/* Shared navigation, controls and support. Keep routine interactions immediate. */
:root { --ease-out: cubic-bezier(0.23, 1, 0.32, 1); --cookie-height: 0px; --text-muted: #a59f96; }
[hidden] { display: none !important; }
.nav { padding-inline: 1.5rem; }
.nav-inner { max-width: 1080px; min-height: 68px; height: auto; gap: 1rem; }
.nav-brand { flex-shrink: 0; font-size: 1.5rem; }
.nav-brand svg { color: var(--accent); }
.nav-links { gap: .2rem; min-width: 0; }
.nav-links a, .nav-account summary { display: flex; align-items: center; min-height: 44px; padding: .55rem .8rem; white-space: nowrap; transition: color 160ms ease, background-color 160ms ease; }
.nav-links a[aria-current="page"] { color: var(--accent); background: var(--accent-subtle); }
.nav-links .nav-login { border: 1px solid var(--border); color: var(--text); }
.nav-account { position: relative; margin-left: .5rem; }
.nav-account summary { gap: .6rem; max-width: 185px; border: 1px solid var(--border); border-radius: 8px; cursor: pointer; color: var(--text-secondary); font-size: .85rem; list-style: none; }
.nav-account summary::-webkit-details-marker { display: none; }
.nav-account summary span { min-width: 0; overflow: hidden; text-overflow: ellipsis; }
.nav-account summary svg { flex-shrink: 0; }
.nav-account[open] summary { border-color: var(--accent); color: var(--accent); }
.nav-account-links { position: absolute; top: calc(100% + 10px); right: 0; width: 240px; padding: .45rem; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; box-shadow: var(--shadow-md); }
.nav-account-links a { color: var(--text-secondary); }
.nav-account-links .nav-signout { margin-top: .25rem; border-top: 1px solid var(--border-subtle); border-radius: 0 0 6px 6px; }
.nav-toggle { width: 44px; height: 44px; }
.nav-toggle-bar { transition: none; }
.main { padding-top: 2.5rem; }
.footer { padding-bottom: calc(5rem + var(--cookie-height)); }
.footer p { max-width: 760px; margin-inline: auto; line-height: 2.2; }
.btn, .affiliate-button { justify-content: center; min-height: 44px; transition: color 160ms ease, background-color 160ms ease, border-color 160ms ease, transform 120ms var(--ease-out); }
.btn:active:not(:disabled):not(:focus-visible), .affiliate-button:active:not(:disabled):not(:focus-visible) { transform: scale(.97); }
.btn:disabled, .affiliate-button:disabled { transform: none; }
.btn-primary:hover { transform: none; box-shadow: none; }
.hero, .topic-card { animation: none; }
.hero { padding: 2.5rem 0 3rem; }
.hero h1 { font-size: clamp(2rem, 5vw, 3.2rem); text-wrap: balance; }
.hero-sub { color: var(--text-secondary); font-weight: 400; }
.topic-input { min-width: 0; }
.topic-card { transition: border-color 160ms ease, background-color 160ms ease, transform 120ms var(--ease-out); }
.topic-card:hover { transform: none; box-shadow: none; }
.sample-topic-card { height: 100%; }
.curriculum-options summary { min-height: 32px; display: list-item; }
.lesson-step { scroll-margin-top: 84px; }
.lesson-step.step-visible { animation: none; }
.lesson-progress .progress-fill { transition: none; }

#help-bot-toggle { position: fixed; right: 24px; bottom: calc(20px + var(--cookie-height) + env(safe-area-inset-bottom)); z-index: 9998; display: flex; align-items: center; justify-content: center; gap: .45rem; min-height: 48px; padding: .6rem .9rem; border: 1px solid var(--border); border-radius: 999px; background: var(--surface); color: var(--accent); box-shadow: var(--shadow-sm); font: inherit; font-size: .85rem; font-weight: 600; cursor: pointer; transition: border-color 160ms ease; }
#help-bot-toggle[aria-expanded="true"] { border-color: var(--accent); }
#help-bot-panel { position: fixed; bottom: calc(82px + var(--cookie-height) + env(safe-area-inset-bottom)); right: 24px; width: min(380px, calc(100vw - 32px)); max-height: min(560px, calc(100dvh - 108px - var(--cookie-height))); display: flex; flex-direction: column; overflow: hidden; background: var(--surface); border: 1px solid var(--border); border-radius: 16px; box-shadow: 0 12px 48px rgba(0,0,0,.35); z-index: 9997; }
.help-bot-header { display: flex; align-items: center; justify-content: space-between; gap: .6rem; border-bottom: 1px solid var(--border-subtle); padding: .7rem 1rem; }
.help-bot-header strong { display: block; font-size: .95rem; }
.help-bot-header a { display: block; font-size: .8rem; }
#help-bot-close { display: grid; place-items: center; width: 44px; height: 44px; flex-shrink: 0; border: 0; border-radius: 8px; background: transparent; color: var(--text-secondary); cursor: pointer; }
#help-bot-panel form { flex-shrink: 0; }
#help-bot-question { min-width: 0; }
#help-bot-thread { overscroll-behavior: contain; }
#cookie-notice { position: fixed; inset: auto 0 0; background: var(--surface); border-top: 1px solid var(--border); padding: .8rem 1.25rem calc(.8rem + env(safe-area-inset-bottom)); z-index: 9996; font-size: .8rem; }
.cookie-notice-inner { max-width: 1000px; margin: 0 auto; display: flex; align-items: center; gap: 1.2rem; }
.cookie-notice-inner p { flex: 1; color: var(--text-secondary); line-height: 1.55; margin: 0; }
#cookie-notice-dismiss { min-height: 44px; padding: .5rem 1rem; flex-shrink: 0; border: 1px solid var(--border); border-radius: 8px; background: transparent; color: var(--text); cursor: pointer; font: inherit; }

@media (hover: hover) and (pointer: fine) {
    .topic-card:hover { border-color: var(--accent); background: var(--surface-hover); }
    #help-bot-toggle:hover { border-color: var(--accent); }
    #help-bot-close:hover, #cookie-notice-dismiss:hover { background: var(--surface-hover); }
    .sample-topic-card:active:not(:focus-visible) { transform: scale(.98); }
}
@media (hover: none), (pointer: coarse) {
    .topic-card:hover { background: var(--surface); border-color: var(--border); }
    .topic-card:hover::before { opacity: 0; }
    .btn-primary:hover { background: var(--accent); }
}
@media (max-width: 960px) {
    .nav { padding-inline: 1rem; }
    .nav-toggle { display: flex; }
    .nav-links { display: none; position: absolute; top: 100%; left: 0; right: 0; padding: .65rem 1rem 1rem; flex-direction: column; align-items: stretch; background: var(--bg-warm); border-bottom: 1px solid var(--border); box-shadow: var(--shadow-md); max-height: calc(100dvh - 68px); overflow-y: auto; overscroll-behavior: contain; }
    .nav-links.open { display: flex; }
    .nav-links a { min-height: 46px; padding-inline: .85rem; font-size: .95rem; }
    .nav-account { margin: .5rem 0 0; padding-top: .5rem; border-top: 1px solid var(--border-subtle); }
    .nav-account summary { max-width: none; font-size: .95rem; justify-content: space-between; }
    .nav-account-links { position: static; width: auto; box-shadow: none; border: none; background: transparent; padding: .25rem 0 0; }
}
@media (max-width: 640px) {
    .main { padding-top: 1.5rem; }
    .input-group { flex-direction: column; gap: .25rem; }
    .input-group .btn { width: 100%; }
    .topic-input { width: 100%; }
    input:not([type="hidden"]):not([type="checkbox"]):not([type="radio"]), select, textarea { font-size: 16px !important; }
    #help-bot-toggle { right: 16px; }
    #help-bot-panel { right: 16px; }
    .cookie-notice-inner { gap: .6rem; align-items: flex-start; }
    #cookie-notice { padding-inline: 1rem; }
}
@media (prefers-reduced-motion: reduce) {
    .btn:active, .affiliate-button:active, .sample-topic-card:active { transform: none !important; }
    .btn, .affiliate-button, .topic-card { transition-property: color, background-color, border-color; }
    .lesson-step { animation: none !important; }
}