/* ══════════════════════════════════════════════════
   Sensei — Shared Design System
   Loaded before Server and UI app.css files.
   ══════════════════════════════════════════════════ */

/* ── Design Tokens ────────────────────────────── */

:root {
    --cs-accent:       #ea580c;
    --cs-accent-dark:  #c2410c;
    --cs-accent-light: #fff7ed;
    --cs-dark:         #1e293b;
    --cs-darker:       #0f172a;
    --cs-surface:      #f8fafc;
    --cs-border:       #e2e8f0;
    --cs-text:         #0f172a;
    --cs-text-muted:   #64748b;
    --cs-radius:       12px;
    --cs-radius-sm:    8px;
    --cs-tab-height:   64px;
    --cs-success:      #26b050;
    --cs-error:        #e50000;
    --cs-code-bg:      #1e1e1e;
    --cs-code-text:    #d4d4d4;
    --cs-inline-code-bg: rgba(0, 0, 0, 0.06);
}

/* ── Base Typography ──────────────────────────── */

html, body {
    font-family: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Helvetica, Arial, sans-serif;
    font-size: 15px;
    color: var(--cs-text);
    background: var(--cs-surface);
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, .brand-name {
    font-family: 'Syne', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    font-weight: 700;
    letter-spacing: -0.02em;
}

a, .btn-link { color: var(--cs-accent); }
a:hover { color: var(--cs-accent-dark); }

/* ── Buttons ──────────────────────────────────── */

.btn-primary {
    color: #fff;
    background-color: var(--cs-accent);
    border-color: var(--cs-accent);
    font-weight: 600;
    letter-spacing: 0.01em;
    border-radius: var(--cs-radius-sm);
    transition: background 0.15s, transform 0.1s;
}
.btn-primary:hover,
.btn-primary:active { background-color: var(--cs-accent-dark); border-color: var(--cs-accent-dark); }
.btn-primary:active { transform: scale(0.98); }

.btn:focus, .btn:active:focus, .btn-link.nav-link:focus, .form-control:focus, .form-check-input:focus {
    box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem var(--cs-accent);
    outline: none;
}

/* ── Forms ────────────────────────────────────── */

.form-control {
    border: 1.5px solid var(--cs-border);
    border-radius: var(--cs-radius-sm);
    padding: 0.75rem 0.85rem;
    font-size: 0.95rem;
    transition: border-color 0.15s, box-shadow 0.15s;
    background: var(--cs-surface);
}
.form-control:focus {
    border-color: var(--cs-accent);
    box-shadow: 0 0 0 3px rgba(234, 88, 12, 0.15);
}

.content { padding-top: 1.1rem; }
h1:focus { outline: none; }
.valid.modified:not([type=checkbox]) { outline: 1px solid var(--cs-success); }
.invalid { outline: 1px solid var(--cs-error); }
.validation-message { color: var(--cs-error); }

/* ── Blazor Error Handling ────────────────────── */

.blazor-error-boundary {
    background: url(data:image/svg+xml;base64,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) no-repeat 1rem/1.8rem, #b32121;
    padding: 1rem 1rem 1rem 3.7rem;
    color: white;
}

    .blazor-error-boundary::after {
        content: "An error has occurred."
    }

#blazor-error-ui {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 0.6rem 1.25rem 0.7rem 1.25rem;
    background: lightyellow;
    box-shadow: 0 -1px 2px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    color-scheme: light only;
}

    #blazor-error-ui .dismiss {
        cursor: pointer;
        position: absolute;
        right: 0.75rem;
        top: 0.5rem;
    }

.darker-border-checkbox.form-check-input {
    border-color: #929292;
}

.form-floating > .form-control-plaintext::placeholder, .form-floating > .form-control::placeholder {
    color: var(--bs-secondary-color);
    text-align: end;
}

.form-floating > .form-control-plaintext:focus::placeholder, .form-floating > .form-control:focus::placeholder {
    text-align: start;
}

/* ── Chat Components ──────────────────────────── */

.chat-window {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 400px;
    overflow: hidden;
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.chat-message {
    max-width: 75%;
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    word-wrap: break-word;
}

.user-message {
    align-self: flex-end;
    background-color: var(--cs-accent);
    color: #fff;
}

.assistant-message {
    align-self: flex-start;
    background-color: var(--cs-surface);
    color: var(--cs-text);
}

.message-role {
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
    opacity: 0.7;
}

.message-content {
    white-space: pre-wrap;
    line-height: 1.5;
}

.markdown-content { white-space: normal; }
.markdown-content p { margin: 0 0 0.5rem; }
.markdown-content p:last-child { margin-bottom: 0; }
.markdown-content code { background: var(--cs-inline-code-bg); padding: 0.15rem 0.35rem; border-radius: 3px; font-size: 0.9em; }
.markdown-content pre { background: var(--cs-code-bg); color: var(--cs-code-text); padding: 0.75rem 1rem; border-radius: 6px; overflow-x: auto; margin: 0.5rem 0; }
.markdown-content pre code { background: none; padding: 0; color: inherit; font-size: 0.85em; }
.markdown-content ul, .markdown-content ol { margin: 0.25rem 0; padding-left: 1.5rem; }
.markdown-content strong { font-weight: 600; }
.markdown-content blockquote { border-left: 3px solid var(--cs-accent); padding-left: 0.75rem; margin: 0.5rem 0; color: var(--cs-text-muted); }

/* ── Quiz Transition Card ────────────────────── */

.quiz-transition-card {
    align-self: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    padding: 1.25rem 2rem;
    margin: 1rem auto;
    max-width: 380px;
    background: linear-gradient(135deg, #e8fbe8 0%, #f0fff0 100%);
    border: 2px solid #58CC02;
    border-radius: 16px;
    box-shadow: 0 4px 16px rgba(88, 204, 2, 0.15);
    text-align: center;
    animation: quizTransitionIn 0.4s ease-out;
}

.quiz-transition-emoji {
    font-size: 2rem;
    line-height: 1;
}

.quiz-transition-text {
    margin: 0;
    font-family: 'Nunito', 'DM Sans', sans-serif;
    font-size: 0.95rem;
    font-weight: 700;
    color: #1a7a00;
    line-height: 1.4;
}

@keyframes quizTransitionIn {
    0% {
        opacity: 0;
        transform: scale(0.9) translateY(10px);
    }
    100% {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.typing-indicator { font-style: italic; opacity: 0.7; }

.chat-input {
    display: flex;
    gap: 0.5rem;
    padding: 0.75rem;
    padding-bottom: calc(0.75rem + env(safe-area-inset-bottom, 0px));
    border-top: 1px solid var(--cs-border);
    background: var(--cs-surface);
}

.chat-input textarea {
    flex: 1;
    resize: none;
    border: 1px solid var(--cs-border);
    border-radius: 0.5rem;
    padding: 0.5rem 0.75rem;
    font-size: 0.95rem;
    font-family: inherit;
    max-height: 40vh;
    overflow-y: auto;
}

.chat-input textarea:focus {
    outline: none;
    border-color: var(--cs-accent);
    box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem var(--cs-accent);
}

.chat-input button { align-self: flex-end; }

/* ── Session Page ─────────────────────────────── */

.session-page {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 24px 24px 0;
}

.session-header {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.session-page > .text-muted {
    margin-bottom: 1rem;
    margin-top: 0;
}

.session-header h2 { margin: 0; }

.phase-badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.phase-badge.socratic { background-color: var(--cs-accent-light); color: var(--cs-accent-dark); }
.phase-badge.quiz { background-color: #fff3cd; color: #856404; }
.phase-badge.completed { background-color: #d4edda; color: #155724; }

.grade-result { margin-bottom: 1rem; }

/* ── Track View ───────────────────────────────── */

.track-view { padding: 24px; }
.track-view .topic-card { transition: box-shadow 0.15s; }
.track-view .topic-card:hover { box-shadow: 0 0.25rem 0.5rem rgba(0,0,0,0.1); }
.lock-icon { opacity: 0.5; }
.track-view .topic-card.locked { background-color: var(--cs-surface); color: var(--cs-text-muted); }
.track-view .topic-card.locked h5 { color: var(--cs-text-muted); }
.topic-number { font-weight: 600; color: var(--cs-accent); font-size: 0.95rem; min-width: 1.5rem; }

/* ── Grade Badges ─────────────────────────────── */

.grade-badge { padding: 2px 8px; border-radius: 12px; font-size: 0.75rem; font-weight: 600; white-space: nowrap; }
.badge-mastered   { background: #ffd700; color: #333; }
.badge-solid      { background: #28a745; color: white; }
.badge-developing { background: #ffc107; color: #333; }
.badge-needswork  { background: #dc3545; color: white; }
.badge-ungraded   { background: #6c757d; color: white; }

/* ── Progress Bar ─────────────────────────────── */

.progress-bar-wrapper { width: 100%; }
.progress-bar-container { position: relative; background: var(--cs-border); border-radius: 8px; height: 8px; margin: 4px 0 2px; overflow: hidden; }
.progress-bar-fill { background: linear-gradient(90deg, var(--cs-accent), var(--cs-accent-dark)); border-radius: 8px; height: 100%; transition: width 0.3s ease; }
.progress-text { font-size: 0.75rem; color: var(--cs-text-muted); margin-top: 4px; display: block; white-space: nowrap; text-align: center; }

/* ── Progression Mode Selector ────────────────── */

.progression-mode { display: flex; align-items: center; gap: 0.5rem; margin-bottom: 0.5rem; }
.progression-mode label { font-weight: 600; margin-bottom: 0; }
.progression-mode select { padding: 0.25rem 0.5rem; border-radius: 0.375rem; border: 1px solid var(--cs-border); font-size: 0.9rem; }

/* ── Streak Banner ────────────────────────────── */

.streak-banner {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--cs-dark);
    color: white;
    border-radius: var(--cs-radius);
    margin-bottom: 1.5rem;
}

.streak-flame { display: flex; align-items: center; gap: 0.25rem; font-size: 2rem; }
.streak-flame.active .flame-icon { animation: pulse 1.5s ease-in-out infinite; }
.streak-flame.inactive { opacity: 0.5; filter: grayscale(1); }
.streak-count { font-size: 2.5rem; font-weight: 800; font-family: 'Syne', sans-serif; }
.streak-details { display: flex; flex-direction: column; }
.streak-label { font-size: 1.1rem; font-weight: 600; }
.streak-longest { font-size: 0.85rem; opacity: 0.7; }
.streak-banner.milestone { background: linear-gradient(135deg, #ff6b35, #ffd700); animation: celebrate 0.5s ease-out; }
.milestone-message { margin-left: auto; font-weight: 700; font-size: 1rem; animation: fadeInUp 0.5s ease-out; }

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

@keyframes celebrate {
    0% { transform: scale(0.95); }
    50% { transform: scale(1.02); }
    100% { transform: scale(1); }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ── Dashboard ────────────────────────────────── */

.dashboard { max-width: 800px; margin: 0 auto; }
.track-cards { display: grid; gap: 1rem; margin-bottom: 2rem; }
.track-card {
    padding: 1.5rem;
    background: var(--cs-surface);
    border-radius: var(--cs-radius);
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    border: 1px solid var(--cs-border);
}
.track-card:hover { transform: translateY(-2px); box-shadow: 0 4px 16px rgba(0,0,0,0.12); }
.recent-sessions { display: flex; flex-direction: column; gap: 0.5rem; }
.recent-session-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.75rem 1rem;
    background: var(--cs-surface);
    border-radius: var(--cs-radius-sm);
    cursor: pointer;
    border: 1px solid var(--cs-border);
    transition: background 0.15s;
}
.recent-session-item:hover { background: var(--cs-accent-light); }
.session-topic { flex: 1; font-weight: 500; }
.session-date { font-size: 0.85rem; color: var(--cs-text-muted); }

/* ── Loading State ────────────────────────────── */

.loading-state {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 48px 24px;
    color: var(--cs-text-muted);
    font-size: 0.95rem;
}

/* ── Empty State ──────────────────────────────── */

.empty-state { text-align: center; padding: 48px 24px; }
.empty-state-icon { font-size: 3rem; margin-bottom: 12px; }
.empty-state-text { color: var(--cs-text-muted); margin-bottom: 20px; }

/* ── Track Card Grid ──────────────────────────── */

.track-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.track-card {
    display: flex;
    background: var(--cs-surface);
    border-radius: var(--cs-radius-sm);
    overflow: hidden;
    cursor: pointer;
    transition: transform 0.15s, box-shadow 0.15s;
    border: 1px solid var(--cs-border);
}

.track-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.track-card--locked {
    opacity: 0.7;
}

.track-card--locked:hover {
    opacity: 0.85;
}

.track-card__accent {
    width: 4px;
    flex-shrink: 0;
}

.track-card__body {
    padding: 1rem;
    flex: 1;
}

.track-card__header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.track-card__lock {
    font-size: 0.875rem;
}

.track-card__name {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
}

.track-card__description {
    font-size: 0.85rem;
    color: var(--cs-text-muted);
    margin: 0.5rem 0;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.track-card__cta {
    font-size: 0.85rem;
    color: var(--cs-accent);
    font-weight: 600;
}

.track-card__cta--soon {
    color: var(--cs-text-muted);
    font-weight: 400;
}

.track-card__progress {
    font-size: 0.8rem;
    color: var(--cs-text-muted);
}

/* ══════════════════════════════════════════════════
   Dark Mode (system-aware)
   ══════════════════════════════════════════════════ */

@media (prefers-color-scheme: dark) {
    :root {
        --cs-surface: #1e293b;
        --cs-border:  #334155;
        --cs-text:    #f1f5f9;
        --cs-text-muted: #94a3b8;
        --cs-accent-light: #431407;
        --cs-success:      #4ade80;
        --cs-error:        #f87171;
        --cs-inline-code-bg: rgba(255, 255, 255, 0.1);
    }

    html, body { background: var(--cs-darker); color: var(--cs-text); }

    /* Forms */
    .form-control { background: var(--cs-darker); color: var(--cs-text); border-color: var(--cs-border); }

    /* Chat */
    .chat-window { background: var(--cs-darker); }
    .chat-input  { background: var(--cs-surface); border-color: var(--cs-border); }
    .chat-input textarea {
        background: var(--cs-darker);
        color: var(--cs-text);
        border-color: var(--cs-border);
    }
    .chat-input textarea:focus {
        box-shadow: 0 0 0 0.1rem var(--cs-darker), 0 0 0 0.25rem var(--cs-accent);
    }
    .chat-message.assistant-message { background: var(--cs-surface); }

    /* Quiz transition card */
    .quiz-transition-card {
        background: linear-gradient(135deg, rgba(88,204,2,0.15) 0%, rgba(88,204,2,0.08) 100%);
        border-color: #58CC02;
        box-shadow: 0 4px 16px rgba(88, 204, 2, 0.1);
    }
    .quiz-transition-text { color: #7ddf64; }

    /* Phase badges */
    .phase-badge.socratic { background: rgba(234,88,12,0.15); color: var(--cs-accent); }
    .phase-badge.quiz { background: rgba(234,179,8,0.15); color: #fbbf24; }
    .phase-badge.completed { background: rgba(34,197,94,0.15); color: #4ade80; }

    /* Grade badges */
    .badge-mastered { color: #1a1a1a; }
    .badge-developing { color: #1a1a1a; }

    /* Cards and surfaces */
    .track-card,
    .recent-session-item { background: var(--cs-surface); }

    /* Inputs */
    input, select, textarea {
        background: var(--cs-surface);
        color: var(--cs-text);
        border-color: var(--cs-border);
    }

    /* Modals */
    .modal-content { background: var(--cs-surface); color: var(--cs-text); }

    /* Focus ring */
    .btn:focus, .btn:active:focus, .btn-link.nav-link:focus, .form-control:focus, .form-check-input:focus {
        box-shadow: 0 0 0 0.1rem var(--cs-darker), 0 0 0 0.25rem var(--cs-accent);
    }

    /* Shadows */
    .track-card:hover { box-shadow: 0 4px 16px rgba(0,0,0,0.3); }
}

/* ══════════════════════════════════════════════════
   Reduced Motion
   ══════════════════════════════════════════════════ */

@media (prefers-reduced-motion: reduce) {
    .streak-flame.active .flame-icon,
    .milestone-message,
    .grade-card,
    .streak-banner.milestone,
    .quiz-transition-card {
        animation: none !important;
    }

    .track-card,
    .btn-primary,
    .progress-bar-fill {
        transition: none !important;
    }
}