:root {
    --primary-green: #27ae60;
    --hover-green: #219150;
    --bg-grey: #f8f9fa;
    --border-grey: #dee2e6;
    --text-black: #000000;
}

.concrete-tool-wrapper {
    width: 100%;
    padding: 20px 0;
    font-family: 'Segoe UI', Arial, sans-serif;
}

.concrete-tool-wrapper .container {
    max-width: 900px;
    margin: 0 auto;
    background: #ffffff;
    padding: 30px;
    border-radius: 12px;
    border-top: 8px solid var(--primary-green);
    box-shadow: 0 5px 20px rgba(0,0,0,0.05);
}

.concrete-tool-wrapper .section-title {
    margin: 25px 0 15px 0;
    font-size: 18px;
    color: var(--text-black);
    font-weight: 700;
    text-transform: uppercase;
    border-left: 5px solid var(--primary-green);
    padding-left: 12px;
}

.concrete-tool-wrapper .grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 20px;
}

.concrete-tool-wrapper label {
    font-weight: 700;
    margin-bottom: 8px;
    display: block;
    color: #444;
}

.concrete-tool-wrapper select, 
.concrete-tool-wrapper input {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-grey);
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    color: var(--text-black);
    outline: none;
    box-sizing: border-box;
}

.concrete-tool-wrapper select:focus, 
.concrete-tool-wrapper input:focus {
    border-color: var(--primary-green);
}

.concrete-tool-wrapper .btn-calculate {
    background: var(--primary-green);
    color: white;
    padding: 18px;
    border: none;
    border-radius: 8px;
    font-size: 18px;
    font-weight: 700;
    cursor: pointer;
    width: 100%;
    transition: 0.3s;
    margin-top: 10px;
}

.concrete-tool-wrapper .btn-calculate:hover {
    background: var(--hover-green);
}

.concrete-tool-wrapper #results {
    margin-top: 30px;
    display: none;
}

.concrete-tool-wrapper .result-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 15px;
}

.concrete-tool-wrapper .result-card {
    padding: 20px;
    border: 2px solid var(--border-grey);
    border-radius: 10px;
    text-align: center;
}

.concrete-tool-wrapper .result-card.highlight {
    background: #f1fcf5;
    border-color: var(--primary-green);
}

.concrete-tool-wrapper .result-card p {
    font-size: 22px;
    font-weight: 800;
    color: var(--text-black);
    margin: 10px 0 0 0;
}

.concrete-tool-wrapper .estimation-box {
    margin-top: 30px;
    padding: 25px;
    border-radius: 12px;
    border: 1px solid var(--border-grey);
}

.concrete-tool-wrapper .manual-mix {
    background: #eef7f2;
    border-color: #c3e6cb;
}

.concrete-tool-wrapper .premix {
    background: var(--bg-grey);
}

.concrete-tool-wrapper .estimation-box h3 {
    margin: 0 0 15px 0;
    font-size: 18px;
    text-align: center;
    color: #333;
}

.concrete-tool-wrapper .material-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
}

.concrete-tool-wrapper .bag-box {
    background: white;
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border-grey);
    box-shadow: 0 2px 5px rgba(0,0,0,0.02);
}

.concrete-tool-wrapper .bag-box strong { display: block; color: #444; }

.concrete-tool-wrapper .bag-box span {
    display: block;
    font-size: 24px;
    font-weight: 800;
    color: var(--primary-green);
    margin: 5px 0;
}

.concrete-tool-wrapper .bag-box small {
    color: #888;
    font-weight: 600;
}

.concrete-tool-wrapper .note {
    font-size: 13px;
    color: #666;
    margin-top: 15px;
    text-align: center;
}

.concrete-tool-wrapper .shape-section { display: none; }