@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800;900&display=swap');

:root {
    --primary-color: #208af3;
    --primary-strong: #0f74dd;
    --background-color: #f8fbff;
    --card-background: rgba(255, 255, 255, 0.97);
    --text-main: #0d1830;
    --text-secondary: #566278;
    --text-muted: #758196;
    --border-color: #e5ebf5;
    --success-color: #18b46b;
    --error-color: #e83e4f;
    --fsrs-again: #e83343;
    --fsrs-hard: #e88a00;
    --fsrs-good: #157ee5;
    --fsrs-easy: #11a85b;
    --fsrs-again-bg: #fff4f5;
    --fsrs-hard-bg: #fff8e9;
    --fsrs-good-bg: #f1f8ff;
    --fsrs-easy-bg: #f0fbf3;
    --radius-xl: 30px;
    --radius-lg: 22px;
    --radius-md: 16px;
    --radius-pill: 999px;
    --bottom-nav-height: 60px;
    --shadow-subtle: 0 6px 18px rgba(22, 38, 64, 0.045);
    --shadow-soft: 0 10px 28px rgba(22, 38, 64, 0.06);
    --shadow-card: 0 18px 38px rgba(31, 49, 78, 0.11);
    --shadow-control: 0 8px 18px rgba(47, 78, 116, 0.08);
    --shadow-blue: 0 8px 18px rgba(32, 138, 243, 0.14);
    --transition-fast: 0.18s ease;
    --transition-medium: 0.28s ease;
}

* { box-sizing: border-box; }
html { min-height: 100%; background: var(--background-color); }
body {
    margin: 0;
    min-height: 100dvh;
    color: #2f3c52;
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    display: flex;
    justify-content: center;
    align-items: stretch;
    background:
        radial-gradient(circle at 18% 4%, rgba(255, 255, 255, 0.78) 0, rgba(255, 255, 255, 0) 38%),
        radial-gradient(circle at 84% 12%, rgba(230, 243, 255, 0.48) 0, rgba(230, 243, 255, 0) 36%),
        linear-gradient(180deg, #fbfdff 0%, var(--background-color) 56%, #ffffff 100%);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
a { color: inherit; }

#app {
    position: relative;
    width: 100%;
    max-width: 430px;
    min-height: 100dvh;
    padding: 14px 16px calc(var(--bottom-nav-height) + 16px + env(safe-area-inset-bottom, 0px));
    display: flex;
    flex-direction: column;
    gap: 10px;
}
#app.page-centered, #app.page-form { padding-bottom: 22px; }
#app.page-centered { justify-content: center; }

#top-menu, .app-header {
    min-height: 56px;
    width: 100%;
    display: grid;
    grid-template-columns: 48px 1fr 48px;
    align-items: center;
    gap: 12px;
    margin: 0;
    padding: 0;
}
.app-header__title, #top-menu > p {
    margin: 0;
    text-align: center;
    color: #2f3c52;
    font-size: clamp(1.08rem, 4.4vw, 1.34rem);
    line-height: 1.12;
    font-weight: 700;
    letter-spacing: -0.03em;
}
.icon-button, #add-btn a, #back-icon {
    width: 46px;
    height: 46px;
    border-radius: 15px;
    background: rgba(255, 255, 255, 0.88);
    border: 1px solid rgba(233, 239, 248, 0.86);
    color: #2f3c52;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    box-shadow: var(--shadow-control);
    backdrop-filter: blur(12px);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast), color var(--transition-fast), background var(--transition-fast);
}
.icon-button svg, #add-btn svg, #back-icon svg { width: 22px; height: 22px; stroke-width: 2.1; }
.icon-button:hover, #add-btn a:hover, #back-icon:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(45, 89, 140, 0.12); }
#add-btn { display: flex; justify-content: flex-end; }
#add-btn a { color: #4a617a; background: rgba(255, 255, 255, 0.78); box-shadow: 0 6px 16px rgba(47, 78, 116, 0.06); }
#add-btn a:hover { color: var(--primary-color); background: #fff; }
#back-icon { margin: 0; cursor: pointer; }
.back-arrow { width: 13px; height: 13px; border-left: 3px solid currentColor; border-bottom: 3px solid currentColor; transform: rotate(45deg) translateX(2px); }

.progress-card {
    width: 100%;
    min-height: 44px;
    padding: 6px 8px 6px 12px;
    display: block;
    text-decoration: none;
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.62);
    border: 1px solid rgba(228, 235, 247, 0.64);
    box-shadow: var(--shadow-subtle);
    backdrop-filter: blur(12px);
}
.progress-card__row { min-height: 30px; display: flex; align-items: center; justify-content: space-between; gap: 8px; color: var(--text-secondary); }
.progress-card[data-session-plan-toggle] .progress-card__row { cursor: pointer; border-radius: 13px; transition: background var(--transition-fast), transform var(--transition-fast); }
.progress-card[data-session-plan-toggle] .progress-card__row:active { transform: scale(.995); }
.progress-card__summary { min-width: 0; max-width: 100%; flex: 1 1 auto; display: inline-flex; align-items: baseline; gap: 6px; overflow: hidden; color: var(--text-main); white-space: nowrap; text-overflow: ellipsis; }
.progress-card__toggle-icon { width: 24px; height: 24px; flex: 0 0 24px; display: inline-flex; align-items: center; justify-content: center; color: rgba(32,138,243,.68); background: rgba(32,138,243,.065); border: 1px solid rgba(32,138,243,.10); border-radius: 50%; pointer-events: none; transition: transform var(--transition-fast), color var(--transition-fast), background var(--transition-fast); }
.progress-card__toggle-icon svg { width: 16px; height: 16px; display: block; stroke-width: 2.1; }
.progress-card[data-session-plan-toggle][aria-expanded="true"] .progress-card__toggle-icon { transform: rotate(180deg); color: var(--primary-color); background: rgba(32,138,243,.10); }
.progress-card__number, #count-cards { display: inline-block; color: var(--text-main); font-size: clamp(1.12rem, 4.2vw, 1.34rem); font-weight: 700; letter-spacing: -0.045em; vertical-align: baseline; }
.progress-card__unit { min-width: 0; overflow: hidden; color: var(--text-main); font-size: clamp(.9rem, 3.25vw, 1rem); font-weight: 600; letter-spacing: -0.02em; text-overflow: ellipsis; }
.study-mode-switch { flex: 0 0 auto; min-height: 30px; padding: 3px; display: inline-grid; grid-template-columns: repeat(2, max-content); gap: 2px; background: rgba(239,244,251,.84); border: 1px solid rgba(226,234,247,.9); border-radius: var(--radius-pill); }
.study-mode-switch__item { min-height: 24px; padding: 0 9px; display: inline-flex; align-items: center; justify-content: center; color: var(--text-secondary); border-radius: var(--radius-pill); font-size: .72rem; font-weight: 800; letter-spacing: -0.012em; text-decoration: none; transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast); }
.study-mode-switch__item.is-active { color: var(--primary-color); background: #fff; box-shadow: 0 3px 8px rgba(32,138,243,.09); }
.catchup-plan { margin-top: 8px; max-height: 180px; padding: 10px 11px; overflow: hidden; border-radius: 15px; background: rgba(32,138,243,.055); border: 1px solid rgba(32,138,243,.10); color: var(--text-secondary); opacity: 1; transition: max-height var(--transition-medium), margin-top var(--transition-medium), padding-top var(--transition-medium), padding-bottom var(--transition-medium), border-width var(--transition-medium), opacity var(--transition-fast); }
.catchup-plan.is-collapsed { margin-top: 0; max-height: 0; padding-top: 0; padding-bottom: 0; border-width: 0; opacity: 0; pointer-events: none; }
.catchup-plan.is-expanded { opacity: 1; }
.catchup-plan__head { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; color: var(--text-main); font-size: .82rem; font-weight: 700; letter-spacing: -0.015em; }
.catchup-plan__head strong { flex: 0 0 auto; color: var(--primary-color); font-size: .92rem; font-weight: 800; letter-spacing: -0.035em; }
.catchup-plan__summary { margin: 6px 0 0; color: var(--text-secondary); font-size: .78rem; line-height: 1.32; font-weight: 600; }
.catchup-plan__tail { margin: 5px 0 0; color: var(--text-muted); font-size: .72rem; line-height: 1.3; }
.session-plan { margin-top: 8px; padding-top: 8px; border-top: 1px solid rgba(226,234,247,.72); color: var(--text-secondary); font-size: .78rem; line-height: 1.2; }
.session-plan__head { display: flex; align-items: center; justify-content: space-between; gap: 10px; color: var(--text-main); font-weight: 700; }
.session-plan__head strong { color: var(--primary-color); font-size: 1rem; letter-spacing: -0.035em; }
.session-plan__grid { margin-top: 7px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 5px 9px; }
.session-plan__grid span { min-width: 0; overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.session-plan__grid b { color: var(--text-main); font-weight: 700; }
.session-plan__tail { margin-top: 7px; color: var(--text-muted); font-size: .72rem; }
#card { flex: 1 1 auto; width: 100%; min-height: 0; display: flex; flex-direction: column; align-items: stretch; justify-content: stretch; gap: 10px; perspective: 1000px; }
.card {
    position: relative;
    width: 100%;
    min-height: 292px;
    flex: 1 1 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 42px 22px 18px;
    color: #2f3c52;
    text-align: center;
    border-radius: var(--radius-xl);
    overflow: hidden;
    transition: transform var(--transition-medium), padding var(--transition-medium), min-height var(--transition-medium);
}
.card::before { content: ''; display: none; position: absolute; inset: 0; pointer-events: none; opacity: .70; }
.card > * { position: relative; z-index: 1; }
.card.card--answer-mode { min-height: 292px; padding-top: 36px; padding-bottom: 16px; gap: 8px; }
.card-action-edit { position: absolute; z-index: 2; top: 18px; right: 18px; width: 42px; height: 42px; display: inline-flex; align-items: center; justify-content: center; color: #627086; background: rgba(255,255,255,.74); border: 1px solid rgba(226,234,247,.86); border-radius: 14px; text-decoration: none; box-shadow: 0 6px 16px rgba(47,78,116,.06); backdrop-filter: blur(12px); transition: color var(--transition-fast), background var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast); }
.card-action-edit:hover { color: var(--primary-color); background: #fff; border-color: rgba(32,138,243,.18); transform: translateY(-1px); box-shadow: 0 8px 20px rgba(45,89,140,.10); }
.card-action-edit:active { transform: translateY(0); }
.card-action-edit svg { width: 20px; height: 20px; stroke-width: 2.05; }
.card.card--audio-question { justify-content: center; }
.card.card--audio-question #question:empty { display: none; }
.card.card--audio-question #bottom-area { margin-top: 4px; width: 100%; }
.card--form { flex: initial; min-height: auto; justify-content: center; align-items: stretch; gap: 24px; padding: 34px 26px; }
.card--form h2 { margin: 0 0 8px; color: var(--text-main); font-size: 1.65rem; letter-spacing: -0.03em; }
.card--form form { width: 100%; }
.form-flashes { display: grid; gap: 8px; margin-top: -8px; }
.form-flash { padding: 10px 12px; border-radius: 12px; border: 1px solid rgba(47,151,243,.18); background: #eef5ff; color: #1f5e95; font-size: .89rem; font-weight: 700; line-height: 1.3; }
.form-flash--warning { border-color: rgba(232,138,0,.25); background: #fff6e8; color: #975e00; }
.form-flash--danger { border-color: rgba(232,51,67,.24); background: #fff0f2; color: #a12a35; }
.form-flash--success { border-color: rgba(17,168,91,.22); background: #eefaf2; color: #0f7d47; }
.form-flash--info { border-color: rgba(32,138,243,.2); background: #edf6ff; color: #1f5e95; }

#question {
    --question-size: clamp(2.28rem, 9.8vw, 3.25rem);
    --question-line-height: 1.08;
    width: 100%;
    max-width: 360px;
    min-width: 0;
    margin: 0 auto;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    color: var(--text-main);
    font-size: var(--question-size);
    line-height: var(--question-line-height);
    font-weight: 900;
    letter-spacing: -0.065em;
    overflow: hidden;
    overflow-wrap: anywhere;
    word-break: normal;
    hyphens: auto;
}
#question.question-size--medium { --question-size: clamp(1.9rem, 7.7vw, 2.65rem); --question-line-height: 1.11; }
#question.question-size--small { --question-size: clamp(1.55rem, 6.2vw, 2.18rem); --question-line-height: 1.14; }
#question.question-size--tiny { --question-size: clamp(1.35rem, 5.2vw, 1.82rem); --question-line-height: 1.16; }
#question p { max-width: 100%; margin: 0; overflow-wrap: anywhere; word-break: normal; hyphens: auto; }
#question p + p { margin-top: 10px; color: var(--text-secondary); font-size: clamp(1.18rem, 5.5vw, 1.48rem); line-height: 1.22; font-weight: 500; letter-spacing: -0.025em; }
#answer { width: 100%; max-width: 330px; min-width: 0; padding: 0; margin: 0 auto; display: flex; flex-direction: column; align-items: center; gap: 7px; color: var(--text-secondary); font-size: clamp(1.06rem, 4.6vw, 1.32rem); line-height: 1.31; font-weight: 500; text-align: center; overflow-wrap: anywhere; word-break: normal; hyphens: auto; }
#answer p { max-width: 100%; overflow-wrap: anywhere; word-break: normal; hyphens: auto; }
#answer.answer-reveal { max-height: 0; opacity: 0; transform: translateY(8px); overflow: hidden; pointer-events: none; transition: max-height .34s ease, opacity .24s ease, transform .34s ease; }
#answer.answer-reveal.is-open { max-height: none; opacity: 1; transform: translateY(0); overflow: visible; pointer-events: auto; }
#answer p { width: 100%; margin: 0; color: var(--text-secondary); }
#answer p + p { margin-top: 2px; }
.card.card--audio-question #answer p:first-of-type { color: var(--text-main); font-size: clamp(1.5rem, 6vw, 1.78rem); line-height: 1.15; font-weight: 800; letter-spacing: -0.04em; }
#answer hr { width: 86px; height: 2px; border: 0; background: #a8d2fb; border-radius: var(--radius-pill); margin: 1px auto 8px; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

#audio { width: 100%; min-height: 54px; display: flex; align-items: center; justify-content: center; }
audio { display: none; }
#play-btn { width: 58px; height: 58px; padding: 14px; margin: 0; color: var(--primary-color); background: linear-gradient(180deg, #fff 0%, #f7fbff 100%); border: 1px solid rgba(226,234,247,.9); border-radius: 50%; cursor: pointer; box-shadow: 0 8px 18px rgba(32, 138, 243, 0.12), inset 0 -4px 10px rgba(32, 138, 243, 0.05); transition: transform var(--transition-fast), box-shadow var(--transition-fast), color var(--transition-fast), background var(--transition-fast); }
#play-btn:hover { transform: translateY(-2px) scale(1.04); color: #fff; background: var(--primary-color); box-shadow: var(--shadow-blue); }
#play-btn.pressed { transform: scale(.94); color: #fff; background: var(--primary-strong); }

#bottom-area { width: 100%; margin-top: 0; display: flex; flex-direction: column; align-items: stretch; gap: 8px; }
.review-actions, #buttons { width: 100%; flex: 0 0 auto; display: flex; flex-direction: column; align-items: center; gap: 12px; }
#buttons.answer-mode { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; align-items: stretch; }
button, .button-like, input[type='submit'] { width: min(100%, 280px); min-height: 52px; margin: 0 auto; padding: 14px 24px; display: inline-flex; align-items: center; justify-content: center; gap: 10px; border: 0; border-radius: 18px; font-family: inherit; font-size: 1rem; font-weight: 600; line-height: 1; letter-spacing: -0.012em; color: #fff; text-align: center; text-decoration: none; cursor: pointer; box-shadow: var(--shadow-blue); transition: transform var(--transition-fast), box-shadow var(--transition-fast), background var(--transition-fast), opacity var(--transition-fast); }
button:hover, .button-like:hover, input[type='submit']:hover { transform: translateY(-2px); }
button:active, .button-like:active, input[type='submit']:active { transform: translateY(0); }
button:disabled { cursor: not-allowed; opacity: .62; transform: none; }
.answer-button.is-selected:disabled { opacity: 1; }
button:focus-visible, .button-like:focus-visible, input[type='submit']:focus-visible, .icon-button:focus-visible, #add-btn a:focus-visible, #back-icon:focus-visible, .bottom-nav__item:focus-visible, .desktop-nav-row:focus-visible, .filter-row:focus-visible, .desktop-link-card:focus-visible, .card-action-edit:focus-visible, .study-mode-switch__item:focus-visible { outline: 3px solid rgba(32,138,243,.28); outline-offset: 3px; }
button.blue-btn, .button-like.blue-btn, input.blue-btn { background: linear-gradient(135deg, #4bb2ff, var(--primary-color)); }
button.blue-btn:hover, .button-like.blue-btn:hover, input.blue-btn:hover { box-shadow: 0 10px 24px rgba(47,151,243,.22); }
.blue-btn--secondary { color: var(--primary-color); background: rgba(32,138,243,.08) !important; box-shadow: none; }
.keyboard-hint { display: none; min-width: 42px; padding: 4px 8px; color: rgba(255,255,255,.9); background: rgba(255,255,255,.16); border: 1px solid rgba(255,255,255,.28); border-radius: 9px; font-family: inherit; font-size: .72rem; font-weight: 600; line-height: 1; }
.answer-button__shortcut { display: none; margin-left: auto; min-width: 25px; height: 25px; align-items: center; justify-content: center; color: currentColor; background: rgba(255,255,255,.74); border: 1px solid rgba(255,255,255,.86); border-radius: 9px; font-size: .78rem; font-weight: 700; line-height: 1; }
.save-btn { margin-bottom: 12px; }
#buttons.answer-mode .answer-button { position: relative; width: 100%; min-height: 54px; padding: 9px 11px; justify-content: flex-start; gap: 8px; border: 1px solid rgba(255,255,255,.70); border-radius: 19px; box-shadow: 0 7px 18px rgba(42,59,85,.05); overflow: hidden; }
.answer-button__icon { width: 34px; height: 34px; flex: 0 0 auto; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; background: rgba(255,255,255,.70); box-shadow: inset 0 1px 0 rgba(255,255,255,.9); }
.answer-button__icon svg { width: 20px; height: 20px; display: block; stroke-width: 2.35; }
.answer-button__content { min-width: 0; display: flex; flex-direction: column; align-items: flex-start; gap: 2px; }
.btn-label { font-size: clamp(1.02rem, 3.7vw, 1.16rem); font-weight: 750; line-height: 1.06; letter-spacing: -0.028em; }
.next { color: #6d778b; font-size: clamp(.72rem, 2.8vw, .82rem); font-weight: 520; line-height: 1.06; letter-spacing: -0.01em; }
.answer-button--again { color: var(--fsrs-again); background: linear-gradient(135deg, #fff8f8, var(--fsrs-again-bg)); border-color: rgba(232, 51, 67, .18) !important; }
.answer-button--hard { color: var(--fsrs-hard); background: linear-gradient(135deg, #fffaf1, var(--fsrs-hard-bg)); border-color: rgba(232, 138, 0, .2) !important; }
.answer-button--good { color: var(--fsrs-good); background: linear-gradient(135deg, #f8fcff, var(--fsrs-good-bg)); border-color: rgba(21, 126, 229, .18) !important; }
.answer-button--easy { color: var(--fsrs-easy); background: linear-gradient(135deg, #f6fff8, var(--fsrs-easy-bg)); border-color: rgba(17, 168, 91, .18) !important; }
.answer-button::after { content: ""; position: absolute; inset: 0; pointer-events: none; border-radius: inherit; opacity: 0; background: currentColor; transition: opacity var(--transition-fast); }
.answer-button:hover { transform: translateY(-2px); box-shadow: 0 10px 22px rgba(42,59,85,.08); }
.answer-button.is-selected { transform: translateY(-1px) scale(.985); box-shadow: 0 12px 24px rgba(42,59,85,.10), inset 0 0 0 1px currentColor; }
.answer-button.is-selected::after { opacity: .08; }
.answer-button.is-difficult { animation: selectedPulse .16s ease-out; }
.answer-button.is-positive { animation: selectedPulse .18s ease-out; }
@keyframes selectedPulse { from { transform: scale(.98); } to { transform: translateY(-1px) scale(.985); } }

.form-group { margin-bottom: 1rem; width: 100%; }
.form-group label, .login-container label { display: block; margin: 0 0 8px 4px; color: var(--text-secondary); font-size: .92rem; font-weight: 700; }
.form-control, input[type='text'], input[type='password'] { width: 100%; min-height: 56px; padding: 14px 17px; color: var(--text-main); background: rgba(250,252,255,.92); border: 1px solid var(--border-color); border-radius: 16px; font-family: inherit; font-size: 1rem; font-weight: 600; outline: none; transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background var(--transition-fast); }
.form-control:focus, input[type='text']:focus, input[type='password']:focus { border-color: rgba(47,151,243,.72); background: #fff; box-shadow: 0 0 0 4px rgba(47,151,243,.10); }
.form-check { margin: 0 0 1rem; display: flex; align-items: center; gap: 10px; color: var(--text-secondary); }
.form-check__input { width: 18px; height: 18px; margin: 0; accent-color: var(--primary-color); }
.form-check__label { margin: 0; font-size: .9rem; font-weight: 600; cursor: pointer; }
.edit-icon { display: inline-flex; align-items: center; justify-content: center; margin-left: 10px; color: var(--primary-color); text-decoration: none; font-size: 1rem; opacity: .78; transition: opacity var(--transition-fast), transform var(--transition-fast); }
.edit-icon:hover { opacity: 1; transform: scale(1.05); }
.spinner, .spinner-border { display: block; width: 48px; height: 48px; border: 4px solid rgba(47,151,243,.12); border-top-color: var(--primary-color); border-radius: 50%; animation: spin 1s linear infinite; margin: 24px auto 0; align-self: center; }
@keyframes spin { from { transform: rotate(0); } to { transform: rotate(360deg); } }
.toast-message, .alert { position: fixed; top: 22px; left: 50%; transform: translateX(-50%); min-width: min(340px, calc(100vw - 32px)); display: none; z-index: 9999; padding: 15px 18px; color: #fff; background: var(--success-color); border: 0; border-radius: 16px; box-shadow: var(--shadow-soft); font-size: .98rem; font-weight: 800; text-align: center; }
.toast-message.error, .alert-danger { background: var(--error-color); }
.toast-message.show, .alert.show { display: block; animation: toastIn .24s ease-out; }
@keyframes toastIn { from { opacity: 0; transform: translate(-50%, -10px); } to { opacity: 1; transform: translate(-50%, 0); } }
#network-error-banner { border: 1px solid rgba(239,77,87,.22) !important; border-radius: 18px !important; color: #a12831 !important; background: #fff0f1 !important; box-shadow: var(--shadow-soft); }

.bottom-nav { position: fixed; left: 50%; bottom: max(8px, env(safe-area-inset-bottom, 0px)); transform: translateX(-50%); z-index: 20; width: min(386px, calc(100vw - 24px)); height: var(--bottom-nav-height); padding: 5px 8px; display: grid; grid-template-columns: repeat(3, 1fr); align-items: center; gap: 4px; background: rgba(255,255,255,.84); border: 1px solid rgba(229,236,247,.74); border-radius: 18px; box-shadow: 0 8px 22px rgba(31,49,78,.06); backdrop-filter: blur(16px); }
.bottom-nav__item { min-width: 0; min-height: 44px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 2px; color: #6f7a90; text-decoration: none; font-size: .72rem; font-weight: 600; border-radius: 14px; transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast); }
.bottom-nav__item svg { width: 19px; height: 19px; stroke-width: 2.05; }
.bottom-nav__item:hover { transform: translateY(-1px); }
.bottom-nav__item.is-active { color: var(--primary-color); background: rgba(32,138,243,.08); box-shadow: none; }
.bottom-nav__item.is-active svg { filter: none; }


@media (hover: hover) and (pointer: fine) {
    .study-mode-switch__item:hover { color: var(--primary-color); background: rgba(255,255,255,.82); transform: translateY(-1px); }
    .filter-row:not(:disabled):hover, .desktop-link-card:hover { box-shadow: inset 0 0 0 1px rgba(32,138,243,.08); }
}

.desktop-panel { display: none; }
.review-dashboard, .review-main { width: 100%; min-width: 0; }
.review-dashboard { flex: 1 1 auto; min-height: 0; display: flex; }
.review-main { flex: 1 1 auto; min-height: 0; display: flex; flex-direction: column; gap: 10px; }
.desktop-panel__eyebrow { color: var(--primary-color); font-size: .72rem; font-weight: 700; letter-spacing: .09em; text-transform: uppercase; }
.desktop-panel h2 { margin: 6px 0 14px; color: var(--text-main); font-size: 1.22rem; line-height: 1.1; font-weight: 700; letter-spacing: -0.04em; }
.desktop-nav-list { display: flex; flex-direction: column; gap: 6px; margin-bottom: 20px; padding-bottom: 18px; border-bottom: 1px solid rgba(226,234,247,.82); }
.desktop-nav-row { min-height: 44px; padding: 0 12px; display: flex; align-items: center; gap: 10px; color: var(--text-secondary); border-radius: 14px; font-size: .94rem; font-weight: 600; letter-spacing: -0.012em; text-decoration: none; transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast); }
.desktop-nav-row svg { width: 20px; height: 20px; flex: 0 0 auto; stroke-width: 2.05; }
.desktop-nav-row:hover { color: var(--text-main); background: rgba(255,255,255,.68); transform: none; }
.desktop-nav-row.is-active { color: var(--primary-color); background: rgba(32,138,243,.09); }
.filter-list { display: flex; flex-direction: column; gap: 8px; }
.filter-row { width: 100%; min-height: 46px; padding: 0 13px; display: flex; align-items: center; justify-content: space-between; gap: 12px; color: var(--text-secondary); background: transparent; border: 0; border-radius: 14px; font-family: inherit; font-size: .94rem; font-weight: 600; text-decoration: none; box-shadow: none; cursor: pointer; }
.filter-row:hover { transform: none; background: rgba(255,255,255,.7); }
.filter-row:disabled { cursor: default; opacity: 1; }
.filter-row.is-active { color: var(--primary-color); background: rgba(32,138,243,.10); }
.filter-row__label { overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.filter-row__count { flex: 0 0 auto; min-width: 32px; padding: 5px 9px; color: var(--text-main); background: rgba(255,255,255,.78); border: 1px solid rgba(229,236,247,.92); border-radius: var(--radius-pill); font-size: .78rem; line-height: 1; text-align: center; }
.filter-row.is-active .filter-row__count { color: var(--primary-color); border-color: rgba(32,138,243,.22); }
.filter-row__count--muted { min-width: auto; color: var(--text-muted); font-size: .72rem; }
.folder-block { margin-top: 20px; padding-top: 18px; border-top: 1px solid rgba(226,234,247,.82); }
.folder-block__title { margin-bottom: 12px; color: var(--text-secondary); font-size: .8rem; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; }
.folder-pill { width: 100%; min-height: 42px; margin: 0 0 8px; padding: 0 12px; justify-content: flex-start; gap: 10px; color: var(--text-secondary); background: rgba(255,255,255,.58); border: 1px solid rgba(229,236,247,.9); border-radius: 15px; box-shadow: none; font-size: .9rem; font-weight: 600; }
.folder-pill:hover { transform: none; }
.folder-pill:disabled { cursor: default; opacity: 1; }
.folder-pill span { width: 9px; height: 9px; border-radius: 50%; background: var(--primary-color); box-shadow: 0 0 0 4px rgba(32,138,243,.10); }
.desktop-stat-card { padding: 14px 15px; display: flex; flex-direction: column; gap: 7px; background: rgba(255,255,255,.62); border: 1px solid rgba(229,236,247,.82); border-radius: 16px; }
.desktop-stat-card span { color: var(--text-secondary); font-size: .82rem; font-weight: 500; }
.desktop-stat-card strong { color: var(--text-main); font-size: 1.42rem; line-height: 1; font-weight: 700; letter-spacing: -0.045em; }
.desktop-stat-card--primary { min-height: 96px; justify-content: center; background: linear-gradient(135deg, #f9fcff, #f1f8ff); border-color: rgba(32,138,243,.13); }
.desktop-stat-card--primary strong { color: var(--primary-color); font-size: 2.4rem; }
.desktop-progress-track { height: 8px; margin: 14px 0 8px; overflow: hidden; background: #e7edf7; border-radius: var(--radius-pill); }
.desktop-progress-track span { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg, #238ff2, #55b4f8); box-shadow: none; }
.desktop-progress-hint { margin-bottom: 16px; color: var(--text-secondary); font-size: .78rem; font-weight: 600; letter-spacing: -0.01em; }
.desktop-progress-hint--plan { margin-top: 10px; padding: 10px 12px; color: var(--text-main); background: rgba(32,138,243,.055); border: 1px solid rgba(32,138,243,.10); border-radius: 14px; line-height: 1.3; }
.desktop-stat-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
.repeat-preview { margin-top: 22px; padding-top: 22px; border-top: 1px solid rgba(226,234,247,.9); }
.repeat-preview h3 { margin: 0 0 12px; color: var(--text-main); font-size: 1.02rem; font-weight: 700; letter-spacing: -0.035em; }
.repeat-preview__item { min-height: 42px; display: flex; align-items: center; justify-content: space-between; gap: 12px; border-bottom: 1px solid rgba(226,234,247,.72); }
.repeat-preview__item:last-child { border-bottom: 0; }
.repeat-preview__item span { color: var(--text-secondary); font-size: .9rem; font-weight: 500; }
.repeat-preview__item strong { color: var(--text-main); font-size: .94rem; font-weight: 700; text-align: right; }
.desktop-link-card { margin-top: auto; min-height: 46px; display: inline-flex; align-items: center; justify-content: center; color: var(--primary-color); background: rgba(32,138,243,.08); border-radius: 14px; font-size: .92rem; font-weight: 700; text-decoration: none; }

.empty-state { min-height: calc(100dvh - 180px); display: flex; flex-direction: column; justify-content: center; align-items: center; gap: 16px; padding: 36px 26px; text-align: center; }
.empty-state__icon { width: 76px; height: 76px; border-radius: 24px; display: inline-flex; align-items: center; justify-content: center; color: var(--success-color); background: var(--fsrs-easy-bg); font-size: 2.1rem; }
.empty-state h1 { margin: 0; font-size: 1.9rem; letter-spacing: -0.04em; }
.empty-state p { margin: 0; color: var(--text-secondary); font-weight: 600; line-height: 1.45; }
.empty-state__note:empty { display: none; }
.empty-state__note { max-width: 280px; font-size: .9rem; }

.app--stat { gap: 12px; }
.app--stat .stat-page { width: 100%; min-width: 0; flex: 1 1 auto; display: flex; flex-direction: column; gap: 14px; padding: 4px 0 8px; }
.app--stat .stat-summary { display: grid; grid-template-columns: minmax(0, 1fr); gap: 12px; }
.app--stat .stat-total { min-height: 132px; padding: 20px; display: flex; flex-direction: column; justify-content: flex-end; align-items: flex-start; border-radius: 24px; background: linear-gradient(145deg, rgba(255,255,255,.94), rgba(241,248,255,.84)); border: 1px solid rgba(225,235,248,.9); box-shadow: var(--shadow-subtle); text-align: left; }
.app--stat .stat-total__label { color: var(--text-secondary); font-size: .84rem; font-weight: 700; letter-spacing: .02em; }
.app--stat .stat-total__value { display: block; margin-top: 8px; color: var(--text-main); font-size: 3.35rem; line-height: .9; font-weight: 850; letter-spacing: -0.06em; }
.app--stat .stat-total__hint { margin-top: 9px; color: var(--text-muted); font-size: .86rem; font-weight: 600; }
.app--stat .stat-section { width: 100%; min-width: 0; padding: 16px; border: 1px solid rgba(225,235,248,.9); border-radius: 22px; background: rgba(255,255,255,.68); box-shadow: var(--shadow-subtle); backdrop-filter: blur(12px); }
.app--stat .stat-section__header { margin-bottom: 13px; display: flex; align-items: flex-end; justify-content: space-between; gap: 12px; text-align: left; }
.app--stat .stat-section__header h2 { margin: 0; min-width: 0; color: var(--text-main); font-size: 1.08rem; line-height: 1.12; font-weight: 800; letter-spacing: -0.03em; }
.app--stat .stat-section__eyebrow { flex: 0 0 auto; color: var(--primary-color); font-size: .72rem; font-weight: 800; letter-spacing: .07em; text-transform: uppercase; }
.app--stat .scheduler-metrics-grid { display: grid; grid-template-columns: minmax(0, 1fr); gap: 8px; }
.app--stat .scheduler-metric { min-width: 0; min-height: 54px; padding: 10px 12px; display: flex; align-items: center; justify-content: space-between; gap: 14px; border: 1px solid rgba(232,238,248,.92); border-radius: 15px; background: rgba(255,255,255,.64); }
.app--stat .scheduler-metric__label { min-width: 0; color: #5c687c; font-size: .82rem; line-height: 1.24; font-weight: 650; letter-spacing: -0.01em; overflow-wrap: anywhere; }
.app--stat .scheduler-metric__value { flex: 0 0 auto; color: var(--text-main); font-size: 1.05rem; line-height: 1; font-weight: 760; letter-spacing: -0.025em; text-align: right; font-variant-numeric: tabular-nums; }
.app--stat .scheduler-metric__value.is-empty { padding: 5px 8px; color: var(--text-muted); background: rgba(117,129,150,.08); border-radius: var(--radius-pill); font-size: .78rem; font-weight: 650; letter-spacing: 0; }
.app--stat .stat-table-scroll { width: 100%; max-width: 100%; margin-top: 12px; overflow: hidden; border: 1px solid rgba(229,236,247,.9); border-radius: 16px; background: rgba(255,255,255,.74); }
.app--stat .stat-table { width: 100%; border-collapse: separate; border-spacing: 0; overflow: hidden; background: rgba(255,255,255,.74); border: 1px solid rgba(229,236,247,.9); border-radius: 16px; box-shadow: none; }
.app--stat .stat-table-scroll .stat-table { table-layout: fixed; border: 0; border-radius: 0; }
.app--stat .stat-table th, .app--stat .stat-table td { padding: 12px 13px; text-align: left; border-bottom: 1px solid #edf2fa; white-space: nowrap; }
.app--stat .stat-table th { color: var(--text-secondary); background: rgba(248,251,255,.92); font-size: .72rem; font-weight: 800; text-transform: uppercase; letter-spacing: .055em; }
.app--stat .stat-table tr:last-child td { border-bottom: none; }
.app--stat .stat-table td { color: var(--text-main); font-size: .93rem; font-weight: 650; }
.app--stat .stat-table td.count-col, .app--stat .stat-table th.count-col { text-align: right; }
.app--stat .stat-table td.count-col { color: var(--primary-color); font-weight: 850; }
.app--stat .scheduler-calibration th, .app--stat .scheduler-calibration td { padding: 10px 8px; white-space: normal; }
.app--stat .scheduler-calibration th:first-child, .app--stat .scheduler-calibration td:first-child { width: 43%; }
.app--stat .scheduler-calibration th.count-col, .app--stat .scheduler-calibration td.count-col { width: 19%; }
.app--stat .scheduler-calibration td { font-size: .82rem; line-height: 1.22; }
.app--stat .scheduler-calibration td:first-child { color: var(--text-secondary); font-weight: 700; }
.overlay-popup { position: fixed; inset: 0; display: none; align-items: center; justify-content: center; z-index: 9999; background: rgba(15,23,42,.22); backdrop-filter: blur(8px); }
.popup-card { padding: 18px 26px; color: #fff; background: #172033; border-radius: 18px; box-shadow: var(--shadow-card); }
.popup-title { font-size: 1.08rem; font-weight: 800; }


@media (min-width: 960px) {
    body { justify-content: center; }
    #app { max-width: 760px; padding: 32px 36px calc(var(--bottom-nav-height) + 24px + env(safe-area-inset-bottom, 0px)); }
    #app.page-centered, #app.page-form { max-width: 430px; padding: 32px 18px 42px; }
    #app.app--stat { max-width: 820px; }
    .app--stat .stat-page { gap: 16px; }
    .app--stat .stat-total { min-height: 150px; padding: 24px; }
    .app--stat .stat-total__value { font-size: 4rem; }
    .app--stat .scheduler-metrics-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
    .app--stat .scheduler-metric { min-height: 82px; align-items: flex-start; flex-direction: column; gap: 10px; }
    .app--stat .scheduler-metric__value { text-align: left; }
    #app.app--review { max-width: 1180px; padding: 32px 36px 42px; }
    .review-dashboard { min-height: calc(100dvh - 74px); display: grid; grid-template-columns: minmax(240px, 280px) minmax(420px, 540px) minmax(236px, 296px); align-items: stretch; justify-content: center; gap: 24px; }
    .desktop-panel { min-height: 0; padding: 22px; display: flex; flex-direction: column; background: rgba(255,255,255,.66); border: 1px solid rgba(229,236,247,.80); border-radius: 24px; box-shadow: var(--shadow-subtle); backdrop-filter: blur(12px); }
    .review-main { min-height: 0; }
    #app.app--review #top-menu { min-height: 58px; grid-template-columns: 58px 1fr 58px; }
    #app.app--review .app-header__title { font-size: 1.46rem; }
    #app.app--review .icon-button, #app.app--review #add-btn a { width: 50px; height: 50px; border-radius: 17px; }
    #app.app--review #card { flex: 1; min-height: 560px; }
    .card { background: var(--card-background); border: 1px solid rgba(223, 232, 246, 0.9); box-shadow: var(--shadow-card); transition: transform var(--transition-medium), padding var(--transition-medium), min-height var(--transition-medium), box-shadow var(--transition-medium); }
    .card::before { display: block; background: radial-gradient(circle at 50% 0%, rgba(255,255,255,.94), rgba(255,255,255,0) 34%), linear-gradient(180deg, rgba(255,255,255,.62), rgba(247,251,255,.24)); }
    #app.app--review .card { min-height: 430px; }
    #app.app--review #buttons.answer-mode { gap: 14px; }
    #app.app--review .keyboard-hint { display: inline-flex; }
    #app.app--review .answer-button__shortcut { display: inline-flex; }
    #app.app--review .bottom-nav { display: none; }
    #app.app--review .bottom-nav__item { min-height: 58px; gap: 4px; border-radius: 15px; font-size: .68rem; letter-spacing: -0.015em; }
    #app.app--review .bottom-nav__item svg { width: 21px; height: 21px; }
    #app.app--review .bottom-nav__item.is-active { background: rgba(32,138,243,.09); box-shadow: inset 0 0 0 1px rgba(32,138,243,.08); }
    #mobile-session-plan { display: none !important; }
    .progress-card[data-session-plan-toggle] .progress-card__row { cursor: default; }
    .progress-card__toggle-icon { display: none; }
}

@media (min-width: 1200px) {
    .review-dashboard { grid-template-columns: 280px minmax(460px, 560px) 300px; gap: 26px; }
    #app.app--review .card { min-height: 470px; }
}

@media (min-width: 960px) and (max-width: 1100px) {
    #app.app--review { padding-right: 24px; }
    .review-dashboard { grid-template-columns: minmax(210px, .9fr) minmax(320px, 1.45fr) minmax(180px, .9fr); gap: 14px; }
    .desktop-panel { padding: 18px; }
    #question { --question-size: clamp(2rem, 4.2vw, 2.78rem); }
}

@media (max-width: 959px) {
    #app.app--review { padding-top: 10px; gap: 8px; }
    #app.app--review .review-main { gap: 8px; }
    #app.app--review #top-menu { min-height: 44px; grid-template-columns: 42px 1fr 42px; gap: 8px; }
    #app.app--review .app-header__title { font-size: clamp(1rem, 4vw, 1.18rem); letter-spacing: -0.025em; }
    #app.app--review .icon-button, #app.app--review #add-btn a { width: 40px; height: 40px; border-radius: 14px; box-shadow: 0 5px 14px rgba(47,78,116,.055); }
    #app.app--review .icon-button svg, #app.app--review #add-btn svg { width: 19px; height: 19px; stroke-width: 2.05; }
    #app.app--review .progress-card { min-height: 36px; padding: 4px 6px 4px 10px; border-radius: 15px; background: rgba(255,255,255,.56); box-shadow: none; }
    #app.app--review .progress-card__row { min-height: 28px; gap: 6px; }
    #app.app--review .progress-card__summary { gap: 5px; }
    #app.app--review .progress-card__toggle-icon { width: 20px; height: 20px; flex-basis: 20px; }
    #app.app--review .progress-card__toggle-icon svg { width: 13px; height: 13px; }
    #app.app--review .progress-card__number, #app.app--review #count-cards { font-size: clamp(1.02rem, 3.8vw, 1.18rem); letter-spacing: -0.035em; }
    #app.app--review .progress-card__unit { font-size: clamp(.82rem, 2.9vw, .92rem); font-weight: 600; letter-spacing: -0.012em; }
    #app.app--review .study-mode-switch { min-height: 26px; padding: 2px; gap: 1px; border-color: rgba(226,234,247,.78); }
    #app.app--review .study-mode-switch__item { min-height: 22px; padding: 0 8px; font-size: .68rem; font-weight: 750; }
    #app.app--review .catchup-plan { margin-top: 6px; padding: 9px 10px; border-radius: 13px; }
    #app.app--review .catchup-plan.is-collapsed { margin-top: 0; padding-top: 0; padding-bottom: 0; }
}

@media (max-width: 430px) {
    #app { padding-left: 16px; padding-right: 16px; gap: 11px; }
    #top-menu, .app-header { grid-template-columns: 54px 1fr 54px; }
    .icon-button, #add-btn a, #back-icon { width: 50px; height: 50px; border-radius: 17px; }
    .progress-card { min-height: 42px; padding: 5px 7px 5px 11px; }
    .app-header__title, #top-menu > p { font-size: clamp(1.1rem, 4.7vw, 1.34rem); }
    #app.app--review { padding-top: 10px; gap: 8px; }
    #app.app--review #top-menu { min-height: 44px; grid-template-columns: 42px 1fr 42px; gap: 8px; }
    #app.app--review .icon-button, #app.app--review #add-btn a { width: 40px; height: 40px; border-radius: 14px; }
    #app.app--review .app-header__title { font-size: clamp(1rem, 4vw, 1.18rem); }
    #app.app--review .progress-card { min-height: 36px; padding: 4px 6px 4px 10px; }
    .card { min-height: 282px; padding-left: 20px; padding-right: 20px; }
    .card.card--answer-mode { min-height: 280px; padding-top: 34px; padding-bottom: 14px; }
    #buttons.answer-mode .answer-button { min-height: 54px; padding-left: 11px; padding-right: 11px; gap: 8px; }
    .answer-button__icon { width: 34px; height: 34px; }
    .bottom-nav { height: 58px; }
    .bottom-nav__item { min-height: 42px; font-size: .7rem; }
}
@media (max-width: 370px) {
    .app--stat .stat-total { min-height: 122px; padding: 18px; }
    .app--stat .stat-total__value { font-size: 2.85rem; }
    .app--stat .stat-section { padding: 14px; }
    .progress-card__row { gap: 7px; }
    .progress-card__summary { gap: 6px; }
    #app.app--review .progress-card__row { gap: 5px; }
    #app.app--review .progress-card__summary { gap: 4px; }
    #buttons.answer-mode { gap: 8px; }
    #buttons.answer-mode .answer-button { min-height: 54px; }
    .answer-button__icon { width: 34px; height: 34px; }
    .study-mode-switch__item { padding: 0 7px; }
    #app.app--review .study-mode-switch__item { padding: 0 6px; }
}
@media (max-height: 740px) {
    #app { gap: 12px; padding-top: 12px; }
    #top-menu, .app-header { min-height: 56px; }
    .progress-card { min-height: 42px; padding-top: 5px; padding-bottom: 5px; }
    .card { min-height: 268px; padding-top: 36px; padding-bottom: 14px; }
    .card.card--answer-mode { min-height: 266px; padding-top: 32px; }
    #audio { min-height: 48px; }
    #play-btn { width: 54px; height: 54px; padding: 13px; }
    #buttons.answer-mode .answer-button { min-height: 54px; }
}

@media (max-width: 959px) and (max-height: 740px) {
    #app.app--review { gap: 7px; padding-top: 8px; }
    #app.app--review #top-menu { min-height: 42px; }
    #app.app--review .progress-card { min-height: 34px; padding-top: 3px; padding-bottom: 3px; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; scroll-behavior: auto !important; transition-duration: .001ms !important; }
}