/* Deep Chat. Riviera palette (navy, shell, terracotta, sand), Instrument Serif over Instrument Sans. */

@font-face {
  font-family: "Instrument Serif";
  src: url("/fonts/instrument-serif-latin-400-normal.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Instrument Sans";
  src: url("/fonts/instrument-sans-latin-wght-normal.woff2") format("woff2");
  font-weight: 400 700;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Instrument Sans";
  src: url("/fonts/instrument-sans-latin-wght-italic.woff2") format("woff2");
  font-weight: 400 700;
  font-style: italic;
  font-display: swap;
}

:root {
  --bg: #F7F5F0;
  --surface: #EBEAE6;
  --fg: #0B1A2A;
  --fg-2: #5B646D;
  --rule: #D6D6D4;
  --rule-strong: #838A8F;
  --accent: #A84E33;
  --on-accent: #F7F5F0;
  --accent-2: #D8C8A8;
  --scrim: rgb(11 26 42 / 0.45);
  color-scheme: light;

  --font-display: "Instrument Serif", "Iowan Old Style", Georgia, serif;
  --font-text: "Instrument Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  --step--1: clamp(0.8125rem, 0.8rem + 0.06vw, 0.875rem);
  --step-0: clamp(1rem, 0.97rem + 0.15vw, 1.0625rem);
  --step-1: clamp(1.2rem, 1.12rem + 0.35vw, 1.4rem);
  --step-3: clamp(1.836rem, 1.51rem + 1.447vw, 2.813rem);
  --step-4: clamp(2.203rem, 1.688rem + 2.291vw, 3.749rem);

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --gutter: clamp(1rem, 0.3333rem + 2.963vw, 3rem);
  --measure: 46rem;

  --radius: 2px;
  --shadow-overlay: 0 12px 32px rgb(0 0 0 / 0.18);
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-3: 240ms;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0B1A2A;
    --surface: #172534;
    --fg: #F7F5F0;
    --fg-2: #8D9297;
    --rule: #2C3946;
    --rule-strong: #626B73;
    --accent: #D8C8A8;
    --on-accent: #0B1A2A;
    --accent-2: #A84E33;
    --scrim: rgb(0 0 0 / 0.55);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0B1A2A;
  --surface: #172534;
  --fg: #F7F5F0;
  --fg-2: #8D9297;
  --rule: #2C3946;
  --rule-strong: #626B73;
  --accent: #D8C8A8;
  --on-accent: #0B1A2A;
  --accent-2: #A84E33;
  --scrim: rgb(0 0 0 / 0.55);
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 400 var(--step-0)/1.55 var(--font-text);
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
[hidden] { display: none !important; }
button, input, select, textarea { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
input:focus-visible, select:focus-visible, textarea:focus-visible { outline-offset: 0; }
summary { list-style: none; }
summary::-webkit-details-marker { display: none; }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
.num { font-variant-numeric: tabular-nums lining-nums; }
.muted { color: var(--fg-2); }
.small { font-size: var(--step--1); }
.label {
  font: 600 var(--step--1)/1.2 var(--font-text);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fg-2);
}
.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  margin: -1px; padding: 0; border: 0;
  overflow: hidden; clip-path: inset(50%); white-space: nowrap;
}
.skip-link {
  position: absolute; left: var(--space-4); top: -3rem; z-index: 50;
  background: var(--fg); color: var(--bg); padding: var(--space-2) var(--space-4);
}
.skip-link:focus { top: var(--space-4); }
.wordmark { margin: 0; font: 400 1.875rem/1 var(--font-display); letter-spacing: -0.01em; }

/* Controls */
.button {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 2.75rem; padding: 0 var(--space-5);
  border: 1px solid var(--rule-strong); border-radius: var(--radius);
  background: transparent; color: var(--fg);
  font: 600 var(--step--1)/1 var(--font-text); letter-spacing: 0.02em;
  cursor: pointer;
}
.button:hover { border-color: var(--fg); }
.button.primary { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.button.primary:hover { border-color: var(--fg); }
.button:disabled { opacity: 0.55; cursor: not-allowed; }
.text-button {
  display: inline-flex; align-items: center;
  min-height: 2.75rem; padding: 0 var(--space-2);
  background: none; border: 0; cursor: pointer;
  color: var(--fg-2);
  font: 600 var(--step--1)/1 var(--font-text); letter-spacing: 0.02em;
  text-decoration: underline; text-decoration-color: transparent; text-underline-offset: 0.3em;
}
.text-button:hover { color: var(--fg); text-decoration-color: currentColor; }
.icon-button {
  display: inline-grid; place-items: center;
  width: 2.75rem; height: 2.75rem; padding: 0;
  background: none; border: 0; cursor: pointer; color: var(--fg);
}
.icon-button svg { fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; }
.tool-button {
  display: inline-flex; align-items: center; gap: var(--space-2);
  min-height: 2.75rem; padding: 0 var(--space-3);
  background: none; border: 1px solid var(--rule); border-radius: var(--radius);
  color: var(--fg); cursor: pointer;
  font: 600 var(--step--1)/1 var(--font-text); letter-spacing: 0.02em;
}
.tool-button:hover { border-color: var(--rule-strong); }
.tool-button.toggle::before {
  content: ""; width: 0.6rem; height: 0.6rem;
  border: 1px solid currentColor;
}
.tool-button.toggle[aria-pressed="true"] { border-color: var(--fg); }
.tool-button.toggle[aria-pressed="true"]::before { background: currentColor; }
input[type="text"], input[type="password"], input[type="number"], input:not([type]), select, textarea {
  min-height: 2.75rem; width: 100%;
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--rule-strong); border-radius: var(--radius);
  background: var(--bg); color: var(--fg);
}
textarea { line-height: 1.5; resize: vertical; }
select {
  appearance: none; -webkit-appearance: none;
  padding-inline-end: 2rem;
  background-image:
    linear-gradient(45deg, transparent 50%, currentColor 50%),
    linear-gradient(135deg, currentColor 50%, transparent 50%);
  background-position: calc(100% - 1rem) 55%, calc(100% - 0.7rem) 55%;
  background-size: 0.3rem 0.3rem, 0.3rem 0.3rem;
  background-repeat: no-repeat;
  cursor: pointer;
}
input[type="checkbox"], input[type="radio"] { width: 1.15rem; height: 1.15rem; margin: 0; accent-color: var(--accent); }

/* Sign-in */
.login { min-height: 100dvh; display: grid; place-items: center; padding: var(--gutter); }
.login-inner { width: min(27rem, 100%); }
.login-title {
  margin: var(--space-7) 0 var(--space-7);
  font: 400 var(--step-4)/1.06 var(--font-display); letter-spacing: -0.015em; text-wrap: balance;
}
.login-form { display: grid; gap: var(--space-3); }
.login-form .button { justify-self: start; margin-top: var(--space-2); }
.login-note { margin: var(--space-6) 0 0; color: var(--fg-2); font-size: var(--step--1); max-width: 36ch; }
.field-label { font-weight: 600; font-size: var(--step--1); letter-spacing: 0.02em; }
.field-error { margin: 0; color: var(--accent); font-size: var(--step--1); }
.field-error::before { content: "Error: "; font-weight: 600; }

/* Shell */
.shell { display: grid; grid-template-columns: 17.5rem minmax(0, 1fr); height: 100dvh; }
.sidebar {
  display: flex; flex-direction: column; gap: var(--space-4);
  min-height: 0; padding: var(--space-5) var(--space-4) var(--space-3);
  border-inline-end: 1px solid var(--rule); background: var(--bg);
}
.sidebar-head { display: flex; align-items: center; justify-content: space-between; min-height: 2.75rem; }
.new-chat { width: 100%; }
.chat-nav { flex: 1; min-height: 0; overflow-y: auto; margin-inline: calc(var(--space-2) * -1); }
.chat-list { list-style: none; margin: 0; padding: 0; }
.chat-link {
  display: grid; gap: 0.1rem; width: 100%;
  padding: var(--space-2) var(--space-2); min-height: 2.75rem;
  background: none; border: 0; border-inline-start: 2px solid transparent;
  text-align: start; cursor: pointer; color: var(--fg);
}
.chat-link:hover { background: var(--surface); }
.chat-link[aria-current="page"] { border-inline-start-color: var(--accent); background: var(--surface); }
.chat-link-title { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: var(--step--1); font-weight: 600; }
.chat-link-date { font-size: 0.75rem; color: var(--fg-2); }
.sidebar-foot { border-block-start: 1px solid var(--rule); padding-block-start: var(--space-3); }
.balance { margin: 0 0 var(--space-1); display: flex; justify-content: space-between; align-items: baseline; gap: var(--space-3); }
.balance .num { font-weight: 600; }
.balance .num.low { color: var(--accent); }
.foot-actions { display: flex; flex-wrap: wrap; margin-inline: calc(var(--space-2) * -1); }
.scrim { position: fixed; inset: 0; background: var(--scrim); z-index: 10; }

.main { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.topbar {
  display: flex; align-items: center; gap: var(--space-2);
  min-height: 3.5rem; padding: var(--space-1) var(--gutter);
  border-block-end: 1px solid var(--rule);
}
.chat-title {
  flex: 1; min-width: 0; margin: 0;
  font: 600 var(--step-0)/1.3 var(--font-text);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.rename-form { flex: 1; display: flex; gap: var(--space-2); }
.top-actions { display: flex; }

.thread { flex: 1; min-height: 0; overflow-y: auto; padding: var(--space-7) var(--gutter) var(--space-6); }
.turns, .empty { max-width: var(--measure); margin-inline: auto; }
.turns { list-style: none; padding: 0; margin-block: 0; }

/* Empty state: the page's one moment of motion */
.empty { padding-block: clamp(2rem, 12vh, 8rem) var(--space-6); }
.empty-title {
  margin: 0 0 var(--space-5);
  font: 400 var(--step-4)/1.06 var(--font-display); letter-spacing: -0.015em; text-wrap: balance;
}
.rise { animation: rise var(--dur-3) var(--ease-out-expo) both; }
@keyframes rise { from { opacity: 0; transform: translateY(0.35em); } }
.empty-lead { margin: 0; max-width: 52ch; color: var(--fg-2); }
.empty-meta { margin: var(--space-5) 0 0; padding-block-start: var(--space-4); border-block-start: 1px solid var(--rule); color: var(--fg-2); font-size: var(--step--1); }

/* Turns */
.turn { padding-block: var(--space-7); border-block-start: 1px solid var(--rule); }
.turn:first-child { border-block-start: 0; padding-block-start: 0; }
.speaker { display: flex; flex-wrap: wrap; gap: 0 var(--space-3); align-items: baseline; margin: 0 0 var(--space-3); }
.speaker .label + .label::before { content: "·"; margin-inline-end: var(--space-3); }
.status { font-size: var(--step--1); color: var(--fg-2); font-variant-numeric: tabular-nums; }
.ask-text { margin: 0; white-space: pre-wrap; overflow-wrap: anywhere; max-width: 66ch; }
.ask-text.display {
  font: 400 clamp(1.75rem, 1.45rem + 1.1vw, 2.35rem)/1.12 var(--font-display);
  letter-spacing: -0.01em; text-wrap: balance;
}
.ask-files { display: flex; flex-wrap: wrap; gap: var(--space-3); list-style: none; padding: 0; margin: var(--space-4) 0 0; }
.ask-files img { display: block; max-width: 10rem; max-height: 10rem; width: auto; height: auto; border: 1px solid var(--rule); }
.file-chip { display: inline-flex; gap: var(--space-2); align-items: center; padding: var(--space-1) var(--space-3); border: 1px solid var(--rule); font-size: var(--step--1); }
.edit-form { display: grid; gap: var(--space-2); }
.edit-actions { display: flex; gap: var(--space-2); }
.answer { margin-block-start: var(--space-6); }
.actions { display: flex; flex-wrap: wrap; margin: var(--space-2) 0 0 calc(var(--space-2) * -1); }
.meta { margin: var(--space-4) 0 0; color: var(--fg-2); font-size: var(--step--1); font-variant-numeric: tabular-nums lining-nums; }
.note { margin: var(--space-4) 0 0; padding-inline-start: var(--space-3); border-inline-start: 2px solid var(--accent); font-size: var(--step--1); }
.note strong { font-weight: 600; }

.thought { margin: 0 0 var(--space-4); border-inline-start: 1px solid var(--accent-2); padding-inline-start: var(--space-4); }
.thought > summary {
  display: flex; align-items: center; min-height: 2.75rem; width: fit-content;
  cursor: pointer; color: var(--fg-2); font-size: var(--step--1); font-weight: 600; letter-spacing: 0.02em;
  list-style-position: inside;
}
.thought > summary::before, .step > summary::before { content: "+"; display: inline-block; width: 1.1em; font-weight: 400; }
.thought[open] > summary::before, .step[open] > summary::before { content: "\2212"; }
.thought-text { margin: 0 0 var(--space-3); white-space: pre-wrap; overflow-wrap: anywhere; color: var(--fg-2); font-size: 0.94em; line-height: 1.55; }

.step { margin: 0 0 var(--space-3); font-size: var(--step--1); color: var(--fg-2); }
.step > summary { display: flex; align-items: center; min-height: 2.75rem; width: fit-content; cursor: pointer; font-weight: 600; letter-spacing: 0.02em; }
.step ol { margin: 0 0 var(--space-3); padding-inline-start: 1.4rem; }
.step li { margin-block: 0.2rem; }
.step .host { color: var(--fg-2); }

/* Model output */
.md { overflow-wrap: anywhere; }
.md > :first-child { margin-top: 0; }
.md > * + * { margin-top: 0.85em; }
.md p, .md li { max-width: 70ch; }
.md p { margin: 0; }
.md ul, .md ol { margin-block: 0; padding-inline-start: 1.4rem; }
.md li + li { margin-top: 0.3em; }
.md li > ul, .md li > ol { margin-top: 0.3em; }
.md h2, .md h3, .md h4, .md h5, .md h6 { margin: 1.4em 0 0; font-weight: 600; line-height: 1.3; }
.md .md-h1 { font: 400 var(--step-3)/1.1 var(--font-display); letter-spacing: -0.01em; }
.md .md-h2 { font-size: var(--step-1); }
.md .md-h3 { font-size: 1.1em; }
.md .md-h4, .md .md-h5, .md .md-h6 { font-size: 1em; }
.md blockquote { margin-inline: 0; padding-inline-start: var(--space-4); border-inline-start: 1px solid var(--rule-strong); color: var(--fg-2); }
.md hr { border: 0; border-block-start: 1px solid var(--rule); margin-block: 1.6em; }
.md code { font-family: var(--font-mono); font-size: 0.86em; background: var(--surface); padding: 0.1em 0.3em; border-radius: var(--radius); }
.md .code { margin-inline: 0; border: 1px solid var(--rule); background: var(--surface); }
.md .code figcaption {
  display: flex; justify-content: space-between; align-items: center;
  padding: 0 var(--space-2) 0 var(--space-3); border-block-end: 1px solid var(--rule);
}
.code-lang { font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--fg-2); font-weight: 600; }
.copy-code {
  min-height: 2.75rem; padding: 0 var(--space-2);
  background: none; border: 0; cursor: pointer; color: var(--fg-2);
  font: 600 0.75rem/1 var(--font-text); letter-spacing: 0.08em; text-transform: uppercase;
}
.copy-code:hover { color: var(--fg); }
.md pre { margin: 0; padding: var(--space-3); overflow-x: auto; font-size: 0.86em; line-height: 1.5; }
.md pre code { background: none; padding: 0; font-size: 1em; }
.md pre.math, .md code.math { font-family: var(--font-mono); white-space: pre-wrap; }
.md pre.math { border: 1px solid var(--rule); }
.table-wrap { overflow-x: auto; }
.md table { border-collapse: collapse; font-size: 0.94em; font-variant-numeric: tabular-nums lining-nums; }
.md th, .md td { padding: var(--space-2) var(--space-3); border-block-end: 1px solid var(--rule); text-align: start; vertical-align: top; }
.md th { font-weight: 600; border-block-end-color: var(--rule-strong); }
.md .align-right { text-align: end; }
.md .align-center { text-align: center; }

/* Composer */
.composer { padding: var(--space-3) var(--gutter) max(var(--space-3), env(safe-area-inset-bottom)); border-block-start: 1px solid var(--rule); background: var(--bg); }
.composer > * { max-width: var(--measure); margin-inline: auto; }
.composer textarea { display: block; resize: none; min-height: 3.25rem; max-height: 40dvh; padding: var(--space-3); }
.composer-bar { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2); margin-top: var(--space-2); }
.bar-spacer { flex: 1; }
.select-wrap { display: inline-flex; align-items: center; gap: var(--space-2); }
.select-wrap select { width: auto; font-size: var(--step--1); font-weight: 600; }
.select-label { font-size: var(--step--1); color: var(--fg-2); font-weight: 600; }
.composer-note { margin: 0 auto var(--space-2); font-size: var(--step--1); padding-inline-start: var(--space-3); border-inline-start: 2px solid var(--accent); }
.attachments { display: flex; flex-wrap: wrap; gap: var(--space-2); list-style: none; padding: 0; margin-block: 0 var(--space-2); }
.attachment { display: flex; align-items: center; gap: var(--space-2); max-width: 100%; padding-inline-start: var(--space-1); border: 1px solid var(--rule); font-size: var(--step--1); }
.attachment img { width: 2.25rem; height: 2.25rem; object-fit: cover; display: block; }
.attachment-name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; max-width: 14rem; }
.attachment-state { color: var(--fg-2); }

/* Dialogs */
dialog.sheet {
  padding: 0; border: 0; border-inline-start: 1px solid var(--rule);
  width: min(34rem, 100vw); max-width: 100vw; height: 100dvh; max-height: 100dvh;
  margin: 0 0 0 auto; background: var(--bg); color: var(--fg);
  box-shadow: var(--shadow-overlay);
}
dialog.sheet::backdrop { background: var(--scrim); }
dialog.sheet.small { height: auto; margin: auto; width: min(26rem, calc(100vw - 2rem)); border: 1px solid var(--rule); }
.settings { padding: 0 var(--gutter) var(--space-7); }
.sheet-head {
  position: sticky; top: 0; z-index: 1; display: flex; align-items: center; justify-content: space-between;
  padding-block: var(--space-4); background: var(--bg); border-block-end: 1px solid var(--rule);
}
.sheet-title { margin: 0; font: 400 1.875rem/1.1 var(--font-display); letter-spacing: -0.01em; }
.sheet-intro { color: var(--fg-2); font-size: var(--step--1); margin: var(--space-4) 0 var(--space-5); }
.field { display: grid; gap: var(--space-2); margin: 0 0 var(--space-5); padding: 0; border: 0; min-width: 0; }
.field.check { grid-template-columns: auto 1fr; align-items: center; column-gap: var(--space-3); }
.field.check .hint { grid-column: 2; }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
.hint { margin: 0; color: var(--fg-2); font-size: var(--step--1); }
.model-options { display: grid; gap: var(--space-2); }
.model-option { display: grid; grid-template-columns: auto 1fr; gap: 0 var(--space-3); align-items: start; padding: var(--space-3); border: 1px solid var(--rule); cursor: pointer; }
.model-option:has(input:checked) { border-color: var(--fg); }
.model-option input { margin-top: 0.3rem; }
.model-name { font-weight: 600; }
.model-facts { grid-column: 2; color: var(--fg-2); font-size: var(--step--1); font-variant-numeric: tabular-nums lining-nums; }
.confirm { padding: var(--space-5); }
.confirm-body { color: var(--fg-2); margin: var(--space-3) 0 var(--space-5); }
.confirm-actions { display: flex; justify-content: flex-end; gap: var(--space-2); }

/* Phone and tablet */
@media (max-width: 63.99rem) {
  .shell { grid-template-columns: minmax(0, 1fr); }
  .sidebar {
    position: fixed; inset: 0 auto 0 0; z-index: 20; width: min(20rem, 86vw);
    display: none; box-shadow: var(--shadow-overlay);
  }
  .shell.nav-open .sidebar { display: flex; }
  .thread { padding-block-start: var(--space-6); }
  .field-row { grid-template-columns: 1fr; gap: 0; }
}
@media (min-width: 64rem) {
  .only-narrow { display: none !important; }
  .scrim { display: none !important; }
}
@media (max-width: 30rem) {
  .select-label { display: none; }
  .top-actions .text-button { padding-inline: var(--space-1); }
  .turn { padding-block: var(--space-6); }
}

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