.ai-tutor-widget {
    --tutor-surface: #ffffff;
    --tutor-transcript: #f5f9f2;
    --tutor-ink: #1a1230;
    --tutor-muted: #665f78;
    --tutor-border: #e5e0f3;
    --tutor-accent: #16a34a;
    --tutor-accent-strong: #0f766e;
    --tutor-accent-soft: #dcfce7;
    position: fixed;
    right: 20px;
    bottom: 20px;
    z-index: 1200;
    display: flex;
    flex-direction: column;
    width: min(400px, calc(100vw - 32px));
    max-height: min(650px, calc(100dvh - 40px));
    overflow: hidden;
    color: var(--tutor-ink);
    background: linear-gradient(180deg, rgba(255,255,255,0.98), rgba(245,249,242,0.98));
    border: 1px solid rgba(132, 111, 180, 0.18);
    border-radius: 22px;
    box-shadow: 0 25px 65px rgba(18, 66, 36, 0.16), 0 12px 30px rgba(79, 70, 229, 0.1);
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    transform: translateY(0);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.ai-tutor-widget::before {
    content: "";
    position: absolute;
    inset: 0 auto auto 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, #4f46e5 0%, #7c3aed 30%, #22c55e 75%, #16a34a 100%);
}

.ai-tutor-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 13px 14px;
    color: #fff;
    background: linear-gradient(125deg, #0f766e 0%, #16a34a 28%, #4f46e5 62%, #7c3aed 100%);
    border-bottom: 1px solid rgba(255,255,255,0.14);
}
.ai-tutor-header-title { display: flex; align-items: center; min-width: 0; gap: 10px; }
.ai-tutor-header-badge {
    display: inline-grid;
    flex: 0 0 34px;
    width: 34px;
    height: 34px;
    place-items: center;
    background: rgba(255,255,255,.18);
    border: 1px solid rgba(255,255,255,.28);
    border-radius: 11px;
    box-shadow: inset 0 1px 8px rgba(255,255,255,0.12);
}
.ai-tutor-heading { display: block; font-size: 16px; line-height: 1.15; }
.ai-tutor-status { display: flex; align-items: center; gap: 5px; margin-top: 3px; color: rgba(255,255,255,.9); font-size: 12px; font-weight: 600; }
.ai-tutor-status-dot { width: 8px; height: 8px; background: #6ee7b7; border: 2px solid rgba(255,255,255,.65); border-radius: 50%; }
.ai-tutor-close { display: grid; flex: 0 0 44px; width: 44px; height: 44px; place-items: center; padding: 0; color: #fff; background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.14); border-radius: 12px; cursor: pointer; font-size: 20px; transition: background 0.15s ease, transform 0.15s ease; }
.ai-tutor-close:hover { background: rgba(255,255,255,.16); transform: translateY(-1px); }

.ai-tutor-body {
    flex: 1 1 auto;
    min-height: 160px;
    overflow-y: auto;
    padding: 16px 14px 12px;
    background:
        radial-gradient(circle at top left, rgba(34,197,94,0.08), transparent 30%),
        radial-gradient(circle at bottom right, rgba(79,70,229,0.08), transparent 30%),
        var(--tutor-transcript);
    scrollbar-color: #b9b3d1 transparent;
}
.ai-tutor-message {
    max-width: 91%;
    margin: 0 0 14px;
    padding: 11px 12px;
    border-radius: 16px;
    font-size: 15px;
    line-height: 1.55;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
}
.ai-tutor-message.bot {
    background: rgba(255,255,255,0.96);
    border: 1px solid rgba(139, 92, 246, 0.12);
    border-top-left-radius: 5px;
    box-shadow: 0 10px 24px rgba(91, 53, 183, 0.06);
}
.ai-tutor-message.user {
    margin-left: auto;
    color: #fff;
    background: linear-gradient(135deg, #0f766e 0%, #16a34a 35%, #22c55e 100%);
    border-top-right-radius: 5px;
    box-shadow: 0 12px 26px rgba(34,197,94,0.18);
}
.ai-tutor-message.error { color: #991b1b; background: #fff1f2; border: 1px solid #fecdd3; }
.ai-tutor-retry { min-height: 36px; margin-top: 10px; padding: 7px 10px; color: #991b1b; background: #fff; border: 1px solid #fda4af; border-radius: 8px; cursor: pointer; font: inherit; font-size: 13px; font-weight: 700; }
.ai-tutor-retry:hover { background: #fff7f8; }
.ai-tutor-message-meta { display: flex; align-items: center; gap: 6px; margin-bottom: 5px; color: var(--tutor-muted); font-size: 11px; font-weight: 700; letter-spacing: .015em; }
.user .ai-tutor-message-meta { color: rgba(255,255,255,.82); justify-content: flex-end; }
.ai-tutor-marker { display: inline-grid; width: 16px; height: 16px; place-items: center; color: #fff; background: linear-gradient(135deg, #4f46e5, #7c3aed); border-radius: 5px; font-size: 9px; }
.ai-tutor-time { font-weight: 500; }
.ai-tutor-thinking { display: inline-flex; align-items: center; gap: 7px; color: var(--tutor-muted); }
.ai-tutor-thinking-dots { display: inline-flex; gap: 3px; }
.ai-tutor-thinking-dots i { width: 5px; height: 5px; background: #7c3aed; border-radius: 50%; animation: tutor-pulse 1.1s infinite ease-in-out; }
.ai-tutor-thinking-dots i:nth-child(2) { animation-delay: .13s; }
.ai-tutor-thinking-dots i:nth-child(3) { animation-delay: .26s; }

.ai-tutor-section {
    margin: 2px 0 16px;
    padding: 12px;
    background: rgba(255,255,255,.72);
    border: 1px solid var(--tutor-border);
    border-radius: 12px;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.5);
}
.ai-tutor-section-heading { display: flex; align-items: center; gap: 7px; margin: 0 0 9px; color: var(--tutor-muted); font-size: 11px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.ai-tutor-section-heading i { color: #16a34a; }
.ai-tutor-related { display: grid; gap: 7px; }
.ai-tutor-related-item, .ai-tutor-chip {
    width: 100%;
    min-height: 42px;
    padding: 9px 10px;
    color: var(--tutor-ink);
    background: linear-gradient(180deg, rgba(255,255,255,0.9), rgba(247,250,255,0.9));
    border: 1px solid var(--tutor-border);
    border-radius: 10px;
    cursor: pointer;
    font: inherit;
    font-size: 13px;
    font-weight: 600;
    line-height: 1.3;
    text-align: left;
    transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}
.ai-tutor-related-item:hover, .ai-tutor-chip:hover {
    border-color: rgba(34,197,94,0.45);
    transform: translateY(-1px);
    box-shadow: 0 10px 18px rgba(34,197,94,0.08);
}
.ai-tutor-suggestions { display: flex; flex-wrap: wrap; gap: 7px; }
.ai-tutor-chip {
    flex: 1 1 140px;
    width: auto;
    color: #1f2d18;
    background: linear-gradient(180deg, #f0fdf4, #ecfeff);
    border-color: rgba(22,163,74,0.18);
}

.ai-tutor-form {
    display: flex;
    flex: 0 0 auto;
    gap: 8px;
    padding: 12px 14px 14px;
    background: linear-gradient(180deg, rgba(255,255,255,0.96), rgba(248,250,252,0.96));
    border-top: 1px solid var(--tutor-border);
}
.ai-tutor-input {
    min-width: 0;
    flex: 1;
    min-height: 44px;
    padding: 10px 12px;
    color: var(--tutor-ink);
    background: rgba(255,255,255,0.94);
    border: 1px solid #d8d0eb;
    border-radius: 12px;
    font: inherit;
    font-size: 15px;
    box-shadow: inset 0 1px 2px rgba(15, 23, 42, 0.04);
}
.ai-tutor-input::placeholder { color: #796f8c; }
.ai-tutor-input:focus-visible, .ai-tutor-close:focus-visible, .ai-tutor-send:focus-visible, .ai-tutor-chip:focus-visible, .ai-tutor-related-item:focus-visible, .ai-tutor-fab:focus-visible {
    outline: 3px solid rgba(34,197,94,.55);
    outline-offset: 2px;
}
.ai-tutor-send {
    display: grid;
    flex: 0 0 44px;
    width: 44px;
    height: 44px;
    place-items: center;
    padding: 0;
    color: #fff;
    background: linear-gradient(135deg, #16a34a 0%, #22c55e 100%);
    border: 0;
    border-radius: 12px;
    cursor: pointer;
    font-size: 16px;
    box-shadow: 0 12px 24px rgba(34,197,94,0.26);
}
.ai-tutor-send:hover:not(:disabled) { background: linear-gradient(135deg, #15803d, #16a34a); }
.ai-tutor-send:disabled { cursor: wait; opacity: .62; }
.ai-tutor-fab {
    position: fixed;
    right: 20px;
    bottom: 20px;
    z-index: 1100;
    display: grid;
    width: 62px;
    height: 62px;
    place-items: center;
    color: #fff;
    background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 40%, #16a34a 100%);
    border: 2px solid rgba(255,255,255,.8);
    border-radius: 50%;
    box-shadow: 0 18px 38px rgba(91, 53, 183, .38);
    cursor: pointer;
    font-size: 22px;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.ai-tutor-fab:hover { transform: translateY(-2px); box-shadow: 0 22px 42px rgba(91, 53, 183, .42); }
.ai-tutor-fab::after { position: absolute; top: 3px; right: 4px; width: 10px; height: 10px; content: ''; background: #6ee7b7; border: 2px solid #fff; border-radius: 50%; }
.tutorial-card.ai-tutor-highlight { box-shadow: 0 0 0 3px rgba(34,197,94,.5), 0 18px 30px rgba(16,185,129,.18); border: 2px solid rgba(34,197,94,.7); transform: translateY(-2px); transition: box-shadow .2s ease, transform .2s ease; }
.ai-tutor-hidden { display: none !important; }
body.dark-mode .ai-tutor-widget { --tutor-surface: #151a2b; --tutor-transcript: #0e1423; --tutor-ink: #f4f1ff; --tutor-muted: #c5bdd6; --tutor-border: #39334f; box-shadow: 0 24px 60px rgba(0,0,0,.48); }
body.dark-mode .ai-tutor-input { border-color: #514968; }
body.dark-mode .ai-tutor-related-item, body.dark-mode .ai-tutor-chip { background: #1c2134; }
body.dark-mode .ai-tutor-related-item:hover, body.dark-mode .ai-tutor-chip:hover { background: #27223b; }
body.dark-mode .ai-tutor-message.error { color: #fecaca; background: #461d29; border-color: #9f1239; }
body.dark-mode .ai-tutor-retry { color: #fecaca; background: #281725; border-color: #be123c; }
body.dark-mode .ai-tutor-retry:hover { background: #3b1c2c; }
@keyframes tutor-pulse { 0%, 80%, 100% { opacity: .35; transform: translateY(0); } 40% { opacity: 1; transform: translateY(-3px); } }
@media (max-width: 520px) { .ai-tutor-widget { top: max(8px, env(safe-area-inset-top)); right: 8px; bottom: max(8px, env(safe-area-inset-bottom)); left: 8px; width: auto; max-height: none; border-radius: 15px; } .ai-tutor-fab { right: 14px; bottom: 14px; width: 58px; height: 58px; } .ai-tutor-message { max-width: 95%; } .ai-tutor-body { min-height: 0; padding: 14px 12px 10px; } }
@media (prefers-reduced-motion: reduce) { .ai-tutor-thinking-dots i { animation: none; } .ai-tutor-fab { transition: none; } }