:root{color:#183427;font-synthesis:none;text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:#eff4ea}*{box-sizing:border-box}html{overscroll-behavior:none;min-width:320px;height:100%;min-height:100%;overflow:hidden}body{overscroll-behavior:none;min-width:320px;height:100%;min-height:100%;margin:0;overflow:hidden}button,input{font:inherit}:root{--chat-bg-top:#d9e6d5;--chat-bg-bottom:#eff4ea;--shell-bg:#f8f4eceb;--shell-border:#3e564324;--header-bg:#edf1e9f2;--thread-bg:#e7efe6;--text-main:#183427;--text-soft:#5f6f65;--bot-bubble:#fffdf8;--user-bubble:#d8f2c8;--correct-bubble:#cceeb8;--incorrect-bubble:#fff0cf;--system-bubble:#ffe1d7;--composer-bg:#f4f0e8f5;--composer-field:#fffdf8;--composer-border:#c8d2c0;--send-start:#2d8f57;--send-end:#1d6f43;--shadow-soft:0 20px 60px #24392929;--shadow-bubble:0 10px 20px #1d2b2114}#root{height:100%;min-height:100%}.chat-app{top:var(--visual-viewport-offset-top,0px);height:var(--visual-viewport-height,100dvh);background:radial-gradient(circle at top left, #ffffff80, transparent 32%), linear-gradient(180deg, var(--chat-bg-top) 0%, var(--chat-bg-bottom) 100%);color:var(--text-main);justify-content:center;font-family:SF Pro Text,Segoe UI,Helvetica Neue,Trebuchet MS,sans-serif;display:flex;position:fixed;left:0;right:0;overflow:hidden}.chat-shell{background:var(--shell-bg);grid-template-rows:auto 1fr auto;width:100%;height:100%;min-height:0;display:grid;overflow:hidden}.chat-header{padding:calc(.95rem + env(safe-area-inset-top)) 1rem .95rem;background:var(--header-bg);border-bottom:1px solid var(--shell-border);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);align-items:center;gap:.85rem;display:flex}.chat-avatar{letter-spacing:.04em;color:#f6fff7;background:linear-gradient(135deg,#2c7a4e 0%,#4ca26f 100%);border-radius:999px;flex-shrink:0;place-items:center;width:2.9rem;height:2.9rem;font-size:.95rem;font-weight:700;display:grid;box-shadow:inset 0 1px #ffffff59}.chat-header-copy{min-width:0}.chat-title,.chat-subtitle{margin:0}.chat-title{font-size:1rem;font-weight:700}.chat-subtitle{color:var(--text-soft);margin-top:.15rem;font-size:.84rem}.chat-thread{overscroll-behavior:contain;background:radial-gradient(circle at 1px 1px, #4a654e1a 1px, transparent 0) 0 0 / 24px 24px, linear-gradient(180deg, #e9f0e7 0%, var(--thread-bg) 100%);flex-direction:column;gap:.8rem;min-height:0;padding:1rem;display:flex;overflow-y:auto}.chat-empty{color:var(--text-soft);box-shadow:var(--shadow-bubble);background:#fffdf8e0;border-radius:1rem;margin:auto;padding:.9rem 1.1rem}.chat-error-state{text-align:center;max-width:min(92%,28rem);box-shadow:var(--shadow-bubble);background:#fff8f6;border-radius:1.2rem;margin:auto;padding:1rem}.chat-error-state p{margin:0}.chat-error-state p+p{color:#9c4f3f;margin-top:.45rem}.chat-error-state button{margin-top:.9rem}.message{max-width:min(80%,34rem);box-shadow:var(--shadow-bubble);border-radius:1.2rem;padding:.8rem .95rem .45rem}.message-bot{background:var(--bot-bubble);border-top-left-radius:.4rem;align-self:flex-start}.message-user{background:var(--user-bubble);border-top-right-radius:.4rem;align-self:flex-end}.message-system{text-align:center;background:var(--system-bubble);align-self:center;max-width:min(92%,30rem)}.message-tone-correct{background:var(--correct-bubble)}.message-tone-incorrect{background:var(--incorrect-bubble)}.message-tone-error{border:1px solid #b8544333}.message-text{white-space:pre-wrap;word-break:break-word;margin:0}.message-time{text-align:right;color:var(--text-soft);margin-top:.35rem;font-size:.72rem;display:block}.chat-composer{padding:.9rem 1rem calc(.9rem + env(safe-area-inset-bottom));background:var(--composer-bg);border-top:1px solid var(--shell-border);-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);grid-template-columns:minmax(0,1fr) auto;gap:.75rem;display:grid}.chat-composer textarea{resize:none;border:1px solid var(--composer-border);min-width:0;min-height:3rem;max-height:6.4rem;font:inherit;color:var(--text-main);background:var(--composer-field);border-radius:1.25rem;padding:.85rem 1rem;line-height:1.4;overflow-y:hidden;box-shadow:inset 0 1px 2px #1834270f}.chat-composer textarea::placeholder{color:#7b8b80}.chat-composer textarea:focus{border-color:#5da171;outline:none;box-shadow:0 0 0 3px #5da1712e}.chat-composer button,.chat-error-state button{height:3rem;font:inherit;color:#f8fff8;background:linear-gradient(135deg, var(--send-start) 0%, var(--send-end) 100%);border:none;border-radius:999px;padding:0 1.15rem;font-weight:700;box-shadow:0 10px 24px #1d6f4338}.chat-composer button:disabled{cursor:not-allowed;opacity:.55;box-shadow:none}@media (width>=768px){.chat-app{padding:calc(1.5rem + env(safe-area-inset-top)) 1.5rem 1.5rem}.chat-shell{border:1px solid var(--shell-border);width:min(100%,860px);height:calc(100dvh - 3rem);box-shadow:var(--shadow-soft);border-radius:1.75rem;overflow:hidden}.chat-header{padding:1rem 1.25rem}.chat-thread{padding:1.25rem 1.4rem}.chat-composer{padding:1rem 1.25rem}}@media (width<=520px){.chat-header{padding:calc(.85rem + env(safe-area-inset-top)) .9rem .85rem}.chat-thread{padding:.9rem .75rem}.message{max-width:88%}.chat-composer{padding:.8rem .75rem calc(.8rem + env(safe-area-inset-bottom));gap:.6rem}.chat-composer button{padding:0 1rem}}