:root {
        --fc-bg: #ffffff;
        --fc-surface: #ffffff;
        --fc-surface-soft: #f8fbff;
        --fc-border: #dfe7f5;
        --fc-text: #122b5c;
        --fc-text-soft: #5c6f92;
        --fc-blue: #2563eb;
        --fc-green: #16a34a;
        --fc-green-soft: #eaf8ef;
        --fc-red: #e05555;
        --fc-red-soft: #fff1f1;
        --fc-purple-soft: #f1e8ff;
        --fc-shadow: 0 8px 24px rgba(18, 43, 92, 0.06);
        --fc-radius-xl: 22px;
    }

    body { background: var(--fc-bg); color: var(--fc-text); }

    .app-main {
        max-width: 1200px;
    }

    .fc-login-btn {
        border: 1px solid var(--fc-border);
        border-radius: 999px;
        padding: 0.5rem 0.85rem;
        font-weight: 700;
        font-size: 0.86rem;
        color: var(--fc-text);
        background: #fff;
        transition: 0.2s ease;
    }

    .fc-login-btn:hover {
        background: var(--fc-surface-soft);
        border-color: #ced9f0;
    }

    .fc-section { padding: 46px 0; }

    .fc-card {
        background: #ffffff;
        border: 1px solid #dfe8f7;
        border-radius: 20px;
        box-shadow: 0 10px 28px rgba(20, 54, 120, 0.055);
    }

    .fc-hero { padding: 28px; background: linear-gradient(165deg, #f7faff 0%, #f2f7ff 100%); position: relative; border-radius: 22px; }

    .fc-hero-title {
        font-size: clamp(2.1rem, 4vw, 4.1rem);
        line-height: 1.04;
        font-weight: 800;
        letter-spacing: -0.03em;
        margin-bottom: 1rem;
        max-width: 560px;
    }

    .fc-hero-title-accent { color: #1d4ed8; }

    .fc-hero-rocket {
        width: 0.9em;
        height: 0.9em;
        vertical-align: -0.06em;
        margin-left: 0.12em;
    }

    .fc-hero-subtitle {
        font-size: 1.24rem;
        line-height: 1.45;
        color: var(--fc-text);
        max-width: 470px;
        margin-bottom: 1.4rem;
    }

    .fc-primary-btn {
        display: inline-flex;
        align-items: center;
        gap: 0.7rem;
        min-height: 54px;
        padding: 0 1.3rem;
        border-radius: 14px;
        background: linear-gradient(180deg, #22c55e 0%, #16a34a 100%);
        color: #fff;
        font-weight: 700;
        font-size: 1rem;
        box-shadow: 0 10px 24px rgba(34, 197, 94, 0.2);
        border: 0;
        transition: 0.2s ease;
        text-decoration: none;
    }

.fc-primary-btn:hover { color: #fff; transform: translateY(-1px); background: linear-gradient(180deg, #1fb455 0%, #15803d 100%); }

.fc-primary-btn:disabled { opacity: .75; }

.fc-primary-btn--full {
    width: 100%;
    justify-content: center;
}

.fc-secondary-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    min-height: 54px;
    padding: 0 1.25rem;
    border-radius: 14px;
    background: #eef2f7;
    color: #31435f;
    font-weight: 700;
    font-size: 1rem;
    border: 1px solid #d6dfec;
    transition: 0.2s ease;
}

.fc-secondary-btn:hover {
    background: #e3e9f2;
    color: #20324f;
}

.fc-landing-hero {
    height: 920px;
    min-height: 920px;
    display: flex;
    justify-content: center;
    align-items: center;
    padding-top: 0;
    padding-bottom: 0;
    position: relative;
    overflow: hidden;
    background: #ffffff;
    padding: 0;
    width: 100vw;
    margin-left: calc(50% - 50vw);
    margin-right: calc(50% - 50vw);
}

.fc-landing-hero::before {
    content: "";
    position: absolute;
    inset: auto -10% -18% -10%;
    height: 34%;
    background-image:
        linear-gradient(rgba(73, 125, 215, 0.045) 1px, transparent 1px),
        linear-gradient(90deg, rgba(73, 125, 215, 0.045) 1px, transparent 1px);
    background-size: 64px 64px;
    transform: perspective(620px) rotateX(58deg);
    transform-origin: bottom;
    mask-image: linear-gradient(to top, #000, transparent);
    z-index: 0;
    pointer-events: none;
}

.fc-landing-hero::after {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle at 11% 22%, rgba(47, 107, 255, 0.12) 0 3px, transparent 4px),
        radial-gradient(circle at 84% 18%, rgba(47, 107, 255, 0.1) 0 2px, transparent 3px),
        radial-gradient(circle at 17% 76%, rgba(33, 196, 90, 0.12) 0 3px, transparent 4px),
        radial-gradient(circle at 74% 70%, rgba(255, 189, 35, 0.12) 0 3px, transparent 4px),
        radial-gradient(circle at 90% 42%, rgba(47, 107, 255, 0.08) 0 4px, transparent 5px);
    z-index: 0;
    pointer-events: none;
}

.fc-landing-hero-copy {
    width: min(680px, 100%);
    margin: 0 auto;
    text-align: center;
    position: relative;
    z-index: 5;
}

.fc-landing-hero-eyebrow {
    display: inline-flex;
    align-items: center;
    padding: 0.32rem 0.78rem;
    border-radius: 999px;
    border: 1px solid #d7e2f3;
    background: #f6f9ff;
    color: #48608a;
    font-size: 0.82rem;
    font-weight: 700;
    margin-bottom: 0.9rem;
}

.fc-landing-hero-title {
    color: #102754;
    font-size: clamp(2rem, 4vw, 3.7rem);
    line-height: 1.02;
    font-weight: 900;
    margin-bottom: 1rem;
}

.fc-landing-hero-text {
    color: #52678f;
    font-size: 1.12rem;
    line-height: 1.5;
    margin-bottom: 1.35rem;
}

.fc-landing-hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

.fc-hero-mobile-features {
    display: none;
}

.fc-hero-live-layer {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
}

.fc-hero-orbit {
    position: absolute;
    width: min(980px, 78vw);
    aspect-ratio: 1.9;
    border: 1px solid rgba(64, 129, 255, 0.12);
    border-radius: 50%;
    transform: rotate(-5deg);
    top: 52%;
    left: 50%;
    translate: -50% -52%;
}

.fc-hero-orbit::after {
    content: "";
    position: absolute;
    inset: 7%;
    border: 1px dashed rgba(64, 129, 255, 0.1);
    border-radius: 50%;
}

.fc-hero-particle {
    position: absolute;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(47, 107, 255, 0.18);
    animation: fcDrift 9s ease-in-out infinite;
    z-index: 0;
}

.fc-hero-particle.p1 { top: 4%; right: 8%; }
.fc-hero-particle.p2 { top: 31%; left: 17%; background: rgba(255, 189, 35, 0.32); animation-delay: -2s; }
.fc-hero-particle.p3 { bottom: 10%; right: 15%; background: rgba(33, 196, 90, 0.2); animation-delay: -4s; }
.fc-hero-particle.p4 { bottom: 11%; left: 12%; background: rgba(47, 107, 255, 0.26); animation-delay: -6s; }

.fc-hero-bubble-icon {
    position: absolute;
    z-index: 2;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid rgba(178, 199, 234, 0.48);
    color: #2f6bff;
    font-size: 1.05rem;
    animation: fcFloat 5.8s ease-in-out infinite;
}

.fc-hero-bubble-icon.i1 { top: 8%; left: 24%; color: #776bff; animation-delay: -0.6s; }
.fc-hero-bubble-icon.i2 { bottom: 14%; left: 50%; transform: translateX(-50%); color: #6db4ff; animation-delay: -1.2s; }
.fc-hero-bubble-icon.i3 { top: 22%; right: 36%; color: #2f6bff; animation-delay: -2s; }
.fc-hero-bubble-icon.i4 { bottom: 25%; right: 11%; color: #22b25a; animation-delay: -3s; }

.fc-hero-float-card {
    position: absolute;
    border: 1px solid #d9e3f3;
    border-radius: 20px;
    background: #ffffff;
    box-shadow: 0 6px 18px rgba(20, 54, 120, 0.06);
    animation: fcFloat 7s ease-in-out infinite;
    color: #172b50;
    z-index: 2;
}

.fc-hero-card-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    font-size: 0.95rem;
    font-weight: 800;
    margin-bottom: 12px;
}

.fc-hero-chat-card {
    top: 10%;
    left: 2%;
    width: 250px;
    padding: 16px;
    animation-delay: -0.8s;
}

.fc-hero-msg {
    display: grid;
    grid-template-columns: 28px 1fr;
    gap: 9px;
    margin: 10px 0;
}

.fc-hero-avatar {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: block;
    object-fit: cover;
    border: 1px solid #d7e2f3;
}

.fc-hero-bubble {
    padding: 10px 12px;
    border-radius: 14px;
    background: rgba(247, 250, 255, 0.95);
    font-size: 0.77rem;
    line-height: 1.35;
    color: #233a62;
}

.fc-hero-chat-input {
    margin-top: 8px;
    height: 34px;
    border-radius: 10px;
    border: 1px solid #d8e2f2;
    background: rgba(255, 255, 255, 0.84);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 10px;
    color: #8b9bb8;
    font-size: 0.74rem;
}

.fc-hero-chat-input i {
    color: #2f6bff;
    font-size: 0.76rem;
}

.fc-hero-video-card {
    top: 7%;
    right: 2%;
    width: 300px;
    height: 196px;
    padding: 0;
    overflow: hidden;
    opacity: 1;
    animation-delay: -1.4s;
}

.fc-hero-video-bg {
    width: 100%;
    height: 100%;
    background:
        linear-gradient(90deg, rgba(16, 32, 66, 0.28), rgba(16, 32, 66, 0.06)),
        url("../images/home/hero-student-photo.93b30f8cfd75.png") center/cover no-repeat;
    position: relative;
}

.fc-hero-video-bg::after {
    content: "";
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0.18);
    pointer-events: none;
}

.fc-hero-controls {
    position: absolute;
    left: 50%;
    bottom: 12px;
    transform: translateX(-50%);
    display: flex;
    gap: 6px;
    padding: 6px;
    border-radius: 14px;
    background: rgba(11, 16, 30, 0.68);
}

.fc-hero-controls span {
    width: 28px;
    height: 28px;
    border-radius: 9px;
    background: rgba(255, 255, 255, 0.14);
    display: grid;
    place-items: center;
    color: #fff;
    font-size: 0.72rem;
}

.fc-hero-controls span.is-end {
    background: #ff4f5e;
}

.fc-hero-task-card {
    left: 3%;
    bottom: 11%;
    width: 246px;
    padding: 16px;
    animation-delay: -3.1s;
}

.fc-hero-english-task {
    margin-top: 8px;
    padding: 12px;
    border-radius: 12px;
    background: rgba(247, 250, 255, 0.84);
    color: #405274;
    line-height: 1.8;
    font-size: 0.72rem;
}

.fc-hero-sentence {
    margin-bottom: 8px;
    line-height: 1.45;
}

.fc-hero-gap {
    display: inline-flex;
    align-items: center;
    padding: 1px 6px;
    border-radius: 7px;
    background: #e8f7ef;
    border: 1px solid #bde9d1;
    color: #10874d;
    font-weight: 700;
}

.fc-hero-gap.is-empty {
    background: #eef3fd;
    border-color: #d4e1f7;
    color: #4c6590;
}

.fc-hero-word-bank {
    margin-top: 8px;
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.fc-hero-word-bank span {
    border-radius: 999px;
    border: 1px solid #d6e1f5;
    background: #fff;
    padding: 3px 8px;
    color: #37527c;
    font-size: 0.66rem;
    font-weight: 700;
}

.fc-hero-progress-card {
    right: 4%;
    left: auto;
    bottom: 2%;
    width: 282px;
    padding: 16px;
    display: grid;
    grid-template-columns: 84px 1fr;
    grid-template-rows: auto 1fr;
    align-items: start;
    gap: 12px;
    border-radius: 16px;
    animation-delay: -1s;
}

.fc-hero-progress-title {
    grid-column: 1 / -1;
    grid-row: 1;
    margin-bottom: 8px;
    font-size: 0.9rem;
    line-height: 1.2;
}

.fc-hero-progress-left {
    grid-column: 1;
    grid-row: 2;
}

.fc-hero-progress-right {
    grid-column: 2;
    grid-row: 2;
}

.fc-hero-ring {
    width: 84px;
    height: 84px;
    border-radius: 50%;
    background:
        radial-gradient(circle at center, #ffffff 0 62%, transparent 63% 100%),
        conic-gradient(#39c96b 0 78%, #e9eff8 78% 100%);
    display: grid;
    place-items: center;
    font-size: 1.05rem;
    font-weight: 900;
    color: #25af58;
}

.fc-hero-bars {
    display: flex;
    align-items: end;
    gap: 9px;
    height: 64px;
    margin-top: 2px;
}

.fc-hero-bar-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-end;
    height: 100%;
    gap: 2px;
}

.fc-hero-bar {
    display: block;
    width: 8px;
    height: var(--h, 60%);
    min-height: 8px;
    border-radius: 999px;
    background: linear-gradient(180deg, #93e7ae, #31c86a);
    opacity: 0.95;
}

.fc-hero-bar-item em {
    width: 18px;
    height: 18px;
    flex: 0 0 18px;
    box-sizing: border-box;
    border-radius: 999px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: #f0f4fb;
    border: 1px solid #d8e2f3;
    color: #334d79;
    font-style: normal;
    font-size: 0.58rem;
    line-height: 1;
    font-weight: 800;
    margin-top: 0;
}

.fc-hero-bar-item:nth-child(1) em { background: #e8f0ff; border-color: #cfdcff; color: #35528a; }
.fc-hero-bar-item:nth-child(2) em { background: #efe9ff; border-color: #dacfff; color: #5a4a9a; }
.fc-hero-bar-item:nth-child(3) em { background: #e8f8ef; border-color: #c9edd8; color: #2f7a55; }
.fc-hero-bar-item:nth-child(4) em { background: #fff2e6; border-color: #ffd9b8; color: #9a5f2c; }
.fc-hero-bar-item:nth-child(5) em { background: #eaf7ff; border-color: #ccecff; color: #2c6f96; }

@keyframes fcFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

@keyframes fcDrift {
    0%, 100% { transform: translate3d(0, 0, 0) scale(1); opacity: 0.6; }
    50% { transform: translate3d(18px, -24px, 0) scale(1.25); opacity: 1; }
}

.fc-landing-hero.fc-section {
    padding: 0;
}

    .fc-hero-note {
        margin-top: 0.95rem;
        font-size: 0.98rem;
        color: var(--fc-text-soft);
    }

    .fc-hero-media-wrap { position: relative; }

    .fc-screen {
        display: block;
        width: 100%;
        background: #fff;
        border: 1px solid var(--fc-border);
        border-radius: 18px;
        box-shadow: 0 12px 24px rgba(18, 43, 92, 0.08);
        overflow: hidden;
        text-decoration: none;
    }

    .fc-screen-clickable {
        transition: transform .2s ease, box-shadow .2s ease;
        cursor: pointer;
        position: relative;
    }

    .fc-screen-clickable:hover {
        transform: translateY(-2px);
        box-shadow: 0 24px 40px rgba(24, 52, 109, 0.16);
    }

    .fc-screen-live-chip {
        position: absolute;
        top: 12px;
        right: 14px;
        z-index: 2;
        background: #eaf8ef;
        color: #15803d;
        border: 1px solid #cdeedc;
        border-radius: 999px;
        padding: 0.24rem .55rem;
        font-size: .78rem;
        font-weight: 700;
    }

    .fc-screen-topbar {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 1rem;
        border-bottom: 1px solid #edf2fb;
        padding: 0.9rem 1rem;
        font-size: 0.9rem;
        color: var(--fc-text-soft);
        background: #fff;
    }

    .fc-screen-title {
        font-weight: 700;
        color: var(--fc-text);
    }

    .fc-screen-body { padding: 1rem; background: #f8fbff; }

    .fc-lesson-layout {
        display: grid;
        grid-template-columns: 58px 1fr 176px;
        gap: 1rem;
        align-items: stretch;
    }

    .fc-toolbar {
        background: #fff;
        border: 1px solid #e7eefb;
        border-radius: 16px;
        padding: 0.75rem 0.45rem;
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: 0.55rem;
    }

    .fc-tool {
        width: 34px;
        height: 34px;
        border-radius: 10px;
        color: var(--fc-text-soft);
        display: inline-flex;
        align-items: center;
        justify-content: center;
        background: #f6f8fd;
        font-size: .95rem;
    }

    .fc-tool.is-active { color: var(--fc-blue); background: #edf3ff; }

    .fc-tool-dot { width: 14px; height: 14px; border-radius: 999px; }
    .fc-tool-dot.black { background: #111827; }
    .fc-tool-dot.red { background: #ef4444; }
    .fc-tool-dot.blue { background: #2d6cff; }

    .fc-task-panel {
        background: #fff;
        border: 1px solid #e7eefb;
        border-radius: 16px;
        padding: 0.92rem;
        display: flex;
        flex-direction: column;
        gap: .85rem;
    }

    .fc-task-title { font-weight: 700; color: var(--fc-text); margin-bottom: 0; }

    .fc-task-image {
        width: 100%;
        border-radius: 14px;
        border: 1px solid #e7eefb;
        background: #f4f7fd;
        aspect-ratio: 16 / 9;
        object-fit: cover;
    }

    .fc-answer-list { display: flex; flex-direction: column; gap: .6rem; font-size: .98rem; color: #2d3748; }
    .fc-answer-line { display: flex; gap: 0.42rem; flex-wrap: wrap; align-items: center; }
    .fc-answer-fill { color: var(--fc-blue); font-weight: 700; font-style: italic; }

    .fc-gap-input {
        min-width: 96px;
        padding: 0.1rem 0.4rem;
        border-radius: 8px;
        border: 1px solid #cfdcf3;
        background: #fff;
        font-weight: 600;
        color: #1f2f48;
        outline: none;
        transition: border-color .15s ease, box-shadow .15s ease, background-color .15s ease;
    }

    .fc-gap-input:focus {
        border-color: #7ea2ea;
        box-shadow: 0 0 0 0.18rem rgba(37, 99, 235, 0.15);
    }

    .fc-gap-input.is-correct {
        border-color: #23a55a;
        background: #edf9f2;
        color: #166534;
    }

    .fc-gap-input.is-wrong {
        border-color: #e05555;
        background: #fff2f2;
        color: #991b1b;
    }

    .fc-side-panel { display: flex; flex-direction: column; gap: 0.62rem; }

    .fc-user-box, .fc-chat-box {
        background: #fff;
        border: 1px solid #e7eefb;
        border-radius: 12px;
        padding: .62rem;
    }

    .fc-user-label, .fc-chat-label {
        font-size: .78rem;
        font-weight: 700;
        color: var(--fc-text);
        margin-bottom: .38rem;
    }

    .fc-user-thumb {
        width: 100%;
        border-radius: 12px;
        aspect-ratio: 16/10;
        object-fit: cover;
        background: #f4f7fd;
    }

    .fc-chat-bubble {
        border-radius: 10px;
        padding: .35rem .48rem;
        font-size: .78rem;
        background: #f4f7fd;
        color: var(--fc-text);
        margin-bottom: .36rem;
    }

    .fc-chat-input {
        border: 1px solid #edf2fb;
        border-radius: 10px;
        background: #fbfcff;
        color: #9aa8c7;
        font-size: .78rem;
        padding: .5rem .6rem;
    }

    .fc-screen-hint {
        margin-top: .62rem;
        font-size: .88rem;
        color: #5c6f92;
        font-weight: 600;
    }

    .fc-section-title {
        font-size: clamp(1.8rem, 2.5vw, 2.45rem);
        font-weight: 800;
        line-height: 1.15;
        letter-spacing: 0;
        text-align: center;
        margin: 0 auto 1.8rem;
        max-width: 760px;
        color: #122b5c;
    }

    .fc-compare-card {
        height: 100%;
        padding: 24px;
        position: relative;
        overflow: hidden;
        transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
    }
    .fc-compare-card:hover {
        transform: translateY(-3px);
        box-shadow: 0 18px 44px rgba(20, 54, 120, 0.085);
    }
    .fc-compare-card.bad { background: #fffefe; border-color: #eadce0; }
    .fc-compare-card.good { background: #fbfffd; border-color: #d6eddf; position: relative; overflow: visible; }

    .fc-compare-title { display:flex; align-items:center; gap:.7rem; font-weight:800; font-size:1.3rem; margin-bottom:1rem; }
    .fc-compare-icon { width:34px; height:34px; border-radius:12px; display:inline-flex; align-items:center; justify-content:center; }
    .fc-compare-icon.bad { color: var(--fc-red); background: var(--fc-red-soft); }
    .fc-compare-icon.good { color: var(--fc-green); background: var(--fc-green-soft); }
    .fc-compare-book-image {
        position: absolute;
        top: -58px;
        right: -6px;
        width: min(186px, 40%);
        height: auto;
        z-index: 2;
        pointer-events: none;
        user-select: none;
    }

    .fc-chaos { display:grid; grid-template-columns:repeat(2,1fr); gap:11px; margin-bottom:1rem; }
    .fc-chaos-window { background:#fff; border:1px solid #e7eefb; border-radius:12px; padding:.62rem; min-height:106px; box-shadow:none; }
    .fc-chaos-bar { display:flex; gap:5px; margin-bottom:.5rem; }
    .fc-chaos-dot { width:8px; height:8px; border-radius:999px; background:#d8e1f2; }
    .fc-chaos-window-title { font-size:.76rem; font-weight:700; color:var(--fc-text); margin-bottom:.46rem; }
    .fc-chaos-video-grid { display:grid; grid-template-columns:repeat(2,1fr); gap:6px; }
    .fc-chaos-video-cell, .fc-chaos-pdf-icon, .fc-chaos-chat-line, .fc-chaos-board { background:#eff4fb; border-radius:10px; }
    .fc-chaos-video-cell { min-height:34px; }
    .fc-chaos-pdf-icon { min-height:52px; display:flex; align-items:center; justify-content:center; color:#dd4b39; font-size:1.25rem; }
    .fc-chaos-board {
        min-height: 52px;
        background: #f8fbff;
        border: 1px dashed #d8e3f6;
        position: relative;
    }

    .fc-chaos-board::before,
    .fc-chaos-board::after {
        content: none !important;
        display: none !important;
    }
    .fc-chaos-chat-line { height:12px; margin-bottom:8px; }

    .fc-list { list-style:none; padding-left:0; margin:0; display:flex; flex-direction:column; gap:.8rem; }
    .fc-list li { display:flex; align-items:flex-start; gap:.65rem; font-size:1rem; }
    .fc-list-mark { width:22px; height:22px; border-radius:8px; display:inline-flex; align-items:center; justify-content:center; font-size:.74rem; margin-top:1px; }
    .fc-list-mark.bad { background:#ffe7e7; color:var(--fc-red); }
    .fc-list-mark.good { background:#e8f8ef; color:var(--fc-green); }

    .fc-mini-screen { background:#fff; border:1px solid #e7eefb; border-radius:14px; padding:.66rem; overflow:hidden; box-shadow:none; margin-bottom:1rem; }
    .fc-mini-screen img { width:100%; border-radius:12px; display:block; aspect-ratio:16/9.6; object-fit:cover; background:#f4f7fd; }

    .fc-example-card {
        height:100%;
        padding:18px;
        overflow: hidden;
        transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
    }
    .js-lesson-preview-card {
        cursor: zoom-in;
    }
    .js-lesson-preview-card:hover {
        transform: translateY(-4px);
        border-color: #cddcf3;
        box-shadow: 0 18px 42px rgba(17, 39, 79, 0.11);
    }
    .fc-example-badge { display:inline-flex; align-items:center; min-height:28px; padding:0 .7rem; border-radius:999px; font-size:.82rem; font-weight:700; margin-bottom:.86rem; }
    .fc-example-badge.blue { color:#4f67d6; background:#edf0ff; }
    .fc-example-badge.green { color:#2d8b57; background:#eaf7ef; }
    .fc-example-badge.indigo { color:#5860d8; background:#eef0ff; }
    .fc-example-title { font-size:1.5rem; font-weight:800; line-height:1.2; margin-bottom:.32rem; }
    .fc-example-count { color:var(--fc-text-soft); margin-bottom:1rem; }
    .fc-example-preview {
        width:100%;
        border-radius:14px;
        border:1px solid #e7eefb;
        background:#f4f7fd;
        transition: transform .2s ease;
    }
    .js-lesson-preview-card:hover .fc-example-preview {
        transform: scale(1.02);
    }

    .fc-feature-card {
        height:100%;
        padding:24px;
        transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
    }
    .fc-feature-card:hover {
        border-color: #cddcf3;
        box-shadow: 0 18px 42px rgba(17, 39, 79, 0.1);
    }
    .fc-feature-icon { width:52px; height:52px; border-radius:16px; display:inline-flex; align-items:center; justify-content:center; font-size:1.45rem; margin-bottom:1rem; }
    .fc-feature-icon.purple { color:#6554d9; background:#eef0ff; }
    .fc-feature-icon.green { color:#15803d; background:#edf9f2; }
    .fc-feature-icon.blue { color:#2563eb; background:#edf3ff; }
    .fc-feature-title { font-size:1.3rem; font-weight:800; line-height:1.25; margin-bottom:.55rem; }
    .fc-feature-text { color:var(--fc-text-soft); font-size:1rem; line-height:1.5; margin-bottom:0; }

    .fc-cta {
        padding:30px 32px;
        background:#ffffff;
        position:relative;
        overflow: hidden;
    }
    .fc-cta::before {
        content: "";
        position: absolute;
        inset: auto -12% -70% -12%;
        height: 120%;
        background-image:
            linear-gradient(rgba(73, 125, 215, 0.045) 1px, transparent 1px),
            linear-gradient(90deg, rgba(73, 125, 215, 0.045) 1px, transparent 1px);
        background-size: 54px 54px;
        transform: perspective(560px) rotateX(58deg);
        transform-origin: bottom;
        pointer-events: none;
    }
    .fc-cta > * {
        position: relative;
        z-index: 1;
    }
    .fc-cta-title { font-size:clamp(2rem,3vw,3rem); line-height:1.08; font-weight:800; margin-bottom:.45rem; }
    .fc-cta-text { color:var(--fc-text-soft); font-size:1.12rem; margin-bottom:0; }
    .fc-cta-note { margin-top:.8rem; color:var(--fc-text-soft); font-size:.95rem; text-align:center; }

    .lesson-preview-overlay {
        position: fixed;
        inset: 0;
        z-index: 1080;
        background: rgba(8, 14, 28, 0.82);
        display: flex;
        align-items: center;
        justify-content: center;
        padding: 22px;
    }

    .lesson-preview-overlay img {
        max-width: min(1100px, 94vw);
        max-height: 88vh;
        border-radius: 14px;
        box-shadow: 0 24px 60px rgba(0, 0, 0, 0.34);
        object-fit: contain;
        background: #fff;
    }

    .lesson-preview-close {
        position: absolute;
        top: 16px;
        right: 16px;
        width: 42px;
        height: 42px;
        border-radius: 50%;
        border: 0;
        display: inline-flex;
        align-items: center;
        justify-content: center;
        font-size: 1.1rem;
        color: #fff;
        background: rgba(255, 255, 255, 0.18);
    }

    body.lesson-preview-open {
        overflow: hidden;
    }

    @media (max-width: 991.98px) {
        .fc-section { padding: 34px 0; }
        .fc-hero { padding: 22px; }
        .fc-lesson-layout { grid-template-columns: 1fr; }
        .fc-toolbar { flex-direction: row; justify-content: center; flex-wrap: wrap; }
        .fc-side-panel { display:grid; grid-template-columns:1fr; }
        .fc-compare-book-image {
            top: -52px;
            right: -4px;
            width: min(156px, 39%);
        }
    }

    @media (max-width: 767.98px) {
        .fc-primary-btn { width:100%; justify-content:center; }
        .fc-card, .fc-hero, .fc-compare-card, .fc-feature-card, .fc-example-card, .fc-cta { border-radius: 20px; }
        .fc-hero-title { font-size:2.2rem; }
        .fc-compare-card, .fc-feature-card, .fc-example-card { padding:18px; }
        .fc-cta { padding:22px 18px; text-align:center; }
        .fc-section-title {
            text-align:left;
            font-size:1.72rem;
            margin:0 0 1.1rem;
            max-width: 100%;
        }
        .fc-compare-book-image {
            top: -38px;
            right: -2px;
            width: min(128px, 40%);
        }
    }

.hero-class-preview {
    width: 100%;
    margin: 0 auto;
    background: #ffffff;
    border-radius: 24px !important;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.hero-class-preview:hover {
    transform: translateY(-2px);
    box-shadow: 0 0.9rem 2.2rem rgba(22, 34, 66, 0.1) !important;
}

.hero-class-preview--compact {
    max-width: 760px;
    margin-left: auto;
    display: none;
}

.hero-class-preview--compact .hero-logo {
    width: 46px;
    height: 46px;
    border-radius: 14px;
    font-size: 25px;
}

.hero-class-preview--compact .hero-title {
    font-size: 24px;
}

.hero-class-preview--compact .hero-subtitle {
    font-size: 14px;
}

.hero-class-preview--compact .status-pill,
.hero-class-preview--compact .user-pill {
    display: none;
}

.hero-class-preview--compact .lesson-card,
.hero-class-preview--compact .chat-card {
    padding: 16px;
    border-radius: 18px;
}

.hero-class-preview--compact .lesson-title {
    font-size: 18px;
    margin-bottom: 1rem !important;
}

.hero-class-preview--compact .task-image {
    border-radius: 14px;
    margin-bottom: 1rem !important;
}

.hero-class-preview--compact .task-list {
    gap: 10px;
    font-size: 16px;
}

.hero-class-preview--compact .task-input {
    width: 126px;
    height: 38px;
    border-radius: 10px;
    font-size: 15px;
}

.hero-class-preview--compact .word-bank {
    border-radius: 14px;
    padding: 12px;
    margin-top: 1rem !important;
}

.hero-class-preview--compact .word-bank-title {
    font-size: 14px;
    margin-bottom: .7rem !important;
}

.hero-class-preview--compact .word-badge {
    min-width: 96px;
    height: 38px;
    border-radius: 10px;
    font-size: 14px;
}

.hero-class-preview--compact .side-title {
    font-size: 18px;
    margin-bottom: .8rem !important;
}

.hero-class-preview--compact .chat-card {
    height: 230px;
}

.hero-class-preview--compact .chat-message {
    min-height: 48px;
    padding: 10px 12px;
    font-size: 14px;
}

.hero-class-preview--compact .chat-message small,
.hero-class-preview--compact .chat-form,
.hero-class-preview--compact .video-card {
    display: none;
}

    .hero-logo {
        width: 58px;
        height: 58px;
        border-radius: 18px;
        background: #18b968;
        color: #ffffff;
        display: grid;
        place-items: center;
        font-size: 32px;
        font-weight: 800;
    }

    .hero-title,
    .lesson-title,
    .side-title {
        color: #102754;
        font-weight: 800;
    }

    .hero-title {
        font-size: 30px;
    }

.hero-subtitle {
    color: #7d8fb3;
    font-size: 18px;
    font-weight: 500;
}

.hero-top-note {
    border: 1px solid #dce6f6;
    background: #f7fbff;
    border-radius: 16px;
    padding: 10px 14px;
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.hero-top-note-icon {
    width: 20px;
    height: 20px;
    flex: 0 0 auto;
}

.hero-top-note-text {
    color: #4f6287;
    font-size: 16px;
    font-weight: 600;
    line-height: 1.4;
}

.hero-top-note-accent {
    color: #1d4ed8;
    background: #e9f1ff;
    border-radius: 8px;
    padding: 1px 6px;
    font-weight: 700;
    white-space: nowrap;
}

    .status-pill,
    .user-pill {
        height: 48px;
        border-radius: 999px;
        display: inline-flex;
        align-items: center;
        gap: 10px;
        padding: 0 20px;
        font-size: 18px;
        font-weight: 700;
    }

    .status-pill {
        color: #11914b;
        background: #e6f8ec;
    }

    .status-pill span {
        width: 12px;
        height: 12px;
        border-radius: 50%;
        background: #12b857;
    }

    .user-pill {
        border: 1px solid #dce7f8;
        background: #ffffff;
        color: #102754;
        pointer-events: none;
        cursor: default;
    }

.lesson-card,
.chat-card,
.video-card {
    border: 1px solid #dfe9f8;
    border-radius: 24px;
    background: #ffffff;
}

.lesson-card {
    padding: 24px;
}

.lesson-title {
    font-size: 24px;
    line-height: 1.3;
}

.task-image {
    width: 100%;
    border-radius: 18px;
    object-fit: cover;
    aspect-ratio: 16 / 8;
}

.task-list {
    display: grid;
    gap: 18px;
    font-size: 21px;
    color: #25324a;
}

    .task-row {
        display: flex;
        flex-wrap: wrap;
        align-items: center;
        gap: 10px 12px;
    }

.task-match-row {
    display: grid;
    grid-template-columns: minmax(130px, 200px) minmax(220px, 1fr);
    gap: 12px;
    align-items: center;
}

.task-match-label {
    font-size: 19px;
    font-weight: 700;
    color: #1f355d;
}

.task-input {
    width: 170px;
    height: 48px;
    border: 1.5px solid #d9e4f5;
    border-radius: 14px;
    padding: 0 14px;
    font-size: 18px;
    outline: none;
    transition: border-color 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

    .task-input:focus {
        border-color: #7aa7ff;
        box-shadow: 0 0 0 4px rgba(60, 121, 255, 0.1);
    }

.task-drop {
    min-height: 52px;
    border: 1.5px dashed #c3d4f3;
    border-radius: 14px;
    background: #f8fbff;
    padding: 10px 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: border-color 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

.task-drop-value {
    font-size: 18px;
    font-weight: 600;
    color: #1c345d;
}

.task-drop-placeholder {
    color: #8ca1c6;
    font-size: 16px;
    font-weight: 600;
}

.task-target.is-valid {
    border-color: #19a75a;
    background: #effaf3;
    color: #128044;
}

.task-target.is-invalid {
    border-color: #ef4444;
    background: #fff1f1;
}

.word-bank {
    border: 1px solid #dfeee5;
    border-radius: 18px;
    background: #fbfdfb;
    padding: 16px 18px;
}

.word-bank-title {
    color: #1e2a44;
    font-size: 18px;
    font-weight: 800;
}

.word-badge {
    min-width: 120px;
    height: 46px;
    border: 1.5px solid #d5e1f2;
    border-radius: 12px;
    background: #ffffff;
    color: #1f2d44;
    font-size: 17px;
    font-weight: 600;
    transition: opacity 0.15s ease, text-decoration-color 0.15s ease, transform 0.15s ease, box-shadow 0.15s ease;
    cursor: grab;
    touch-action: none;
    -webkit-user-select: none;
    user-select: none;
}

.word-badge:active {
    cursor: grabbing;
}

.word-badge.is-dragging {
    opacity: 0.65;
    transform: scale(0.98);
}

.touch-drag-ghost {
    position: fixed;
    z-index: 9999;
    pointer-events: none;
    transform: translate(-50%, -50%) translate3d(0, 0, 0);
    background: #ffffff;
    border: 1.5px solid #d5e1f2;
    border-radius: 12px;
    min-height: 42px;
    padding: 8px 12px;
    box-shadow: 0 12px 24px rgba(17, 39, 82, 0.22);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    max-width: min(78vw, 360px);
}

.touch-drag-ghost-content {
    color: #1f2d44;
    font-size: 16px;
    font-weight: 600;
    line-height: 1.2;
    white-space: nowrap;
}

.task-target.is-drag-over {
    border-color: #4f86f7;
    box-shadow: 0 0 0 4px rgba(79, 134, 247, 0.16);
}

    .word-badge.used {
        opacity: 0.45;
        text-decoration: line-through;
    }

.side-column {
    display: grid;
    gap: 14px;
    grid-auto-rows: max-content;
    align-content: start;
    align-items: start;
}

.chat-card {
    height: 340px;
    padding: 20px;
    display: flex;
    flex-direction: column;
}

.side-title {
    font-size: 22px;
}

.chat-messages {
    display: flex;
    flex-direction: column;
    gap: 10px;
    flex: 1 1 auto;
    min-height: 0;
    overflow-y: hidden;
    padding-right: 4px;
}

.chat-message {
    min-height: 62px;
    border-radius: 14px;
    background: #f4f6fb;
    color: #15233d;
    padding: 14px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    font-size: 16px;
}

    .chat-message small {
        color: #8b97ab;
        font-size: 14px;
        white-space: nowrap;
    }

.chat-form {
    height: 50px;
    border: 1.5px solid #dce6f5;
    border-radius: 14px;
    display: flex;
    flex: 0 0 auto;
    align-items: center;
    padding: 0 8px 0 14px;
}

.chat-form input {
    flex: 1;
    border: 0;
    outline: 0;
    min-width: 120px;
    font-size: 16px;
    color: #16233d;
}

    .chat-form input::placeholder {
        color: #9aa9c5;
    }

.chat-form button {
    width: 36px;
    height: 36px;
    border: 0;
    border-radius: 10px;
    background: #eef5ff;
    color: #2458d3;
    font-size: 16px;
}

.chat-form--decorative {
    pointer-events: none;
}

.chat-form--decorative input,
.chat-form--decorative button {
    pointer-events: none;
    cursor: default;
}

.video-card {
    overflow: hidden;
    width: 100%;
}

    .student-video {
        width: 100%;
        aspect-ratio: 16 / 9;
        object-fit: cover;
        display: block;
    }

.call-panel {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    padding: 6px 12px;
    background: #ffffff;
}

.call-panel button {
    width: 34px;
    height: 34px;
    border-radius: 10px;
    border: 0;
    background: transparent;
    color: #109456;
    font-size: 18px;
    line-height: 1;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
    cursor: default;
}

    .call-panel .call-end {
        color: #ef3f4a;
    }

    .call-panel .bi-display {
        color: #202838;
    }

@media (max-width: 991.98px) {
    .fc-landing-hero {
        min-height: 920px;
        height: 920px;
    }

    .fc-landing-hero-copy {
        max-width: 640px;
    }

    .fc-landing-hero-actions {
        justify-content: center;
    }

    .fc-hero-float-card {
        opacity: 0.8;
    }

    .fc-hero-video-card {
        opacity: 1;
    }

    .fc-hero-bubble-icon.i1,
    .fc-hero-bubble-icon.i3 {
        display: none;
    }

    .fc-hero-chat-card {
        top: 4%;
        left: 2%;
    }

    .fc-hero-video-card {
        top: 3%;
        right: 2%;
    }

    .fc-hero-task-card {
        bottom: 2%;
        left: 3%;
    }

    .fc-hero-progress-card {
        right: 4%;
        left: auto;
        bottom: 2%;
        width: 276px;
        transform: scale(0.9);
    }

    .hero-class-preview {
        border-radius: 22px !important;
        padding: 20px !important;
    }

    .lesson-card,
    .chat-card {
        padding: 18px;
    }

    .task-list {
        font-size: 19px;
    }

    .task-input {
        width: 150px;
    }

    .task-match-row {
        grid-template-columns: minmax(120px, 160px) minmax(200px, 1fr);
    }
}

@media (max-width: 767.98px) {
    .fc-landing-hero {
        flex-direction: column;
        justify-content: flex-start;
        padding-left: 0;
        padding-right: 0;
        min-height: 1040px;
        height: 1040px;
    }

    .fc-landing-hero-copy {
        order: 1;
        padding-left: 14px;
        padding-right: 14px;
        z-index: 6;
        margin-top: 370px;
    }

    .fc-landing-hero-title {
        font-size: 1.72rem;
    }

    .fc-landing-hero-text {
        font-size: 0.9rem;
        line-height: 1.42;
    }

    .fc-landing-hero-actions {
        flex-direction: column;
        align-items: stretch;
    }

    .fc-secondary-btn,
    .fc-landing-hero-actions .fc-primary-btn {
        width: 100%;
        justify-content: center;
    }

    .fc-hero-mobile-features {
        display: none;
    }

    .fc-hero-bubble-icon {
        display: none;
    }

    .fc-hero-particle.p2 {
        top: 27%;
    }

    .fc-hero-chat-card {
        top: 5%;
        left: 2%;
        transform: scale(0.76);
    }

    .fc-hero-video-card {
        top: 2%;
        left: auto;
        right: -16%;
        transform: scale(0.72);
    }

    .fc-hero-task-card {
        bottom: 10%;
        left: 2%;
        transform: scale(0.72);
    }

    .fc-hero-progress-card {
        top: auto;
        bottom: 14%;
        right: -18%;
        left: auto;
        width: 286px;
        transform: scale(0.69);
    }

    .fc-hero-video-card {
        opacity: 1;
    }

    .task-drop-value {
        font-size: 15px;
    }

    .word-bank-title {
        font-size: 15px;
    }

    .word-badge {
        min-width: 98px;
        height: 38px;
        font-size: 14px;
        border-radius: 9px;
    }

    .side-title {
        font-size: 18px;
    }

    .chat-card {
        height: 280px;
    }

    .chat-message {
        min-height: 50px;
        font-size: 14px;
        padding: 10px 12px;
    }

    .chat-message small {
        font-size: 12px;
    }

    .chat-form {
        height: 44px;
        border-radius: 12px;
        padding: 0 6px 0 10px;
    }

    .chat-form input {
        font-size: 14px;
    }

    .chat-form button {
        width: 32px;
        height: 32px;
        font-size: 14px;
    }

    .call-panel {
        gap: 10px;
        padding: 6px 10px;
    }

    .call-panel button {
        width: 30px;
        height: 30px;
        font-size: 17px;
        border-radius: 8px;
    }
}

@media (max-width: 575.98px) {
    .fc-landing-hero-title {
        font-size: 1.48rem;
    }

    .fc-landing-hero-text {
        font-size: 0.84rem;
    }

    .fc-hero-chat-card {
        left: 1%;
    }

    .fc-hero-video-card {
        left: auto;
        right: -18%;
    }

    .fc-hero-task-card {
        left: 1%;
    }

    .fc-hero-progress-card {
        top: auto;
        bottom: 5%;
        right: -14%;
        left: auto;
        width: 268px;
        transform: scale(0.64);
    }
}

@media (min-width: 430px) and (max-width: 767.98px) {
    .fc-hero-mobile-features {
        gap: 12px;
    }

    .fc-hero-mobile-feature {
        font-size: 0.76rem;
    }

    .fc-hero-mobile-feature i {
        width: 46px;
        height: 46px;
        font-size: 1.22rem;
        border-radius: 13px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .fc-hero-float-card {
        animation: none;
        transform: none !important;
    }
}