/* Shawn AI — Education. Minimalist light theme: neutral palette, one
   accent color, restrained motion. Deliberately not the dark/multi-color
   admin-CMS look used elsewhere — this is a student-facing product. */

:root {
  --bg: #ffffff;
  --bg-soft: #f7f7f8;
  --panel: #ffffff;
  --panel-2: #f7f7f8;
  --border: #e6e6e9;
  --text: #17181c;
  --muted: #6b6f7b;
  --accent: #3a3fc9;
  --accent-soft: #eef0fd;
  --radius: 16px;
  --shadow: 0 12px 32px rgba(20,20,30,0.06);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Plus Jakarta Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
h1, h2, h3 { font-family: "Fraunces", Georgia, serif; font-weight: 400; letter-spacing: -0.01em; }
svg { display: block; }

/* ── Nav / footer ─────────────────────────────────────────────────── */
.edu-nav {
  display: flex; align-items: center; justify-content: space-between;
  padding: 20px 32px; max-width: 1180px; margin: 0 auto;
  position: relative; z-index: 20;
}
.edu-brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 16px; color: var(--text); }
.edu-brand em { font-style: normal; color: var(--accent); font-weight: 700; }
.edu-nav-links { display: flex; align-items: center; gap: 24px; font-size: 14px; color: var(--muted); }
.edu-nav-links a:hover, .edu-nav-links a.active { color: var(--text); }
.edu-nav-cta {
  background: var(--accent); color: #fff !important; padding: 9px 18px; border-radius: 999px; font-weight: 600;
}
.edu-nav-cta:hover { opacity: 0.9; }

.edu-footer {
  max-width: 1180px; margin: 40px auto 0; padding: 24px 32px 40px;
  border-top: 1px solid var(--border); color: var(--muted); font-size: 13px;
}

/* ── Hero ─────────────────────────────────────────────────────────── */
.edu-hero {
  position: relative; overflow: hidden;
  padding: 64px 32px 40px;
  max-width: 1180px; margin: 0 auto;
}
/* One quiet shape, not a multi-color blob field — restrained motion, not
   restrained animation: still drifts slowly, just doesn't shout. */
.blob { position: absolute; border-radius: 50%; z-index: 0; animation: drift 26s ease-in-out infinite; }
.blob-a {
  width: 560px; height: 560px; top: -220px; right: -220px;
  background: radial-gradient(circle, var(--accent-soft), transparent 70%);
}
@keyframes drift {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(-30px, 30px) scale(1.06); }
}
.blob-b, .blob-c { display: none; }
.grid-glow { display: none; }

/* Hero: left copy + right visual, asymmetric split by design (a fixed-width
   visual column anchors the eye after the copy, rather than two equal
   halves competing for attention). */
.edu-hero-row {
  position: relative; z-index: 2; display: flex; align-items: center;
  justify-content: space-between; gap: 40px; flex-wrap: wrap;
}
.edu-hero-inner { max-width: 560px; }
.edu-kicker { color: var(--accent); font-size: 13px; font-weight: 600; letter-spacing: 0.02em; margin: 0 0 16px; }
.edu-hero-title { font-size: clamp(38px, 5vw, 56px); line-height: 1.1; margin: 0 0 20px; color: var(--text); }
.grad-text { color: var(--accent); }
.edu-hero-sub { color: var(--muted); font-size: 17px; line-height: 1.6; max-width: 480px; margin: 0 0 32px; }
.edu-hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }

.btn-edu-primary {
  display: inline-flex; align-items: center; gap: 10px;
  background: var(--accent); color: #fff; padding: 14px 24px; border-radius: 999px;
  font-weight: 600; font-size: 15px;
  transition: transform 0.15s ease, opacity 0.15s ease;
}
.btn-edu-primary:hover { transform: translateY(-2px); opacity: 0.92; }
.btn-edu-primary svg { width: 18px; height: 18px; }
.btn-edu-lg { padding: 17px 30px; font-size: 16px; }
.btn-edu-ghost {
  display: inline-flex; align-items: center; padding: 14px 22px; border-radius: 999px;
  border: 1px solid var(--border); color: var(--text); font-size: 15px; font-weight: 500;
  transition: border-color 0.15s ease, background 0.15s ease;
}
.btn-edu-ghost:hover { border-color: var(--accent); background: var(--accent-soft); }

/* Large hand-drawn hero illustration (open book + rising spark + orbiting
   subject glyphs) — there is no image-generation tool available in this
   build, so every visual on this page is hand-coded SVG/CSS; this is the
   most substantial illustration that approach can produce. Sits behind
   the floating mock-chat cards. */
.hero-illustration { position: absolute; top: 50%; left: 50%; width: 440px; height: 440px; transform: translate(-50%, -50%); z-index: 0; }
.illo-backdrop { fill: var(--accent-soft); }
.illo-ring { fill: none; stroke: var(--border); stroke-width: 1; stroke-dasharray: 4 6; }
.illo-orbit { transform-origin: 220px 220px; animation: illo-spin 50s linear infinite; }
.illo-sat { transform-origin: 220px 220px; }
.illo-sat-1 { transform: translate(220px, 220px) rotate(-40deg) translate(150px) rotate(40deg); }
.illo-sat-2 { transform: translate(220px, 220px) rotate(70deg) translate(150px) rotate(-70deg); }
.illo-sat-3 { transform: translate(220px, 220px) rotate(165deg) translate(150px) rotate(-165deg); }
.illo-sat-4 { transform: translate(220px, 220px) rotate(255deg) translate(150px) rotate(-255deg); }
.illo-sat-bg { fill: var(--bg); stroke: var(--border); stroke-width: 1.5; animation: illo-counter-spin 50s linear infinite; transform-origin: center; }
.illo-sat-glyph { stroke: var(--accent); stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; fill: none; animation: illo-counter-spin 50s linear infinite; transform-origin: center; }
.illo-sat-glyph-fill { fill: var(--accent); animation: illo-counter-spin 50s linear infinite; transform-origin: center; }
@keyframes illo-spin { to { transform: rotate(360deg); } }
@keyframes illo-counter-spin { from { transform: rotate(0deg); } to { transform: rotate(-360deg); } }
.illo-book { fill: var(--panel); stroke: var(--accent); stroke-width: 2; }
.illo-book-spine { stroke: var(--border); stroke-width: 1.5; }
.illo-book-lines { stroke: var(--border); stroke-width: 2; stroke-linecap: round; }
.illo-spark { animation: iconfloat 3.5s ease-in-out infinite; transform-origin: 220px 138px; }
.illo-spark-fill { fill: var(--accent); }

/* Floating mock chat cards, 3D-tilt on hover — two cards, offset stack
   (not three) so the composition reads as a considered pair, not filler. */
.hero-card-stage { position: relative; width: 440px; max-width: 90vw; height: 380px; flex-shrink: 0; perspective: 900px; }
.tilt-card {
  position: absolute; width: 270px; background: var(--panel); border: 1px solid var(--border);
  border-radius: 14px; padding: 16px 18px; box-shadow: var(--shadow);
  transition: transform 0.25s ease; animation: float 7s ease-in-out infinite;
}
.card-1 { top: 0; right: 0; animation-delay: 0s; z-index: 2; }
.card-2 { top: 110px; right: 40px; animation-delay: -3.2s; z-index: 1; }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }
.tilt-card-head { display: flex; align-items: center; gap: 8px; font-size: 12px; font-weight: 700; color: var(--accent); margin-bottom: 8px; text-transform: uppercase; letter-spacing: 0.04em; }
.tilt-card-head .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }
.tilt-q { font-size: 13px; color: var(--text); margin: 0 0 8px; font-weight: 600; line-height: 1.4; }
.tilt-a { font-size: 12.5px; color: var(--muted); margin: 0; line-height: 1.5; }

/* Stat strip: integrated into the hero's own bottom edge (a border-top
   divider, not a separate floating card) so it reads as part of the hero's
   argument, not a disconnected decoration. Left-aligned to the same grid
   as the hero copy above it. */
.edu-strip {
  position: relative; z-index: 2; display: flex; flex-wrap: wrap; gap: 36px;
  margin-top: 64px; padding-top: 28px; border-top: 1px solid var(--border);
}
.strip-item { text-align: left; }
.strip-n { display: block; font-family: "Fraunces", serif; font-size: 30px; color: var(--text); }
.strip-l { display: block; font-size: 12.5px; color: var(--muted); margin-top: 2px; }
.strip-div { display: none; }

/* ── Shared section scaffold ──────────────────────────────────────── */
.edu-section { max-width: 1100px; margin: 0 auto; padding: 80px 32px; }
.edu-section + .edu-section { padding-top: 0; }
.section-head { max-width: 640px; margin: 0 0 40px; }
.section-eyebrow { display: block; color: var(--accent); font-size: 12.5px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 10px; }
.section-head h2 { font-size: 32px; margin: 0; color: var(--text); }
.section-sub { color: var(--muted); font-size: 15px; margin: 10px 0 0; }

/* ── How it works ─────────────────────────────────────────────────── */
.steps-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; position: relative; }
.steps-row::before {
  content: ""; position: absolute; top: 19px; left: 8%; right: 8%; height: 1px;
  background: var(--border); z-index: 0;
}
.step { position: relative; z-index: 1; }
.step-n {
  display: inline-flex; align-items: center; justify-content: center; width: 38px; height: 38px;
  border-radius: 50%; background: var(--bg); border: 1px solid var(--border); color: var(--accent);
  font-family: "Fraunces", serif; font-size: 16px; margin-bottom: 16px;
}
.step h3 { font-size: 18px; margin: 0 0 8px; color: var(--text); }
.step p { font-size: 14px; color: var(--muted); line-height: 1.6; margin: 0; }

/* ── Real-photo slot: clearly marked so it's obvious this is a
   placeholder, not a finished element — swap for an <img class="edu-photo">
   per the HTML comment above it in edu_landing.html. ────────────────── */
.img-placeholder {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 14px;
  height: 260px; border: 1.5px dashed var(--border); border-radius: var(--radius);
  color: var(--muted); text-align: center; padding: 0 40px;
}
.img-placeholder svg { width: 36px; height: 36px; opacity: 0.6; }
.img-placeholder span { font-size: 13.5px; max-width: 360px; }
.edu-photo { width: 100%; height: 420px; object-fit: cover; border-radius: var(--radius); display: block; }
.edu-photo-sm { height: 280px; }
.photo-credit { font-size: 12px; color: var(--muted); margin: 10px 0 0; text-align: right; }
@media (max-width: 760px) {
  .edu-photo { height: 240px; }
  .edu-photo-sm { height: 200px; }
}

/* ── Live demo window: typewriter loop standing in for real video ──── */
.demo-window {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
}
.demo-bar {
  display: flex; align-items: center; gap: 7px; padding: 14px 18px;
  background: var(--bg-soft); border-bottom: 1px solid var(--border);
}
.demo-dot { width: 9px; height: 9px; border-radius: 50%; background: var(--border); }
.demo-bar-label {
  margin-left: auto; font-size: 12px; font-weight: 700; color: var(--accent);
  text-transform: uppercase; letter-spacing: 0.05em;
}
.demo-body { padding: 32px; min-height: 160px; font-size: 15px; line-height: 1.7; }
.demo-line { display: flex; gap: 12px; margin-bottom: 18px; }
.demo-line:last-child { margin-bottom: 0; }
.demo-role {
  flex-shrink: 0; width: 52px; font-size: 11.5px; font-weight: 700; color: var(--muted);
  text-transform: uppercase; letter-spacing: 0.04em; padding-top: 2px;
}
.demo-q .demo-role { color: var(--text); }
.demo-a .demo-role { color: var(--accent); }
.demo-cursor {
  display: inline-block; width: 2px; height: 16px; background: var(--accent);
  margin-left: 2px; vertical-align: middle; animation: blink 0.9s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* ── FAQ ──────────────────────────────────────────────────────────── */
.faq-list { max-width: 760px; }
.faq-item {
  border-bottom: 1px solid var(--border); padding: 18px 0;
}
.faq-item summary {
  cursor: pointer; font-weight: 600; font-size: 15.5px; color: var(--text);
  list-style: none; display: flex; align-items: center; justify-content: space-between;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+"; color: var(--accent); font-size: 20px; font-weight: 400; flex-shrink: 0; margin-left: 16px;
}
.faq-item[open] summary::after { content: "−"; }
.faq-item p { color: var(--muted); font-size: 14.5px; line-height: 1.6; margin: 12px 0 0; }

/* ── Features: bento grid — one emphasized card carries the main claim,
   three smaller ones support it, instead of four equal, interchangeable
   boxes. ─────────────────────────────────────────────────────────── */
.bento-grid { display: grid; grid-template-columns: repeat(3, 1fr); grid-auto-rows: minmax(160px, auto); gap: 16px; }
.bento-card {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px; transition: transform 0.2s ease, border-color 0.2s ease;
}
.bento-card:hover { transform: translateY(-4px); border-color: var(--accent); }
.bento-lg { grid-column: span 2; grid-row: span 2; display: flex; flex-direction: column; justify-content: flex-end; }
.bento-lg h3 { font-size: 23px; }
.bento-lg p { font-size: 15px; max-width: 420px; }
.bento-wide { grid-column: span 2; }
.feature-icon {
  width: 44px; height: 44px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  background: var(--accent-soft); color: var(--accent); margin-bottom: 16px;
}
.feature-icon svg { width: 22px; height: 22px; }
.icon-anim-spin svg { animation: spin 9s linear infinite; }
.icon-anim-pulse svg { animation: pulse 2.4s ease-in-out infinite; }
.icon-anim-float svg { animation: iconfloat 3s ease-in-out infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
@keyframes pulse { 0%, 100% { transform: scale(1); opacity: 1; } 50% { transform: scale(1.1); opacity: 0.7; } }
@keyframes iconfloat { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-3px); } }
.bento-card h3 { font-size: 18px; margin: 0 0 8px; color: var(--text); }
.bento-card p { font-size: 14px; color: var(--muted); line-height: 1.6; margin: 0; }

/* ── Subjects: grouped by category (chunking, not one flat 13-item grid)
   so a visitor can scan "is my subject here" in one pass. ──────────── */
.subject-group { margin-bottom: 32px; }
.subject-group:last-child { margin-bottom: 0; }
.subject-group-label {
  font-size: 12px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--muted); margin: 0 0 14px;
}
.subject-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 12px; }
.subject-card {
  display: flex; align-items: center; gap: 12px;
  background: var(--panel); border: 1px solid var(--border); border-radius: 12px;
  padding: 14px 16px; font-size: 13.5px; font-weight: 600; color: var(--text);
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}
.subject-card svg { width: 20px; height: 20px; color: var(--muted); flex-shrink: 0; transition: color 0.2s ease; }
.subject-card:hover { transform: translateY(-2px); border-color: var(--accent); background: var(--accent-soft); }
.subject-card:hover svg { color: var(--accent); }

/* ── CTA: the one deliberately centered, symmetric moment on the page —
   a closing beat after everything else follows the left-aligned grid. ── */
.edu-cta {
  max-width: 700px; margin: 40px auto 100px; padding: 60px 32px; text-align: center;
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: 24px;
}
.edu-cta h2 { font-size: 32px; margin: 0 0 10px; color: var(--text); }
.edu-cta p { color: var(--muted); margin: 0 0 26px; }

@media (max-width: 760px) {
  .bento-lg, .bento-wide { grid-column: span 3; }
  .bento-grid { grid-template-columns: 1fr; }
  .bento-lg, .bento-wide { grid-column: span 1; grid-row: span 1; }
  .steps-row { grid-template-columns: 1fr; gap: 32px; }
  .steps-row::before { display: none; }
  .hero-card-stage { display: none; }
}

/* ══════════════════════════════════════════════════════════════════
   Tutor chat page
   ══════════════════════════════════════════════════════════════════ */
.tutor-shell { display: flex; max-width: 1180px; margin: 0 auto; padding: 0 24px 24px; gap: 20px; height: calc(100vh - 76px); }

.history-sidebar {
  width: 240px; flex-shrink: 0; background: var(--bg-soft); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 14px; display: flex; flex-direction: column; gap: 10px;
  overflow-y: auto;
}
.history-new-btn {
  display: flex; align-items: center; gap: 8px; padding: 10px 12px; border-radius: 10px;
  border: 1px dashed var(--border); background: transparent; color: var(--text);
  font-size: 13.5px; font-weight: 600; cursor: pointer;
}
.history-new-btn:hover { border-color: var(--accent); color: var(--accent); }
.history-new-btn svg { width: 16px; height: 16px; }
.history-list { display: flex; flex-direction: column; gap: 4px; }
.history-empty { color: var(--muted); font-size: 12.5px; padding: 8px 4px; }
.history-item {
  display: flex; align-items: center; gap: 6px; width: 100%; text-align: left;
  background: transparent; border: none; border-radius: 8px; padding: 9px 10px; cursor: pointer;
  color: var(--muted); font-size: 13px;
}
.history-item:hover, .history-item.active { background: #ffffff; color: var(--text); }
.history-item-title { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.history-item-time { font-size: 11px; color: var(--muted); flex-shrink: 0; }
.history-item-delete { opacity: 0; width: 16px; height: 16px; flex-shrink: 0; }
.history-item:hover .history-item-delete { opacity: 0.6; }
.history-item-delete:hover { opacity: 1 !important; color: #c23b3b; }

/* ── Account / sign-in (sidebar footer) ──────────────────────────── */
.history-account { margin-top: auto; padding-top: 10px; border-top: 1px solid var(--border); }
.history-account-btn {
  width: 100%; padding: 9px 10px; border-radius: 10px; border: 1px solid var(--border);
  background: transparent; color: var(--accent); font-size: 12.5px; font-weight: 600; cursor: pointer;
}
.history-account-btn:hover { border-color: var(--accent); background: var(--accent-soft); }
.history-account-chip { display: flex; align-items: center; justify-content: space-between; gap: 8px; padding: 4px 2px; }
.history-account-email { font-size: 12px; color: var(--text); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.history-account-logout {
  flex-shrink: 0; background: transparent; border: none; color: var(--muted);
  font-size: 11.5px; cursor: pointer; text-decoration: underline;
}
.history-account-logout:hover { color: var(--text); }
.edu-login-form { display: flex; flex-direction: column; gap: 8px; }
.edu-login-form input {
  width: 100%; padding: 9px 10px; border-radius: 8px; border: 1px solid var(--border);
  background: #fff; color: var(--text); font-size: 13px; font-family: inherit;
}
.edu-login-form input:focus { outline: none; border-color: var(--accent); }
.edu-login-form button {
  padding: 8px 10px; border-radius: 8px; border: none; background: var(--accent);
  color: #fff; font-size: 12.5px; font-weight: 600; cursor: pointer;
}
.edu-login-form button:hover { opacity: 0.9; }
.edu-login-sub { font-size: 11.5px; color: var(--muted); margin: 0; }
.edu-login-msg { font-size: 11.5px; color: var(--muted); margin: 0; min-height: 14px; }

.chat-shell { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.chat-top { display: flex; align-items: center; gap: 14px; padding: 4px 0 16px; border-bottom: 1px solid var(--border); margin-bottom: 8px; }
.history-toggle { display: none; background: var(--bg-soft); border: 1px solid var(--border); border-radius: 8px; width: 34px; height: 34px; align-items: center; justify-content: center; color: var(--text); cursor: pointer; }
.chat-top-copy { flex: 1; }
.chat-top-kicker { font-size: 12px; color: var(--accent); font-weight: 600; margin: 0 0 4px; }
.chat-top-title { font-size: 24px; margin: 0; color: var(--text); }
.chat-top-hint { font-size: 12.5px; color: var(--muted); margin: 0; }

.chat-log { flex: 1; overflow-y: auto; padding: 8px 4px 20px; display: flex; flex-direction: column; gap: 18px; }
.chat-empty { margin: auto; text-align: center; max-width: 480px; padding: 40px 20px; }
.chat-empty-icon { width: 44px; height: 44px; margin: 0 auto 16px; color: var(--accent); }
.chat-empty-icon svg { width: 100%; height: 100%; animation: pulse 2.4s ease-in-out infinite; }
.chat-empty-title { font-size: 19px; margin: 0 0 8px; font-family: "Fraunces", serif; color: var(--text); }
.chat-empty-sub { font-size: 13.5px; color: var(--muted); line-height: 1.6; margin: 0 0 20px; }
.chat-empty-chips { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; }
.chat-empty-chip {
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: 999px;
  padding: 8px 14px; font-size: 12.5px; color: var(--text); cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease;
}
.chat-empty-chip:hover { border-color: var(--accent); background: var(--accent-soft); }

.msg { display: flex; gap: 12px; max-width: 720px; }
.msg.user { align-self: flex-end; flex-direction: row-reverse; }
.avatar {
  width: 30px; height: 30px; border-radius: 50%; flex-shrink: 0; display: flex; align-items: center;
  justify-content: center; font-size: 12px; font-weight: 700; background: var(--accent); color: #fff;
}
.msg.user .avatar { background: var(--bg-soft); color: var(--text); border: 1px solid var(--border); }
.msg-body { min-width: 0; }
.who { font-size: 11.5px; color: var(--muted); margin-bottom: 4px; font-weight: 600; }
.msg.user .who { text-align: right; }
.bubble {
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: 14px; padding: 12px 16px;
  font-size: 14.5px; line-height: 1.6; white-space: pre-wrap; word-wrap: break-word; color: var(--text);
}
.msg.user .bubble { background: var(--accent-soft); }
.bubble.pending { color: var(--muted); font-style: italic; }

.symbol-toolbar { display: flex; flex-wrap: wrap; gap: 6px; padding: 8px 4px; }
.symbol-toolbar button {
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: 8px; color: var(--text);
  font-size: 13px; padding: 6px 10px; cursor: pointer; min-width: 34px;
}
.symbol-toolbar button:hover { border-color: var(--accent); color: var(--accent); }

.chat-input-row { display: flex; gap: 10px; align-items: flex-end; padding: 6px 4px 0; }
.chat-input-row textarea {
  flex: 1; resize: none; background: var(--bg-soft); border: 1px solid var(--border); border-radius: 14px;
  color: var(--text); font-family: inherit; font-size: 14.5px; padding: 12px 16px; max-height: 160px;
}
.chat-input-row textarea:focus { outline: none; border-color: var(--accent); }
.chat-input-row button {
  display: flex; align-items: center; gap: 6px; background: var(--accent);
  color: #fff; border: none; border-radius: 999px; padding: 12px 20px; font-weight: 600; font-size: 14px; cursor: pointer;
  flex-shrink: 0;
}
.chat-input-row button:disabled { opacity: 0.5; cursor: default; }
.chat-input-row button svg { width: 16px; height: 16px; }

@media (max-width: 860px) {
  .tutor-shell { height: auto; min-height: calc(100vh - 76px); }
  .history-sidebar {
    position: fixed; top: 0; left: -280px; bottom: 0; z-index: 50; width: 260px;
    border-radius: 0; transition: left 0.2s ease; box-shadow: var(--shadow);
  }
  .history-sidebar.open { left: 0; }
  .history-toggle { display: flex; }
  .hero-card-stage { display: none; }
  .edu-hero { justify-content: center; text-align: center; }
  .edu-hero-actions { justify-content: center; }
}