* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    background: #f4f5f4;
    color: #123b2c;
}


/* =========================================================
   HEADER
   ========================================================= */

.kt-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: #005b3c;
    color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
}

.kt-header-inner {
    max-width: 1400px;
    margin: auto;
    padding: 14px 24px;

    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.kt-header-title {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 0.5px;
}

.kt-header-actions {
    display: flex;
    gap: 10px;
}

.kt-btn {
    border: none;
    border-radius: 7px;
    padding: 10px 16px;

    font-size: 14px;
    font-weight: 700;

    cursor: pointer;

    transition:
        transform 0.15s ease,
        opacity 0.15s ease;
}

.kt-btn:hover {
    transform: translateY(-1px);
    opacity: 0.9;
}

.kt-btn-back {
    background: white;
    color: #005b3c;
}

.kt-btn-index {
    background: #f0a500;
    color: white;
}


/* =========================================================
   MAIN
   ========================================================= */

.kt-main {
    max-width: 1400px;
    margin: auto;
    padding: 30px 24px 50px;
}

.kt-title-area {
    margin-bottom: 25px;
}

.kt-title-area h1 {
    margin: 0 0 8px;
    color: #005b3c;
    font-size: 30px;
}

.kt-title-area p {
    margin: 0;
    color: #666;
    line-height: 1.6;
}

.kt-breadcrumb {
    color: #777;
    font-size: 14px;
    margin-bottom: 8px;
}


/* =========================================================
   LAYOUT UTAMA
   ========================================================= */

.kt-main-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 330px;
    gap: 25px;
    align-items: start;
}


/* =========================================================
   COVER BESAR
   ========================================================= */

.kt-feature {
    background: white;
    border-radius: 14px;
    padding: 20px;

    box-shadow:
        0 5px 20px rgba(0, 0, 0, 0.10);
}

.kt-feature-link {
    display: block;
    color: inherit;
    text-decoration: none;
}

.kt-feature-image-wrap {
    position: relative;

    width: 100%;
    height: 680px;

    display: flex;
    align-items: center;
    justify-content: center;

    overflow: hidden;

    background: #eeeeee;
    border-radius: 10px;
}

.kt-feature-image {
    width: 100%;
    height: 100%;
    object-fit: contain;

    transition:
        transform 0.25s ease;
}

.kt-feature-image-wrap:hover
.kt-feature-image {
    transform: scale(1.025);
}


/* =========================================================
   HOVER COVER UTAMA
   ========================================================= */

.kt-hover-overlay {
    position: absolute;
    inset: 0;

    display: flex;
    align-items: center;
    justify-content: center;

    background: rgba(0, 0, 0, 0.42);

    opacity: 0;

    transition:
        opacity 0.2s ease;

    pointer-events: none;
}

.kt-feature-image-wrap:hover
.kt-hover-overlay {
    opacity: 1;
}

.kt-hover-overlay span {
    background: #00733f;
    color: white;

    padding: 13px 25px;

    border-radius: 7px;

    font-weight: 700;

    box-shadow:
        0 4px 15px rgba(0, 0, 0, 0.25);
}

.kt-feature-info {
    padding: 18px 5px 5px;
}

.kt-feature-sheet {
    color: #00733f;
    font-size: 13px;
    font-weight: 700;

    text-transform: uppercase;

    margin-bottom: 7px;
}

.kt-feature-info h2 {
    margin: 0;
    font-size: 21px;
    line-height: 1.4;
}


/* =========================================================
   DAFTAR SHEET
   ========================================================= */

.kt-sheet-panel {
    background: white;
    border-radius: 14px;
    padding: 20px;

    box-shadow:
        0 5px 20px rgba(0, 0, 0, 0.10);
}

.kt-panel-title {
    font-size: 18px;
    font-weight: 700;
    color: #005b3c;

    border-bottom:
        2px solid #e5e5e5;

    padding-bottom: 12px;
    margin-bottom: 12px;
}

.kt-sheet-list {
    display: flex;
    flex-direction: column;
    gap: 9px;
}

.kt-sheet-button {
    width: 100%;

    border: 1px solid #dddddd;
    background: #fafafa;

    border-radius: 8px;

    padding: 10px;

    cursor: pointer;

    display: flex;
    align-items: center;

    gap: 12px;

    text-align: left;

    transition:
        background 0.15s ease,
        transform 0.15s ease;
}

.kt-sheet-button:hover {
    background: #edf7f1;
    transform: translateX(2px);
}

.kt-sheet-thumb {
    width: 42px;
    height: 58px;

    flex: 0 0 42px;

    object-fit: contain;

    background: white;

    border-radius: 4px;

    border: 1px solid #ddd;
}

.kt-sheet-name {
    font-size: 13px;
    font-weight: 700;

    color: #174b37;

    line-height: 1.3;
}

.kt-sheet-count {
    display: block;

    margin-top: 4px;

    color: #777;

    font-size: 11px;
    font-weight: normal;
}


/* =========================================================
   GRID BUKU
   ========================================================= */

.kt-book-grid {
    display: grid;

    grid-template-columns:
        repeat(
            auto-fill,
            minmax(190px, 1fr)
        );

    gap: 22px;
}

.kt-book-card {
    background: white;

    border-radius: 12px;

    overflow: hidden;

    box-shadow:
        0 4px 15px rgba(0, 0, 0, 0.09);

    transition:
        transform 0.2s ease,
        box-shadow 0.2s ease;
}

.kt-book-card:hover {
    transform: translateY(-4px);

    box-shadow:
        0 8px 22px rgba(0, 0, 0, 0.14);
}

.kt-book-link {
    display: block;

    color: inherit;

    text-decoration: none;
}

.kt-book-image-wrap {
    position: relative;

    height: 300px;

    background: #eeeeee;

    overflow: hidden;
}

.kt-book-image {
    width: 100%;
    height: 100%;

    object-fit: contain;

    transition:
        transform 0.2s ease;
}

.kt-book-card:hover
.kt-book-image {
    transform: scale(1.025);
}


/* =========================================================
   HOVER PDF BUKU
   ========================================================= */

.kt-book-hover {
    position: absolute;
    inset: 0;

    display: flex;
    align-items: center;
    justify-content: center;

    background:
        rgba(0, 0, 0, 0.40);

    opacity: 0;

    transition:
        opacity 0.2s ease;
}

.kt-book-card:hover
.kt-book-hover {
    opacity: 1;
}

.kt-book-hover span {
    background: #00733f;
    color: white;

    padding: 10px 18px;

    border-radius: 6px;

    font-size: 13px;
    font-weight: 700;
}


/* =========================================================
   INFO BUKU
   ========================================================= */

.kt-book-info {
    padding: 14px;
}

.kt-book-number {
    font-size: 11px;

    color: #00733f;

    font-weight: 700;

    margin-bottom: 6px;
}

.kt-book-title {
    font-size: 14px;

    line-height: 1.4;

    font-weight: 700;
}


/* =========================================================
   LOADING
   ========================================================= */

.kt-loading {
    text-align: center;

    padding: 50px;

    color: #666;

    font-weight: 700;
}


/* =========================================================
   ERROR
   ========================================================= */

.kt-error {
    background: white;

    border-radius: 12px;

    padding: 30px;

    text-align: center;

    color: #a00;
}

.kt-error h2 {
    margin-top: 0;
}


/* =========================================================
   HIDDEN
   ========================================================= */

.kt-hidden {
    display: none !important;
}


/* =========================================================
   FOOTER
   ========================================================= */

.kt-footer {
    text-align: center;

    padding: 25px;

    color: #777;

    font-size: 12px;
}


/* =========================================================
   RESPONSIVE
   ========================================================= */

@media (max-width: 900px) {

    .kt-main-layout {
        grid-template-columns: 1fr;
    }

    .kt-feature-image-wrap {
        height: 560px;
    }

    .kt-sheet-panel {
        order: 2;
    }

}


@media (max-width: 600px) {

    .kt-header-inner {
        flex-direction: column;
        align-items: stretch;
    }

    .kt-header-actions {
        width: 100%;
    }

    .kt-btn {
        flex: 1;
    }

    .kt-main {
        padding: 20px 14px 40px;
    }

    .kt-feature-image-wrap {
        height: 460px;
    }

    .kt-book-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    .kt-book-image-wrap {
        height: 230px;
    }

}