:root {
  --bg: #080b09;
  --surface: #0f1511;
  --surface-2: #141c17;
  --line: #28352d;
  --text: #eff7f1;
  --muted: #91a197;
  --accent: #65e890;
  --accent-rgb: 101, 232, 144;
  --danger: #ff8989;
  --radius: 16px;
  --mono: "Cascadia Code", "SFMono-Regular", Consolas, monospace;
}

html[data-theme="blue"] { --accent: #6dbbff; --accent-rgb: 109, 187, 255; }
html[data-theme="amber"] { --accent: #f5bd61; --accent-rgb: 245, 189, 97; }

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  color: var(--text);
  background:
    linear-gradient(rgba(var(--accent-rgb), .025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(var(--accent-rgb), .025) 1px, transparent 1px),
    radial-gradient(circle at 50% -20%, rgba(var(--accent-rgb), .1), transparent 35rem),
    var(--bg);
  background-size: 40px 40px, 40px 40px, auto, auto;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

button, input { font: inherit; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; top: -5rem; left: 1rem; z-index: 20; padding: .65rem 1rem; color: #07100a; background: var(--accent); border-radius: 8px; }
.skip-link:focus { top: 1rem; }

.app-shell { width: min(1120px, calc(100% - 2rem)); margin-inline: auto; }
.app-header, .app-footer { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 1rem; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: .7rem; color: var(--text); text-decoration: none; font-weight: 800; letter-spacing: -.02em; }
.brand-prompt { color: var(--accent); font: 800 .9rem var(--mono); }
.system-status { display: flex; align-items: center; gap: .45rem; color: var(--muted); font: .7rem var(--mono); text-transform: uppercase; letter-spacing: .08em; }
.system-status > span { width: 7px; height: 7px; background: var(--accent); border-radius: 50%; box-shadow: 0 0 12px var(--accent); }

main { min-height: calc(100vh - 152px); padding-block: clamp(2.5rem, 7vw, 5.5rem); }
.hero-row, .detail-heading { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(310px, .75fr); gap: clamp(2rem, 7vw, 5rem); align-items: end; margin-bottom: 2.5rem; }
.eyebrow { margin: 0 0 .6rem; color: var(--accent); font: 700 .7rem var(--mono); text-transform: uppercase; letter-spacing: .16em; }
h1, h2, h3 { margin-top: 0; line-height: 1.1; }
h1 { margin-bottom: 1rem; font-size: clamp(2.6rem, 6vw, 5.2rem); letter-spacing: -.055em; }
h2 { margin-bottom: 0; font-size: clamp(1.6rem, 3vw, 2.4rem); letter-spacing: -.035em; }
.intro, .detail-heading > div > p:last-child { max-width: 650px; margin: 0; color: var(--muted); }

.summary-card { display: grid; grid-template-columns: repeat(3, 1fr); padding: .75rem; background: rgba(15, 21, 17, .9); border: 1px solid var(--line); border-radius: var(--radius); }
.summary-card > div { padding: .75rem .35rem; text-align: center; border-right: 1px solid var(--line); }
.summary-card > div:last-child { border-right: 0; }
.summary-card strong, .summary-card span { display: block; }
.summary-card strong { color: var(--accent); font: 800 1.55rem var(--mono); }
.summary-card span { color: var(--muted); font-size: .72rem; }

.task-form { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: .75rem; align-items: end; padding: 1rem; background: rgba(15, 21, 17, .9); border: 1px solid var(--line); border-radius: var(--radius); }
.input-group label { display: block; margin-bottom: .45rem; color: var(--muted); font: .72rem var(--mono); text-transform: uppercase; }
.input-row { display: flex; align-items: center; min-height: 50px; overflow: hidden; background: #080b09; border: 1px solid var(--line); border-radius: 10px; }
.input-row:focus-within { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(var(--accent-rgb), .11); }
.input-row span { padding-left: .9rem; color: var(--accent); font: 800 .9rem var(--mono); }
.input-row input { width: 100%; min-width: 0; min-height: 48px; padding: .75rem .9rem; color: var(--text); background: transparent; border: 0; outline: 0; }
.button { min-height: 50px; padding: .72rem 1.15rem; border: 1px solid transparent; border-radius: 10px; cursor: pointer; font-weight: 800; }
.button-primary { color: #07100a; background: var(--accent); }
.button-primary:hover { filter: brightness(1.08); }
.button:focus-visible, .filter-button:focus-visible, .text-button:focus-visible, .action-button:focus-visible, .task-name:focus-visible, .theme-button:focus-visible, .date-button:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
.validation-message { min-height: 1.4rem; margin: .5rem 0 0; color: var(--danger); font: .76rem var(--mono); }

.toolbar { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin: 1.2rem 0 2.5rem; }
.filters { display: flex; gap: .35rem; padding: .25rem; background: var(--surface); border: 1px solid var(--line); border-radius: 10px; }
.filter-button { min-height: 36px; padding: .45rem .75rem; color: var(--muted); background: transparent; border: 0; border-radius: 7px; cursor: pointer; font-size: .78rem; font-weight: 700; }
.filter-button.active { color: var(--text); background: var(--surface-2); }
.text-button { padding: .25rem; color: var(--accent); background: none; border: 0; cursor: pointer; text-decoration: underline; text-underline-offset: 3px; }
.danger-text { color: var(--danger); }

.task-section, .calendar-panel { padding: clamp(1rem, 3vw, 1.5rem); background: rgba(15, 21, 17, .86); border: 1px solid var(--line); border-radius: var(--radius); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 1rem; padding-bottom: 1rem; border-bottom: 1px solid var(--line); }
.section-heading p { margin: 0; color: var(--muted); font-size: .78rem; }
.task-list { display: grid; gap: .6rem; padding: 1rem 0 0; margin: 0; list-style: none; }
.task-item { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: .8rem; min-height: 62px; padding: .7rem .8rem; background: #0a0e0b; border: 1px solid var(--line); border-radius: 11px; }
.task-item:hover { border-color: #415348; }
.task-item.completed .task-name { color: var(--muted); text-decoration: line-through; }
.check-control { display: grid; place-items: center; cursor: pointer; }
.task-check { position: absolute; opacity: 0; pointer-events: none; }
.check-box { display: grid; place-items: center; width: 24px; height: 24px; color: #07100a; border: 1px solid #526159; border-radius: 6px; }
.task-check:focus-visible + .check-box { outline: 2px solid var(--accent); outline-offset: 3px; }
.task-check:checked + .check-box { background: var(--accent); border-color: var(--accent); }
.task-check:checked + .check-box::after { content: "✓"; font-weight: 900; }
.task-name { min-width: 0; padding: .4rem 0; color: var(--text); background: none; border: 0; cursor: pointer; text-align: left; }
.task-actions { display: flex; gap: .35rem; }
.action-button { min-height: 34px; padding: .35rem .55rem; color: var(--muted); background: transparent; border: 1px solid var(--line); border-radius: 7px; cursor: pointer; font-size: .72rem; }
.action-button:hover { color: var(--text); border-color: #516258; }
.delete-button:hover { color: var(--danger); border-color: var(--danger); }
.edit-form { display: grid; grid-column: 2 / -1; grid-template-columns: minmax(0, 1fr) auto auto; gap: .45rem; }
.edit-input { width: 100%; min-height: 38px; padding: .5rem .7rem; color: var(--text); background: var(--surface); border: 1px solid var(--accent); border-radius: 7px; outline: 0; }
.empty-state { padding: 3rem 1rem; color: var(--muted); text-align: center; }
.empty-state[hidden] { display: none; }
.empty-state > span { color: var(--accent); font: 1.7rem var(--mono); }
.empty-state h3 { margin: .55rem 0 .2rem; color: var(--text); }
.empty-state p { margin: 0; }

.detail-view[hidden] { display: none; }
.back-button { margin-bottom: 2rem; }
.progress-card { display: flex; align-items: center; gap: 1rem; padding: 1rem; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); }
.progress-card strong, .progress-card span { display: block; }
.progress-card strong { margin-bottom: .2rem; }
.progress-card span { color: var(--muted); font-size: .78rem; }
.progress-ring { --progress: 0deg; position: relative; display: grid; place-items: center; width: 90px; height: 90px; flex: 0 0 auto; background: conic-gradient(var(--accent) var(--progress), var(--line) 0); border-radius: 50%; }
.progress-ring::before { content: ""; position: absolute; width: 68px; height: 68px; background: var(--surface); border-radius: 50%; }
.progress-ring span { position: relative; z-index: 1; color: var(--text); font: 800 1rem var(--mono); }
.weekday-row, .calendar-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: .45rem; }
.weekday-row { padding: 1rem 0 .55rem; color: var(--muted); text-align: center; font: .67rem var(--mono); text-transform: uppercase; }
.calendar-grid { min-height: 340px; }
.date-spacer { min-height: 62px; }
.date-button { min-height: 62px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: .2rem; color: var(--muted); background: #0a0e0b; border: 1px solid var(--line); border-radius: 9px; cursor: pointer; font: .75rem var(--mono); }
.date-button::after { content: ""; width: 5px; height: 5px; background: transparent; border-radius: 50%; }
.date-button.completed { color: var(--text); background: rgba(var(--accent-rgb), .12); border-color: var(--accent); }
.date-button.completed::after { background: var(--accent); box-shadow: 0 0 8px var(--accent); }
.date-button:disabled { cursor: not-allowed; opacity: .3; }
.date-button.today { box-shadow: inset 0 0 0 1px var(--accent); }

.app-footer { border-top: 1px solid var(--line); border-bottom: 0; color: var(--muted); font: .7rem var(--mono); }
.app-footer p { margin: 0; }
.theme-switcher { display: flex; gap: .45rem; }
.theme-button { width: 24px; height: 24px; padding: 0; background: var(--button-color); border: 4px solid var(--bg); border-radius: 50%; box-shadow: 0 0 0 1px var(--line); cursor: pointer; }
.theme-button[data-theme="green"] { --button-color: #65e890; }
.theme-button[data-theme="blue"] { --button-color: #6dbbff; }
.theme-button[data-theme="amber"] { --button-color: #f5bd61; }
.theme-button.active { box-shadow: 0 0 0 2px var(--button-color); }

@media (max-width: 780px) {
  .hero-row, .detail-heading { grid-template-columns: 1fr; }
  .task-form { grid-template-columns: 1fr; }
  .calendar-grid { min-height: 280px; }
  .date-button, .date-spacer { min-height: 48px; }
}

@media (max-width: 560px) {
  .app-shell { width: calc(100% - 1.25rem); }
  .system-status { display: none; }
  main { padding-top: 2rem; }
  h1 { font-size: clamp(2.6rem, 14vw, 4rem); }
  .toolbar { align-items: flex-start; flex-direction: column; }
  .filters { width: 100%; }
  .filter-button { flex: 1; }
  .task-item { grid-template-columns: auto minmax(0, 1fr); }
  .task-actions { grid-column: 2; }
  .edit-form { grid-column: 2; grid-template-columns: 1fr 1fr; }
  .edit-input { grid-column: 1 / -1; }
  .weekday-row, .calendar-grid { gap: .25rem; }
  .date-button, .date-spacer { min-height: 42px; }
  .app-footer { align-items: flex-start; flex-direction: column; justify-content: center; padding-block: 1rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}