/* Self-hosted so the app keeps its typography offline (PWA). */
@font-face {
    font-family: 'Outfit';
    font-style: normal;
    font-weight: 300 700;
    font-display: swap;
    src: url('assets/outfit-latin-ext.woff2') format('woff2');
    unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF,
                   U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF,
                   U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
    font-family: 'Outfit';
    font-style: normal;
    font-weight: 300 700;
    font-display: swap;
    src: url('assets/outfit-latin.woff2') format('woff2');
    unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA,
                   U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122,
                   U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

:root {
    /* Lets the browser render native widgets - the <select> popup, scrollbars,
       checkboxes - in dark mode. Without it Firefox paints its light system
       highlight behind the hovered option while keeping our near-white text,
       so the selected row becomes unreadable. Styling `option` colours by hand
       does not fix that reliably; this does, in every engine. */
    color-scheme: dark;

    --bg-dark: #121214;
    --text-light: #f5f5f7;
    --text-muted: #a1a1aa;
    --primary-red: #e11d48;
    --primary-red-hover: #be123c;
    --glass-bg: rgba(30, 30, 35, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --success: #10b981;
    --error: #ef4444;
    --partial: #f59e0b;
    --info: #38bdf8;
    --font: 'Outfit', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html { -webkit-text-size-adjust: 100%; }

body {
    font-family: var(--font);
    background-color: var(--bg-dark);
    color: var(--text-light);
    min-height: 100vh;
    min-height: 100dvh;
    overflow-x: hidden;
    position: relative;
    line-height: 1.45;
}

/* Background ------------------------------------------------------------- */

.background-animation {
    position: fixed;
    inset: 0;
    z-index: -1;
    overflow: hidden;
    background: #0f0f11;
}

.blob {
    position: absolute;
    border-radius: 50%;
    /* 100px on a 50vw element is a heavy per-frame repaint on phones. */
    filter: blur(70px);
    opacity: 0.4;
    will-change: transform;
    animation: float 24s infinite ease-in-out alternate;
}

.blob.red {
    background: linear-gradient(to right, #9f1239, #e11d48);
    width: 46vw; height: 46vw;
    min-width: 320px; min-height: 320px;
    top: -10%; right: -10%;
}

.blob.white {
    background: rgba(255, 255, 255, 0.1);
    width: 38vw; height: 38vw;
    min-width: 260px; min-height: 260px;
    bottom: -10%; left: -10%;
    animation-delay: -8s;
}

@keyframes float {
    0%   { transform: translate(0, 0) scale(1); }
    100% { transform: translate(-40px, 40px) scale(1.15); }
}

/* Layout ----------------------------------------------------------------- */

.container {
    width: 100%;
    max-width: 820px;
    /* margin auto instead of flex-centering the body: a panel taller than the
       viewport used to have its top clipped and unreachable. */
    margin: 0 auto;
    padding: 2rem 1.25rem calc(2rem + env(safe-area-inset-bottom));
    position: relative;
    z-index: 1;
}

.screen { display: none; animation: fadeIn 0.35s ease-out both; }
.screen.active { display: block; }

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

header { text-align: center; margin-bottom: 1.75rem; }

h1 {
    font-size: clamp(2.2rem, 8vw, 3rem);
    font-weight: 700;
    line-height: 1.1;
    background: linear-gradient(to right, #fff, #a1a1aa);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.35rem;
}

/* An inline SVG rather than the flag emoji: Windows has no flag glyphs (it would
   render as the letters "PL"), and the h1 gradient clip paints emoji grey. */
h1 .flag {
    height: 0.62em;
    width: auto;
    margin-left: 0.28em;
    vertical-align: 0.06em;
    border-radius: 3px;
    filter: drop-shadow(0 2px 6px rgba(0, 0, 0, 0.45));
}

header p { color: var(--text-muted); }

h2 { font-size: 1.4rem; margin-bottom: 1.25rem; font-weight: 600; }

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: clamp(1.25rem, 4vw, 2.25rem);
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    margin-bottom: 1.25rem;
}

.muted { color: var(--text-muted); }
.hidden { display: none !important; }

/* Dashboard -------------------------------------------------------------- */

.dashboard-panel { padding: 0; overflow: hidden; }

.dash-summary {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    padding: 1.1rem clamp(1.25rem, 4vw, 2.25rem);
    list-style: none;
    user-select: none;
    transition: background 0.15s;
}

.dash-summary::-webkit-details-marker { display: none; }
.dash-summary:hover { background: rgba(255, 255, 255, 0.04); }

/* Chevron drawn in CSS so it can rotate on open without an extra element. */
.dash-summary::after {
    content: '';
    width: 8px;
    height: 8px;
    margin-left: 0.15rem;
    border-right: 2px solid var(--text-muted);
    border-bottom: 2px solid var(--text-muted);
    transform: rotate(45deg) translate(-2px, -2px);
    transition: transform 0.2s;
}

#dashboard[open] .dash-summary::after { transform: rotate(-135deg) translate(-2px, -2px); }

.dash-summary-title { font-weight: 600; font-size: 1.05rem; }

.dash-summary-value {
    margin-left: auto;
    font-size: 0.84rem;
    color: var(--text-muted);
    text-align: right;
}

.dash-summary-value.has-due { color: #fda4af; }

.dash-body {
    padding: 0 clamp(1.25rem, 4vw, 2.25rem) clamp(1.25rem, 4vw, 2.25rem);
    border-top: 1px solid var(--glass-border);
    padding-top: 1.5rem;
}

.dash-footer { text-align: center; margin-top: 1.25rem; }

.dash-main {
    display: flex;
    align-items: center;
    gap: 1.75rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.ring-wrap { position: relative; width: 132px; height: 132px; flex-shrink: 0; }

.ring { width: 100%; height: 100%; transform: rotate(-90deg); }

.ring-track, .ring-fill {
    fill: none;
    stroke-width: 9;
    stroke-linecap: round;
}

.ring-track { stroke: rgba(255, 255, 255, 0.08); }

.ring-fill {
    stroke: var(--primary-red);
    transition: stroke-dashoffset 0.8s cubic-bezier(0.22, 1, 0.36, 1);
    filter: drop-shadow(0 0 6px rgba(225, 29, 72, 0.5));
}

.ring-label {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.ring-label strong { font-size: 1.9rem; font-weight: 700; line-height: 1; }
.ring-label small { color: var(--text-muted); font-size: 0.72rem; margin-top: 0.2rem; }

.dash-stats {
    flex: 1;
    min-width: 240px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.6rem;
}

.stat-tile {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--glass-border);
    border-radius: 14px;
    padding: 0.7rem 0.85rem;
    display: flex;
    flex-direction: column;
    gap: 0.1rem;
}

.stat-value { font-size: 1.5rem; font-weight: 700; line-height: 1.1; }
.stat-name { font-size: 0.72rem; color: var(--text-muted); }

.pill {
    display: inline-block;
    min-width: 1.6rem;
    padding: 0.1rem 0.5rem;
    margin-left: 0.4rem;
    border-radius: 999px;
    background: rgba(0, 0, 0, 0.28);
    font-size: 0.85rem;
}

.cat-progress-list { display: grid; gap: 0.7rem; margin-top: 1.25rem; }

.cat-progress-head {
    display: flex;
    justify-content: space-between;
    font-size: 0.82rem;
    margin-bottom: 0.3rem;
}

.cat-progress-track {
    position: relative;
    height: 6px;
    border-radius: 6px;
    background: rgba(255, 255, 255, 0.08);
    overflow: hidden;
}

.cat-progress-seen,
.cat-progress-mastered {
    position: absolute;
    inset: 0 auto 0 0;
    border-radius: 6px;
    transition: width 0.5s ease;
}

.cat-progress-seen { background: rgba(56, 189, 248, 0.35); }
.cat-progress-mastered { background: var(--success); }

/* Forms ------------------------------------------------------------------ */

.form-group { margin-bottom: 1.25rem; }

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
    gap: 1rem;
}

label { display: block; margin-bottom: 0.45rem; color: var(--text-muted); font-size: 0.9rem; }

.label-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 1rem;
}

.label-row label { margin-bottom: 0.45rem; }

.mini-actions { display: flex; gap: 0.75rem; }

.link-btn {
    background: none;
    border: none;
    color: var(--info);
    font-size: 0.82rem;
    font-weight: 600;
    padding: 0;
    width: auto;
    cursor: pointer;
    text-decoration: underline;
    text-underline-offset: 3px;
}

.link-btn:hover { color: #7dd3fc; }
.link-btn.danger { color: var(--text-muted); }
.link-btn.danger:hover { color: var(--error); }

select, input[type="search"] {
    width: 100%;
    background: rgba(0, 0, 0, 0.25);
    border: 1px solid var(--glass-border);
    color: white;
    padding: 0.85rem 1rem;
    border-radius: 12px;
    font-size: 1rem;
    font-family: var(--font);
    outline: none;
    transition: border-color 0.2s;
}

select:focus, input[type="search"]:focus { border-color: var(--primary-red); }

/* No `option` colours on purpose. The dropdown popup is drawn by the OS, and any
   author colour we set is applied to the resting rows but not to the row the
   browser highlights - which is exactly how the text ended up washed out in
   Firefox. `color-scheme: dark` on :root gives the popup a dark palette with a
   highlight the browser guarantees to be contrasting. */

.mode-hint {
    color: var(--text-muted);
    font-size: 0.84rem;
    margin: -0.4rem 0 1.1rem;
    min-height: 1.2em;
}

/* Checkboxes / toggles --------------------------------------------------- */

.checkbox-group {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
    gap: 0.4rem;
}

.checkbox-label, .switch-label {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    cursor: pointer;
    font-size: 0.92rem;
    padding: 0.5rem 0.65rem;
    border-radius: 10px;
    transition: background 0.15s;
    margin: 0;
    color: var(--text-light);
}

.checkbox-label:hover, .switch-label:hover { background: rgba(255, 255, 255, 0.05); }

.checkbox-label input, .switch-label input {
    accent-color: var(--primary-red);
    width: 1.05rem;
    height: 1.05rem;
    flex-shrink: 0;
}

.cat-count {
    margin-left: auto;
    font-size: 0.75rem;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.06);
    padding: 0.05rem 0.45rem;
    border-radius: 999px;
}

.toggle-group { display: grid; gap: 0.1rem; margin-bottom: 1.4rem; }

.switch-label.inline { padding: 0; font-size: 0.82rem; color: var(--text-muted); }

.is-disabled { opacity: 0.4; pointer-events: none; }

/* Buttons ---------------------------------------------------------------- */

button {
    cursor: pointer;
    border: none;
    font-weight: 600;
    font-size: 1rem;
    font-family: var(--font);
    border-radius: 12px;
    padding: 0.9rem 1.5rem;
    transition: transform 0.15s, background 0.2s, border-color 0.2s;
    width: 100%;
    color: white;
}

button:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible,
summary:focus-visible {
    outline: 2px solid var(--info);
    outline-offset: 2px;
}

.primary-btn {
    background: var(--primary-red);
    box-shadow: 0 4px 14px rgba(225, 29, 72, 0.35);
}

.primary-btn:hover:not(:disabled) { background: var(--primary-red-hover); transform: translateY(-2px); }
.primary-btn:disabled { opacity: 0.45; cursor: not-allowed; box-shadow: none; }

.secondary-btn {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--glass-border);
}

.secondary-btn:hover { background: rgba(255, 255, 255, 0.14); }

.big-btn { padding: 1.05rem 1.5rem; margin-bottom: 0.75rem; }

.icon-btn {
    width: 38px;
    height: 38px;
    padding: 0;
    flex-shrink: 0;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.07);
    border: 1px solid var(--glass-border);
    font-size: 1rem;
    line-height: 1;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.icon-btn:hover { background: rgba(255, 255, 255, 0.14); }

kbd {
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
    font-size: 0.7rem;
    padding: 0.1rem 0.35rem;
    border-radius: 5px;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.14);
    color: var(--text-muted);
    margin-left: 0.35rem;
    vertical-align: middle;
}

.footnote {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.8rem;
    padding-bottom: 1rem;
}

/* Deliberately as quiet as the question count next to it. */
.footnote a {
    color: inherit;
    text-decoration: underline;
    text-underline-offset: 3px;
    text-decoration-color: rgba(255, 255, 255, 0.25);
}

.footnote a:hover { color: var(--info); }
.footnote-sep { opacity: 0.5; margin: 0 0.15rem; }

/* Quiz screen ------------------------------------------------------------ */

.progress-container { margin-bottom: 1.5rem; }

.progress-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
    font-size: 0.88rem;
    color: var(--text-muted);
}

#question-counter { flex: 1; }

.badge {
    background: rgba(225, 29, 72, 0.2);
    color: #fda4af;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.78rem;
    border: 1px solid rgba(225, 29, 72, 0.3);
    white-space: nowrap;
}

.badge.small { font-size: 0.7rem; padding: 0.1rem 0.55rem; }

.progress-bar {
    height: 6px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    overflow: hidden;
}

#progress-fill {
    height: 100%;
    width: 0%;
    background: var(--primary-red);
    transition: width 0.4s ease, background 0.5s ease;
}

.sprint-bar {
    position: relative;
    height: 26px;
    margin-top: 0.6rem;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.07);
    overflow: hidden;
    display: flex;
    align-items: center;
}

#sprint-fill {
    position: absolute;
    inset: 0 auto 0 0;
    background: linear-gradient(90deg, #f59e0b, #e11d48);
    transition: width 0.12s linear;
}

#sprint-time {
    position: relative;
    margin-left: auto;
    margin-right: 0.7rem;
    font-size: 0.8rem;
    font-weight: 700;
    font-variant-numeric: tabular-nums;
}

.sprint-bar.critical #sprint-fill { animation: flash 0.6s infinite; }
.sprint-bar.penalty { outline: 2px solid var(--error); }

@keyframes flash { 0%, 100% { opacity: 1; } 50% { opacity: 0.45; } }

.question-head { display: flex; align-items: flex-start; gap: 0.85rem; }

#question-text {
    font-size: clamp(1.25rem, 4.2vw, 1.7rem);
    line-height: 1.35;
    margin-bottom: 1.75rem;
    flex: 1;
}

.input-area { margin-top: 0.5rem; }

.question-panel.shake { animation: shake 0.42s cubic-bezier(0.36, 0.07, 0.19, 0.97); }

@keyframes shake {
    10%, 90% { transform: translateX(-2px); }
    20%, 80% { transform: translateX(4px); }
    30%, 50%, 70% { transform: translateX(-7px); }
    40%, 60% { transform: translateX(7px); }
}

/* Quiz options ----------------------------------------------------------- */

.quiz-options { display: grid; gap: 0.65rem; }

.quiz-option {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    text-align: left;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    padding: 0.9rem 1rem;
    font-weight: 400;
    font-size: 0.98rem;
    line-height: 1.35;
}

.quiz-option:hover:not(:disabled) { background: rgba(255, 255, 255, 0.11); border-color: rgba(255, 255, 255, 0.2); }
.quiz-option:disabled { cursor: default; opacity: 0.75; }

.quiz-key {
    flex-shrink: 0;
    width: 26px; height: 26px;
    border-radius: 7px;
    background: rgba(0, 0, 0, 0.3);
    display: grid;
    place-items: center;
    font-size: 0.78rem;
    font-weight: 700;
    color: var(--text-muted);
}

.quiz-option.is-correct {
    background: rgba(16, 185, 129, 0.18);
    border-color: var(--success);
    opacity: 1;
}

.quiz-option.is-wrong {
    background: rgba(239, 68, 68, 0.18);
    border-color: var(--error);
    opacity: 1;
}

/* Swipe ------------------------------------------------------------------ */

.swipe-card {
    position: relative;
    min-height: 190px;
    display: grid;
    place-items: center;
    padding: 1.75rem 1.5rem;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--glass-border);
    text-align: center;
    cursor: grab;
    touch-action: none;
    user-select: none;
    transition: transform 0.25s ease, opacity 0.25s ease, border-color 0.2s;
}

.swipe-card:active { cursor: grabbing; }
.swipe-card.revealed { background: rgba(16, 185, 129, 0.08); border-color: rgba(16, 185, 129, 0.3); }
.swipe-card.tilt-right { border-color: var(--success); }
.swipe-card.tilt-left { border-color: var(--error); }

.swipe-face { font-size: 1.1rem; line-height: 1.5; }

.swipe-hint-tag {
    position: absolute;
    top: 1rem;
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    padding: 0.25rem 0.6rem;
    border-radius: 6px;
    opacity: 0;
    transition: opacity 0.15s;
}

.swipe-hint-tag.left { left: 1rem; color: var(--error); border: 2px solid var(--error); transform: rotate(-12deg); }
.swipe-hint-tag.right { right: 1rem; color: var(--success); border: 2px solid var(--success); transform: rotate(12deg); }

.swipe-card.tilt-left .swipe-hint-tag.left { opacity: 1; }
.swipe-card.tilt-right .swipe-hint-tag.right { opacity: 1; }

.swipe-card.gone-left { transform: translateX(-140%) rotate(-24deg); opacity: 0; }
.swipe-card.gone-right { transform: translateX(140%) rotate(24deg); opacity: 0; }

.swipe-help { margin-top: 0.9rem; font-size: 0.8rem; color: var(--text-muted); text-align: center; }

/* Feedback --------------------------------------------------------------- */

.feedback-panel {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--glass-border);
    animation: fadeIn 0.3s ease;
}

#feedback-title { font-size: 1rem; color: var(--text-muted); margin-bottom: 0.6rem; font-weight: 600; }

#correct-answer-text {
    font-size: 1.15rem;
    line-height: 1.55;
    margin-bottom: 1.25rem;
    color: #e2e8f0;
}

.feedback-success { color: var(--success) !important; }
.feedback-error { color: var(--error) !important; }

.grade-controls { text-align: center; margin-bottom: 1.25rem; }
.grade-controls p { margin-bottom: 0.85rem; color: var(--text-muted); font-size: 0.9rem; }

.btn-group { display: flex; gap: 0.7rem; }

.grade-btn {
    flex: 1;
    padding: 0.8rem 0.5rem;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    font-size: 0.88rem;
}

.grade-btn.error:hover   { background: rgba(239, 68, 68, 0.2); border-color: var(--error); }
.grade-btn.partial:hover { background: rgba(245, 158, 11, 0.2); border-color: var(--partial); }
.grade-btn.success:hover { background: rgba(16, 185, 129, 0.2); border-color: var(--success); }

/* Result ----------------------------------------------------------------- */

#result-screen { position: relative; }

.confetti-canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 5;
}

.result-panel { text-align: center; }

.score-circle {
    width: 148px; height: 148px;
    border-radius: 50%;
    border: 8px solid var(--primary-red);
    display: grid;
    place-items: center;
    margin: 0 auto 1.25rem;
    font-size: 2.4rem;
    font-weight: 700;
    transition: border-color 0.4s;
}

.result-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.6rem;
    margin-top: 1.5rem;
}

.result-stat {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 0.75rem 0.5rem;
    display: flex;
    flex-direction: column;
}

.result-stat strong { font-size: 1.35rem; }
.result-stat span { font-size: 0.72rem; color: var(--text-muted); }

.mistakes-container {
    margin-top: 1.75rem;
    text-align: left;
    background: rgba(0, 0, 0, 0.22);
    padding: 1.25rem;
    border-radius: 14px;
    max-height: 320px;
    overflow-y: auto;
}

.mistakes-container h3 { margin-bottom: 0.9rem; font-size: 1.05rem; }
.mistakes-container ul { list-style: none; }

.mistakes-container li {
    margin-bottom: 0.9rem;
    padding-bottom: 0.9rem;
    border-bottom: 1px solid var(--glass-border);
    font-size: 0.92rem;
}

.mistakes-container li strong { display: block; margin-bottom: 0.25rem; }
.mistakes-container li:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }

.action-buttons { display: flex; gap: 0.8rem; margin-top: 1.75rem; }

/* Reader ----------------------------------------------------------------- */

.reader-head { display: flex; align-items: center; gap: 0.9rem; margin-bottom: 1.25rem; }
.reader-head h2 { margin: 0; }

.reader-controls { display: grid; gap: 0.8rem; }

.reader-filters { display: grid; grid-template-columns: 1fr 1fr; gap: 0.7rem; }

.reader-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    font-size: 0.82rem;
    color: var(--text-muted);
    flex-wrap: wrap;
}

.reader-list { display: grid; gap: 0.5rem; }

.reader-item {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 14px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    overflow: hidden;
}

.reader-item summary {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.9rem 1.1rem;
    cursor: pointer;
    list-style: none;
    font-size: 0.95rem;
}

.reader-item summary::-webkit-details-marker { display: none; }
.reader-item summary:hover { background: rgba(255, 255, 255, 0.04); }
.reader-q { flex: 1; }

.status-dot {
    width: 9px; height: 9px;
    border-radius: 50%;
    flex-shrink: 0;
}

.status-new { background: rgba(255, 255, 255, 0.2); }
.status-learning { background: var(--info); }
.status-hard { background: var(--partial); }
.status-mastered { background: var(--success); }

.reader-body { padding: 0 1.1rem 1rem; }
.reader-a { color: #e2e8f0; line-height: 1.55; margin-bottom: 0.7rem; }

.reader-meta-line { display: flex; align-items: center; gap: 0.6rem; flex-wrap: wrap; font-size: 0.75rem; }

.reader-empty { text-align: center; color: var(--text-muted); padding: 2rem; }

/* Toast ------------------------------------------------------------------ */

.toast {
    position: fixed;
    left: 50%;
    bottom: calc(1.5rem + env(safe-area-inset-bottom));
    transform: translate(-50%, 140%);
    background: rgba(20, 20, 24, 0.96);
    border: 1px solid var(--glass-border);
    color: var(--text-light);
    padding: 0.8rem 1.2rem;
    border-radius: 12px;
    font-size: 0.9rem;
    max-width: min(92vw, 420px);
    text-align: center;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.5);
    transition: transform 0.3s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.3s;
    opacity: 0;
    z-index: 100;
    pointer-events: none;
}

.toast.visible { transform: translate(-50%, 0); opacity: 1; }

/* Responsive ------------------------------------------------------------- */

@media (max-width: 620px) {
    .container { padding: 1.25rem 1rem calc(1.5rem + env(safe-area-inset-bottom)); }
    .btn-group { flex-direction: column; }
    .action-buttons { flex-direction: column; }
    .dash-main { gap: 1.1rem; justify-content: center; }
    .ring-wrap { width: 112px; height: 112px; }
    .ring-label strong { font-size: 1.6rem; }
    .reader-filters { grid-template-columns: 1fr; }
    .grade-btn { font-size: 0.95rem; }
    kbd { display: none; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
    }
    .blob { animation: none; }
}

.dash-hint {
    text-align: center;
    font-size: 0.78rem;
    color: var(--text-muted);
    margin: -0.35rem 0 0.25rem;
}

/* Study screen ----------------------------------------------------------- */

.study-controls { display: grid; gap: 0.9rem; }

.study-tabs { display: flex; gap: 0.5rem; }

.study-tab {
    flex: 1;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    padding: 0.7rem 0.5rem;
    font-size: 0.92rem;
}

.study-tab:hover { background: rgba(255, 255, 255, 0.1); }

.study-tab.is-active {
    background: rgba(225, 29, 72, 0.18);
    border-color: var(--primary-red);
    color: #fff;
}

.study-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    font-size: 0.8rem;
    flex-wrap: wrap;
}

.study-body { display: grid; gap: 0.6rem; }

/* One anchor plus everything hanging off it. */
.tl-anchor {
    position: relative;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 18px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 0.4rem 0.5rem 0.5rem;
    margin-bottom: 0.6rem;
}

.tl-children {
    position: relative;
    margin-left: 1.4rem;
    padding-left: 1rem;
    border-left: 2px solid rgba(225, 29, 72, 0.28);
}

.tl-node > summary {
    display: flex;
    align-items: center;
    gap: 0.7rem;
    padding: 0.6rem 0.7rem;
    cursor: pointer;
    list-style: none;
    border-radius: 10px;
    transition: background 0.15s;
}

.tl-node > summary::-webkit-details-marker { display: none; }
.tl-node > summary:hover { background: rgba(255, 255, 255, 0.05); }

.tl-year {
    font-variant-numeric: tabular-nums;
    font-weight: 700;
    font-size: 0.95rem;
    color: var(--text-muted);
    min-width: 3.4em;
    flex-shrink: 0;
}

.tl-node.is-anchor > summary { padding: 0.8rem 0.7rem; }
.tl-node.is-anchor .tl-year { font-size: 1.45rem; color: #fda4af; }

.tl-title { flex: 1; font-size: 0.98rem; }
.tl-node.is-anchor .tl-title { font-size: 1.1rem; font-weight: 600; }

/* The whole point: the meaning stays masked until you ask for it. */
.tl-node:not([open]) .tl-real { display: none; }
.tl-node[open] .tl-mask { display: none; }
.tl-mask { color: rgba(255, 255, 255, 0.22); letter-spacing: 0.08em; }

.tl-badge {
    flex-shrink: 0;
    font-size: 0.72rem;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--glass-border);
    padding: 0.15rem 0.55rem;
    border-radius: 999px;
    white-space: nowrap;
}

.tl-node.is-anchor .tl-badge {
    color: #fda4af;
    background: rgba(225, 29, 72, 0.15);
    border-color: rgba(225, 29, 72, 0.3);
}

.tl-body { padding: 0 0.7rem 0.8rem 0.7rem; }
.tl-note { font-size: 0.92rem; line-height: 1.55; color: #d4d4d8; margin-bottom: 0.6rem; }

.tl-hook {
    font-size: 0.85rem;
    line-height: 1.5;
    color: #fcd34d;
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid rgba(245, 158, 11, 0.25);
    border-radius: 10px;
    padding: 0.55rem 0.75rem;
    margin-bottom: 0.6rem;
}

.tl-questions { margin-top: 0.75rem; }

.tl-questions-label {
    display: block;
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    color: var(--text-muted);
    margin-bottom: 0.4rem;
}

.tl-q {
    border-left: 2px solid var(--glass-border);
    padding-left: 0.7rem;
    margin-bottom: 0.4rem;
}

.tl-q > summary {
    cursor: pointer;
    font-size: 0.88rem;
    list-style: none;
    padding: 0.2rem 0;
    color: var(--text-light);
}

.tl-q > summary::-webkit-details-marker { display: none; }
.tl-q > summary:hover { color: #fda4af; }
.tl-q[open] > summary { color: #fda4af; }
.tl-q p { font-size: 0.88rem; line-height: 1.55; color: var(--text-muted); padding: 0.25rem 0 0.4rem; }

.topic-block {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    overflow: hidden;
}

.topic-block > summary {
    display: flex;
    align-items: center;
    gap: 0.7rem;
    padding: 0.95rem 1.1rem;
    cursor: pointer;
    list-style: none;
    font-weight: 600;
}

.topic-block > summary::-webkit-details-marker { display: none; }
.topic-block > summary:hover { background: rgba(255, 255, 255, 0.04); }
.topic-body { padding: 0 1.1rem 1rem; }

@media (max-width: 620px) {
    .tl-children { margin-left: 0.5rem; padding-left: 0.7rem; }
    .tl-badge { display: none; }
    .tl-node.is-anchor .tl-badge { display: inline; }
}

/* Background events sit a shade quieter than the ones that get asked about. */
.tl-node.is-extra .tl-year { opacity: 0.55; font-weight: 400; }
.tl-node.is-extra .tl-title { opacity: 0.8; }

/* Spoken form of the year: knowing the digits is not the same as saying them. */
.tl-say {
    font-size: 0.95rem;
    line-height: 1.5;
    color: #7dd3fc;
    background: rgba(56, 189, 248, 0.08);
    border: 1px solid rgba(56, 189, 248, 0.22);
    border-radius: 10px;
    padding: 0.5rem 0.75rem;
    margin-bottom: 0.6rem;
}

.tl-say span {
    display: block;
    font-size: 0.66rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-muted);
    margin-bottom: 0.15rem;
}

/* Training / date-drill tabs share the study-screen tab component. */
.config-panel .study-tabs { margin-bottom: 1.5rem; }