; --accent-ring:rgba(181,84,30,.22);
  --success:#1f8a4c; --success-soft:#e9f5ee; --warn:#b7791f; --warn-soft:#fbf3e2; --danger:#c23b2b; --danger-soft:#fbeae7;
  --ink:#111110; --ink-2:#2b2a27;
  --r-sm:8px; --r:12px; --r-lg:16px; --r-xl:22px;
  --sh-sm:0 1px 2px rgba(20,18,15,.05); --sh:0 4px 14px -6px rgba(20,18,15,.14),0 1px 2px rgba(20,18,15,.05); --sh-lg:0 24px 60px -24px rgba(20,18,15,.28),0 2px 6px rgba(20,18,15,.06);
  --font:"Inter",ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,sans-serif; --serif:"Newsreader","Iowan Old Style",Georgia,serif; --mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,monospace;
  --ease:cubic-bezier(.2,.7,.2,1); --t:160ms;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:var(--font);font-size:14px;line-height:1.5;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer;background:none;border:0;padding:0}
a{color:inherit;text-decoration:none}
::selection{background:var(--accent-soft)}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:6px}
[hidden]{display:none!important}
img[src=""],img:not([src]){visibility:hidden}
::-webkit-scrollbar{width:10px;height:10px}::-webkit-scrollbar-thumb{background:var(--border-2);border-radius:6px;border:3px solid transparent;background-clip:padding-box}::-webkit-scrollbar-track{background:transparent}

/* Icons (inline sprite in each page) */
.i{width:16px;height:16px;flex:none;stroke:currentColor;fill:none;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;vertical-align:-3px}
.i.sm{width:14px;height:14px}.i.lg{width:20px;height:20px}

/* Type */
.h1{font-size:24px;font-weight:600;letter-spacing:-.02em;line-height:1.2;margin:0}
.h2{font-size:18px;font-weight:600;letter-spacing:-.01em;line-height:1.3;margin:0}
.h3{font-size:15px;font-weight:600;margin:0}
.serif{font-family:var(--serif);font-weight:400;letter-spacing:-.01em}
.muted{color:var(--text-2)}.faint{color:var(--text-3)}
.small{font-size:12.5px}.xs{font-size:11.5px}
.eyebrow{font-size:11px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--text-3)}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:7px;height:34px;padding:0 13px;border-radius:var(--r-sm);font-size:13.5px;font-weight:500;border:1px solid var(--border);background:var(--surface);color:var(--text);white-space:nowrap;transition:background var(--t) var(--ease),border-color var(--t),box-shadow var(--t),transform var(--t),opacity var(--t);box-shadow:var(--sh-sm);user-select:none}
.btn:hover{background:var(--surface-2);border-color:var(--border-2)}
.btn:active{transform:translateY(1px)}
.btn.primary{background:var(--ink);border-color:var(--ink);color:#fff;box-shadow:none}.btn.primary:hover{background:var(--ink-2);border-color:var(--ink-2)}
.btn.accent{background:var(--accent);border-color:var(--accent);color:#fff;box-shadow:none}.btn.accent:hover{background:var(--accent-2);border-color:var(--accent-2)}
.btn.ghost{background:transparent;border-color:transparent;box-shadow:none}.btn.ghost:hover{background:var(--surface-2)}
.btn.soft{background:var(--surface-2);border-color:transparent;box-shadow:none}.btn.soft:hover{background:var(--surface-3)}
.btn.danger{color:var(--danger)}.btn.danger:hover{background:var(--danger-soft);border-color:transparent}
.btn.sm{height:28px;padding:0 10px;font-size:12.5px;border-radius:7px}
.btn.lg{height:40px;padding:0 18px;font-size:14px;border-radius:10px}
.btn.block{width:100%}
.btn[disabled],.btn.disabled{opacity:.45;cursor:not-allowed;transform:none}
.locked{opacity:.45;cursor:not-allowed}
.plan-lock{display:inline-flex;margin-left:6px;vertical-align:middle}
a.btn.disabled{pointer-events:auto}
.ibtn{display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;border-radius:var(--r-sm);color:var(--text-2);transition:background var(--t),color var(--t)}
.ibtn:hover{background:var(--surface-2);color:var(--text)}
.ibtn.sm{width:26px;height:26px}
.ibtn.active{background:var(--surface-3);color:var(--text)}

/* Inputs */
.input,.select,.textarea{width:100%;height:36px;padding:0 11px;border:1px solid var(--border);border-radius:var(--r-sm);background:var(--surface);font-size:13.5px;transition:border-color var(--t),box-shadow var(--t)}
.input:hover,.select:hover,.textarea:hover{border-color:var(--border-2)}
.input:focus,.select:focus,.textarea:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-ring)}
.textarea{height:auto;min-height:88px;padding:9px 11px;line-height:1.55;resize:vertical}
.select{appearance:none;background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%238a877f' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'><path d='m6 9 6 6 6-6'/></svg>");background-repeat:no-repeat;background-position:right 10px center;padding-right:30px}
.field{display:flex;flex-direction:column;gap:6px;margin-bottom:14px}
.field>label{font-size:12.5px;font-weight:500;color:var(--text-2)}
.field .hint{font-size:12px;color:var(--text-3)}
.check{display:flex;align-items:center;gap:9px;font-size:13.5px;cursor:pointer;user-select:none}
.check input{width:16px;height:16px;accent-color:var(--ink);margin:0}
.switch{position:relative;width:34px;height:20px;border-radius:999px;background:var(--border-2);transition:background var(--t);flex:none}
.switch::after{content:"";position:absolute;top:2px;left:2px;width:16px;height:16px;border-radius:50%;background:#fff;transition:transform var(--t) var(--ease);box-shadow:var(--sh-sm)}
.switch.on{background:var(--ink)}.switch.on::after{transform:translateX(14px)}
.range{width:100%;accent-color:var(--ink)}
.color{width:100%;height:34px;border:1px solid var(--border);border-radius:var(--r-sm);padding:2px;background:#fff}

/* Surfaces */
.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:18px 20px}
.card.flat{box-shadow:none}
.card+.card{margin-top:12px}
.card .card-h{display:flex;align-items:flex-start;justify-content:space-between;gap:12px;margin-bottom:12px}
.divider{height:1px;background:var(--border);margin:14px 0}
.chip{display:inline-flex;align-items:center;gap:6px;height:24px;padding:0 9px;border-radius:999px;font-size:12px;font-weight:500;background:var(--surface-2);color:var(--text-2);border:1px solid transparent;white-space:nowrap}
.chip.outline{background:transparent;border-color:var(--border)}
.chip.success{background:var(--success-soft);color:var(--success)}.chip.warn{background:var(--warn-soft);color:var(--warn)}.chip.danger{background:var(--danger-soft);color:var(--danger)}.chip.accent{background:var(--accent-soft);color:var(--accent)}
.chip.dot::before{content:"";width:6px;height:6px;border-radius:50%;background:currentColor}
.badge{display:inline-flex;align-items:center;height:18px;padding:0 6px;border-radius:5px;font-size:11px;font-weight:600;background:var(--surface-3);color:var(--text-2)}
.kbd{font-family:var(--mono);font-size:11px;padding:1px 5px;border:1px solid var(--border-2);border-bottom-width:2px;border-radius:5px;background:var(--surface);color:var(--text-2)}
.tabs{display:flex;gap:2px;border-bottom:1px solid var(--border)}
.tabs button{height:38px;padding:0 12px;font-size:13.5px;font-weight:500;color:var(--text-2);border-bottom:2px solid transparent;margin-bottom:-1px;transition:color var(--t),border-color var(--t);white-space:nowrap}
.tabs button:hover{color:var(--text)}
.tabs button.active{color:var(--text);border-bottom-color:var(--ink)}
.seg{display:inline-flex;background:var(--surface-2);border-radius:var(--r-sm);padding:3px;gap:2px}
.seg button{height:28px;padding:0 11px;border-radius:6px;font-size:12.5px;font-weight:500;color:var(--text-2);transition:all var(--t)}
.seg button.active{background:var(--surface);color:var(--text);box-shadow:var(--sh-sm)}
.table{width:100%;border-collapse:collapse;font-size:13px}
.table th{text-align:left;font-size:11.5px;font-weight:600;color:var(--text-3);letter-spacing:.04em;text-transform:uppercase;padding:8px 10px;border-bottom:1px solid var(--border)}
.table td{padding:10px;border-bottom:1px solid var(--border);vertical-align:top}
.table tr:last-child td{border-bottom:0}
.list{margin:0;padding-left:18px;color:var(--text-2)}.list li{margin:3px 0}
.progress{height:6px;border-radius:3px;background:var(--surface-3);overflow:hidden}
.progress i{display:block;height:100%;background:var(--ink);border-radius:3px;transition:width .5s var(--ease)}
.progress.indet i{width:35%;animation:indet 1.4s var(--ease) infinite}
@keyframes indet{0%{transform:translateX(-100%)}100%{transform:translateX(300%)}}
.skeleton{background:linear-gradient(90deg,var(--surface-2) 25%,var(--surface-3) 50%,var(--surface-2) 75%);background-size:200% 100%;animation:sk 1.3s infinite;border-radius:8px}
@keyframes sk{0%{background-position:200% 0}100%{background-position:-200% 0}}
.empty{text-align:center;padding:44px 20px;color:var(--text-2)}
.empty .h3{margin-bottom:4px;color:var(--text)}
.empty .i{width:28px;height:28px;color:var(--text-4);margin-bottom:10px}
.alert{padding:10px 12px;border-radius:var(--r-sm);font-size:13px;line-height:1.5;border:1px solid var(--border);background:var(--surface-2)}
.alert.danger{background:var(--danger-soft);border-color:transparent;color:var(--danger)}
.alert.success{background:var(--success-soft);border-color:transparent;color:var(--success)}
.alert.warn{background:var(--warn-soft);border-color:transparent;color:var(--warn)}
.kv{display:grid;grid-template-columns:130px 1fr;gap:8px 16px;font-size:13.5px}
.kv dt{color:var(--text-3);font-size:12.5px;padding-top:1px}.kv dd{margin:0;color:var(--text)}
.stack{display:flex;flex-direction:column;gap:12px}
.row{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.grid2{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:12px}
.grid3{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px}

/* App shell */
.shell{display:grid;grid-template-columns:260px 1fr;height:100dvh;overflow:hidden}
.shell.rail{grid-template-columns:260px 1fr 300px}
.shell.collapsed{grid-template-columns:0 1fr}
.shell.rail.collapsed{grid-template-columns:0 1fr 300px}
.side{background:var(--surface-2);border-right:1px solid var(--border);display:flex;flex-direction:column;min-width:0;overflow:hidden}
.side-in{width:260px;display:flex;flex-direction:column;height:100%}
.side-top{height:52px;display:flex;align-items:center;justify-content:space-between;padding:0 12px 0 16px}
.brand{display:flex;align-items:center;gap:8px;font-weight:500;font-size:14px;letter-spacing:-.01em}
.brand b{font-weight:700}
.brand img{width:22px;height:22px;border-radius:5px;flex:none}
.brand .mark{width:22px;height:22px;border-radius:6px;background:var(--ink);display:grid;place-items:center;color:#fff}
.brand .mark .i{width:13px;height:13px;stroke-width:2.2}
.side-scroll{flex:1;overflow:auto;padding:4px 8px 12px}
.side-sec{font-size:11px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--text-3);padding:14px 10px 6px}
.nav-item{display:flex;align-items:center;gap:9px;height:34px;padding:0 10px;border-radius:var(--r-sm);font-size:13.5px;color:var(--text-2);cursor:pointer;transition:background var(--t),color var(--t);user-select:none;position:relative}
.nav-item:hover{background:rgba(0,0,0,.045);color:var(--text)}
.nav-item.active{background:var(--surface);color:var(--text);box-shadow:var(--sh-sm);font-weight:500}
.nav-item .i{color:var(--text-3)}.nav-item.active .i{color:var(--text)}
.nav-item .t{flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.nav-item .end{margin-left:auto;font-size:11.5px;color:var(--text-3)}
.nav-item .hover-act{display:none;gap:2px}.nav-item:hover .hover-act{display:inline-flex}.nav-item:hover .end{display:none}
.side-foot{border-top:1px solid var(--border);padding:10px 12px;display:flex;align-items:center;gap:10px;font-size:12.5px;color:var(--text-2)}
.avatar{width:26px;height:26px;border-radius:50%;background:var(--ink);color:#fff;display:grid;place-items:center;font-size:11px;font-weight:600}
.status-dot{width:7px;height:7px;border-radius:50%;background:var(--success);display:inline-block;margin-right:6px}
.status-dot.off{background:var(--text-4)}
.main{display:flex;flex-direction:column;min-width:0;min-height:0;background:var(--bg)}
.topbar{height:52px;display:flex;align-items:center;gap:10px;padding:0 16px;border-bottom:1px solid var(--border);background:var(--surface);flex:none}
.topbar .title{font-weight:600;font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.topbar .crumbs{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--text-3)}
.topbar .crumbs b{color:var(--text);font-weight:500}
.topbar .spacer{flex:1}
.content{flex:1;overflow:auto;min-height:0}
.page-h{display:flex;align-items:flex-start;justify-content:space-between;gap:16px;margin-bottom:18px}
.page-h p{margin:4px 0 0;color:var(--text-2);max-width:640px}
.rail-panel{background:var(--surface);border-left:1px solid var(--border);display:flex;flex-direction:column;min-width:0;overflow:hidden}
.rail-tabs{display:flex;border-bottom:1px solid var(--border);height:44px;flex:none}
.rail-tabs button{flex:1;display:flex;align-items:center;justify-content:center;gap:6px;font-size:12px;font-weight:500;color:var(--text-3);border-bottom:2px solid transparent;margin-bottom:-1px}
.rail-tabs button.active{color:var(--text);border-bottom-color:var(--ink)}
.rail-body{flex:1;overflow:auto;padding:14px}

.scrim{display:none}
/* Menu / modal / toast */
.menu{position:absolute;z-index:60;min-width:200px;background:var(--surface);border:1px solid var(--border);border-radius:var(--r);box-shadow:var(--sh-lg);padding:5px;animation:pop var(--t) var(--ease)}
.menu button,.menu a{display:flex;align-items:center;gap:9px;width:100%;height:32px;padding:0 9px;border-radius:7px;font-size:13px;color:var(--text);text-align:left}
.menu button:hover,.menu a:hover{background:var(--surface-2)}
.menu .sep{height:1px;background:var(--border);margin:4px 0}
.menu .lbl{font-size:11px;color:var(--text-3);padding:6px 9px 2px;font-weight:600;letter-spacing:.05em;text-transform:uppercase}
.modal{position:fixed;inset:0;z-index:100;display:none;align-items:center;justify-content:center;padding:20px;background:rgba(17,17,16,.42);backdrop-filter:blur(2px)}
.modal.open{display:flex}
.modal-box{background:var(--surface);border-radius:var(--r-lg);width:100%;max-width:640px;max-height:92vh;overflow:auto;box-shadow:var(--sh-lg);animation:pop 220ms var(--ease)}
.modal-h{display:flex;align-items:center;justify-content:space-between;padding:16px 20px;border-bottom:1px solid var(--border)}
.modal-b{padding:20px}
.modal-f{display:flex;justify-content:flex-end;gap:8px;padding:14px 20px;border-top:1px solid var(--border)}
.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%) translateY(8px);background:var(--ink);color:#fff;font-size:13px;padding:10px 14px;border-radius:10px;z-index:300;opacity:0;pointer-events:none;transition:opacity var(--t),transform var(--t) var(--ease);box-shadow:var(--sh-lg);display:flex;align-items:center;gap:8px;max-width:calc(100vw - 32px)}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0);pointer-events:auto}
.tip{position:relative}
@keyframes pop{from{opacity:0;transform:translateY(4px) scale(.98)}to{opacity:1;transform:none}}
@keyframes fade{from{opacity:0}to{opacity:1}}
@keyframes rise{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
.rise{animation:rise 240ms var(--ease) both}
.fade{animation:fade 200ms var(--ease) both}
.spinner{width:16px;height:16px;border-radius:50%;border:2px solid var(--border-2);border-top-color:var(--text);animation:spin .7s linear infinite;flex:none}
.spinner.light{border-color:rgba(255,255,255,.3);border-top-color:#fff}
@keyframes spin{to{transform:rotate(360deg)}}
.dots{display:inline-flex;gap:4px;align-items:center;height:16px}
.dots i{width:5px;height:5px;border-radius:50%;background:var(--text-3);animation:dot 1.2s infinite}
.dots i:nth-child(2){animation-delay:.15s}.dots i:nth-child(3){animation-delay:.3s}
@keyframes dot{0%,80%,100%{opacity:.3;transform:translateY(0)}40%{opacity:1;transform:translateY(-2px)}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation-duration:.01ms!important;transition-duration:.01ms!important}}
@media (max-width:900px){
  .shell,.shell.rail,.shell.collapsed{grid-template-columns:1fr}
  .side{position:fixed;left:0;top:0;bottom:0;width:260px;z-index:70;transform:translateX(-100%);transition:transform 240ms var(--ease);box-shadow:var(--sh-lg)}
  .shell.side-open .side{transform:none}
  .rail-panel{position:fixed;right:0;top:0;bottom:0;width:min(320px,92vw);z-index:70;transform:translateX(100%);transition:transform 240ms var(--ease);box-shadow:var(--sh-lg)}
  .shell.rail-open .rail-panel{transform:none}
  .scrim{position:fixed;inset:0;background:rgba(17,17,16,.35);z-index:65;display:none}
  .shell.side-open .scrim,.shell.rail-open .scrim{display:block}
}