:root {
    --primary-bg: #f4f7fc;
    --card-bg: #ffffff;
    --text-color: #333;
    --header-color: #1a2b4e;
    --accent-color: #4a69bd;
    --accent-hover: #3b5496;
    --operator-color: #f6b93b;
    --function-color: #6a89cc;
    --equals-color: #38ada9;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --delete-matrix :rgb(255, 99, 71);
    --delete-matrix-hover:rgba(231, 68, 40, 0.945);
}
*{
    box-sizing: border-box;
    margin: 0px;
    padding: 0%;
}
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--primary-bg);
    color: var(--text-color);
    margin: 0 clamp(10px,5vw,40px);
    padding: 1rem;
}

.app-container {
    width:100%;
    max-width: 1400px;
    margin: auto;
}
header{
    display: flex;
    justify-content: center;
    align-items: center;
}
header h1 {
    display: inline;
    font-size: min(50px,calc(8vw + 1rem));
    font-weight: 800;
    text-align: center;
    margin-bottom: 2rem; 
    background: linear-gradient(90deg, #1a2b4e 0%, #4a69bd 100%);
    color: transparent;
    background-clip: text;

}

.card {
    background-color: var(--card-bg);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
}

.calculator-main {
    display: grid;
    grid-template-columns: 2fr 2.5fr; 
    grid-template-rows: auto 1fr;
    gap: 2rem;
    grid-template-areas:
        "stored     expression"
        "result     keypad";
}

.stored-matrices-panel { grid-area: stored; }
.result-panel          { grid-area: result; }
.expression-panel      { grid-area: expression; }
.keypad-panel          { grid-area: keypad; }


.expression-display {
    background-color: #e9ecef;
    border-radius: 8px;
    padding: 1rem;
    min-height: 40px;
    font-size: 1.5rem;
    font-weight: bold;
    text-align: right;
    word-wrap: break-word;
    margin-top: 1rem;
    border: 1px solid #ced4da;
}
.expression-display:focus {
    outline: 2px solid var(--accent-color);
}

.result-display {
    margin-top: 1rem;
    padding: 1rem;
    border: 1px dashed #ccc;
    border-radius: 8px;
    flex-grow: 1; 
    display: flex;
    align-items: center;
    justify-content: center;
    overflow-x: auto;
}

.matrix-grid-result {
    display: grid;
    gap: 5px;
    font-family: 'Courier New', Courier, monospace;
}

.matrix-grid-result span {
    font-size: 30px;
    font-weight: 700;
    border: 1px solid black;
    background-color: #f8f9fa;
    padding: 8px;
    text-align: center;
    border-radius: 4px;
    min-width: 40px;
}

.keypad {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
}

.keypad-btn {
    padding: 1rem;
    font-size: 1.2rem;
    font-weight: bold;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    background-color: #e9ecef;
}

.keypad-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.keypad-btn.operator { background-color: var(--operator-color); color: white; }
.keypad-btn.function { background-color: var(--function-color); color: white; }
.keypad-btn.equals { background-color: var(--equals-color); color: white; }
.keypad-btn.clear { background-color: #e74c3c; color: white; }

/* Stored Matrices */
.stored-matrices-list {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 1rem;
}
.stored-matrix-item  {
    display: flex;
    align-items: center;
    justify-content: center;
}
.stored-matrix-item {
    height: 40px;
    background-color: var(--accent-color);
    border-radius: 10px;
    color: white;
    overflow: hidden;
    font-weight: bold;
    transition: background-color 0.2s;
}
.stored-matrix-name{
    flex: 1;
    height: 100%;
    cursor: pointer;
    padding: 0px 10px;
    font-size: 25px;
}
.delete-matrix-btn{
    flex: 1;
    cursor:pointer;
    height: 100%;
    background-color: var(--delete-matrix);
    border: none;
    outline: none;
    padding: 0px 10px;
    font-size: 25px;
    font-weight: 700;
}
.stored-matrix-name:hover { background-color: var(--accent-hover); }
.delete-matrix-btn:hover { background-color: var(--delete-matrix-hover);}
.action-btn {
    display: block;
    width: 100%;
    padding: 12px;
    font-size: 1rem;
    font-weight: bold;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    background-color: var(--accent-color);
    color: white;
    margin-top: 1rem;
}
.action-btn:hover { background-color: var(--accent-hover); }

.info-box {
    margin-top: 1.5rem;
    padding: 1rem;
    background-color: #e9ecef;
    border-radius: 8px;
    font-size: 0.9rem;
    text-align: center;
}

.modal {
    display: none; position: fixed; z-index: 1000;
    left: 0; top: 0; width: 100%; height: 100%;
    background-color: rgba(0,0,0,0.5);
    align-items: center; justify-content: center;
}
.modal-content {
    background-color: var(--card-bg); padding: 2rem;
    border-radius: 12px; max-width: 90%; max-height: 90%;
    width: fit-content; position: relative;
    animation: fadeIn 0.3s; overflow-y: auto;
}
.close-btn {
    position: absolute; top: 10px; right: 20px;
    font-size: 2rem; font-weight: bold; cursor: pointer;
}
.editor-controls { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 1rem; }
.editor-controls input { padding: 8px; border-radius: 4px; border: 1px solid #ccc; }
.matrix-grid-editor { display: grid; gap: 5px; margin-bottom: 1rem; }
.matrix-grid-editor input {
    width: 45px; height: 45px; text-align: center;
    font-size: 1rem; border-radius: 4px; border: 1px solid #ccc;
}

@keyframes fadeIn { from { opacity: 0; transform: scale(0.95); } to { opacity: 1; transform: scale(1); } }

@media (max-width: 1024px) { 
    body{
        height:auto
    }
    .calculator-main { 
        grid-template-columns: 1fr; 
        grid-template-areas:
            "stored"
            "expression"
            "keypad"
            "result";
    } 
}

@media (max-width: 480px) {

    body { padding: 0.5rem;
    margin:0px }
    .card { padding: 1rem; }
    .keypad { gap: 5px; }
    .keypad-btn { font-size: 1rem; padding: 0.8rem; }
    .expression-display { font-size: 1.2rem; }
}