:root {
  --bg:        #0d1117;
  --surface:   #161b22;
  --surface-2: #1c232c;
  --line:      #263242;
  --line-soft: #1e2733;
  --fg:        #e6edf3;
  --fg-dim:    #9aa8b8;
  --fg-faint:  #6b7a8d;
  --accent:    #4c8dff;
  --accent-fg: #ffffff;
  --done:      #2ea86b;
  --danger:    #e5534b;
  --radius:    10px;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
}

[data-theme="light"] {
  --bg:        #f6f8fa;
  --surface:   #ffffff;
  --surface-2: #f0f3f6;
  --line:      #d8dee4;
  --line-soft: #e6eaef;
  --fg:        #1f2328;
  --fg-dim:    #57606a;
  --fg-faint:  #848d97;
  --accent:    #0969da;
  --done:      #1a7f4b;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.app { max-width: 620px; margin: 0 auto; padding: 40px 20px 60px; }

/* header */

.head { display: flex; align-items: flex-start; gap: 14px; margin-bottom: 22px; }
.title { flex: 1; min-width: 0; }
.head h1 { margin: 0; font-size: 27px; letter-spacing: -0.02em; }
.sub { margin: 2px 0 0; font-size: 13px; color: var(--fg-faint); }
.head-actions { display: flex; gap: 8px; align-items: center; }

.ghost, .icon {
  background: transparent; border: 1px solid var(--line);
  color: var(--fg-dim); border-radius: 8px;
  font: inherit; font-size: 13px; padding: 6px 12px; cursor: pointer;
}
.icon { padding: 6px 10px; }
.ghost.sm { padding: 4px 10px; font-size: 12.5px; }
.ghost:hover, .icon:hover { color: var(--fg); border-color: var(--fg-faint); }

/* composer */

.composer { display: flex; gap: 9px; margin-bottom: 16px; }

#input {
  flex: 1; min-width: 0;
  padding: 12px 14px;
  background: var(--surface); color: var(--fg);
  border: 1px solid var(--line); border-radius: var(--radius);
  font: inherit; font-size: 15px;
}
#input::placeholder { color: var(--fg-faint); }
#input:focus { outline: 2px solid var(--accent); outline-offset: -1px; border-color: var(--accent); }

.add {
  flex: none; padding: 0 20px;
  background: var(--accent); color: var(--accent-fg);
  border: 0; border-radius: var(--radius);
  font: inherit; font-size: 14.5px; font-weight: 550; cursor: pointer;
}
.add:hover { filter: brightness(1.08); }
.add:disabled { background: var(--line); color: var(--fg-faint); cursor: not-allowed; }

/* filter bar */

.bar { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.filters { display: flex; gap: 5px; }

.chip {
  background: transparent; border: 1px solid var(--line);
  color: var(--fg-dim); border-radius: 999px;
  padding: 4px 13px; font: inherit; font-size: 12.5px; cursor: pointer;
}
.chip:hover { color: var(--fg); }
.chip.on { background: var(--accent); border-color: var(--accent); color: var(--accent-fg); }

.count { margin-left: auto; font-size: 12.5px; color: var(--fg-faint); }

/* list */

.list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 7px; }

.item {
  display: flex; align-items: flex-start; gap: 11px;
  padding: 12px 13px;
  background: var(--surface);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
}
.item.done { background: var(--surface-2); }

.check {
  flex: none; width: 20px; height: 20px; margin-top: 1px;
  border: 1.5px solid var(--fg-faint); border-radius: 6px;
  background: transparent; cursor: pointer;
  display: grid; place-items: center;
  font-size: 12px; color: transparent; padding: 0;
}
.check:hover { border-color: var(--accent); }
.item.done .check { background: var(--done); border-color: var(--done); color: #fff; }

.text {
  flex: 1; min-width: 0;
  overflow-wrap: anywhere;
  cursor: text;
  border: 0; background: transparent; color: inherit;
  font: inherit; padding: 0;
}
.item.done .text { color: var(--fg-faint); text-decoration: line-through; }

.edit {
  flex: 1; min-width: 0;
  background: var(--bg); color: var(--fg);
  border: 1px solid var(--accent); border-radius: 6px;
  font: inherit; padding: 2px 7px;
}
.edit:focus { outline: none; }

.del {
  flex: none; background: transparent; border: 0;
  color: var(--fg-faint); cursor: pointer;
  font-size: 17px; line-height: 1; padding: 0 3px;
}
.del:hover { color: var(--danger); }

/* states */

.empty { text-align: center; color: var(--fg-faint); font-size: 14px; padding: 34px 0; margin: 0; }

.banner {
  margin-top: 16px; padding: 11px 13px;
  border-radius: var(--radius); font-size: 13.5px;
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  border: 1px solid color-mix(in srgb, var(--accent) 40%, transparent);
}
.banner.bad {
  background: color-mix(in srgb, var(--danger) 12%, transparent);
  border-color: color-mix(in srgb, var(--danger) 45%, transparent);
}
.banner button {
  background: none; border: 0; color: var(--accent);
  font: inherit; text-decoration: underline; cursor: pointer; padding: 0;
}

.foot {
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  margin-top: 34px; padding-top: 16px;
  border-top: 1px solid var(--line-soft);
  font-size: 12px; color: var(--fg-faint);
}
.foot a { color: var(--fg-dim); }

@media (max-width: 480px) {
  .app { padding: 26px 15px 40px; }
  .head h1 { font-size: 23px; }
}