* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    min-height: 100vh;
    color: #fff;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2.5rem;
    color: #00d4ff;
    text-shadow: 0 0 10px rgba(0, 212, 255, 0.5);
}

h2 {
    color: #00d4ff;
    margin-bottom: 15px;
}

.main-content {
    display: flex;
    gap: 30px;
    margin-bottom: 40px;
    flex-wrap: wrap;
    justify-content: center;
}

.simulation-area {
    background: #0f0f23;
    border-radius: 15px;
    padding: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

#pendulumCanvas {
    display: block;
    border-radius: 10px;
    background: linear-gradient(180deg, #1a1a3e 0%, #0d0d1a 100%);
}

.controls-area {
    background: #0f0f23;
    border-radius: 15px;
    padding: 25px;
    min-width: 320px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.control-group {
    margin-bottom: 20px;
}

.control-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #b8b8d1;
}

.control-group select,
.control-group input[type="number"] {
    width: 100%;
    padding: 10px 15px;
    border: 2px solid #2a2a4a;
    border-radius: 8px;
    background: #1a1a3e;
    color: #fff;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.control-group select:focus,
.control-group input[type="number"]:focus {
    outline: none;
    border-color: #00d4ff;
}

.control-group input[type="range"] {
    width: calc(100% - 50px);
    vertical-align: middle;
}

#angleValue {
    display: inline-block;
    width: 40px;
    text-align: right;
    color: #00d4ff;
    font-weight: bold;
}

.button-group {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    flex: 1;
}

.btn-primary {
    background: linear-gradient(135deg, #00d4ff 0%, #0099cc 100%);
    color: #000;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0, 212, 255, 0.4);
}

.btn-primary:disabled {
    background: #555;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.btn-secondary {
    background: #2a2a4a;
    color: #fff;
}

.btn-secondary:hover {
    background: #3a3a5a;
}

.btn-success {
    background: linear-gradient(135deg, #00ff88 0%, #00cc6a 100%);
    color: #000;
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0, 255, 136, 0.4);
}

.btn-danger {
    background: linear-gradient(135deg, #ff4444 0%, #cc0000 100%);
    color: #fff;
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(255, 68, 68, 0.4);
}

.timer-display {
    background: #1a1a3e;
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    margin-bottom: 20px;
}

.timer-label {
    font-size: 0.9rem;
    color: #b8b8d1;
    margin-bottom: 5px;
}

.timer-value {
    font-size: 2.5rem;
    font-family: 'Courier New', monospace;
    color: #00ff88;
    text-shadow: 0 0 10px rgba(0, 255, 136, 0.5);
}

.results-display {
    background: #1a1a3e;
    border-radius: 10px;
    padding: 20px;
    border: 2px solid #00d4ff;
}

.results-display h3 {
    color: #00d4ff;
    margin-bottom: 15px;
}

.results-display p {
    margin-bottom: 10px;
    color: #b8b8d1;
}

.results-display span {
    color: #00ff88;
}

.results-display .btn {
    margin-top: 15px;
    width: 100%;
}

.data-table-section {
    background: #0f0f23;
    border-radius: 15px;
    padding: 25px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

#dataTable {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

#dataTable th,
#dataTable td {
    padding: 12px 20px;
    text-align: center;
    border-bottom: 1px solid #2a2a4a;
}

#dataTable th {
    background: #1a1a3e;
    color: #00d4ff;
    font-weight: 600;
}

#dataTable tbody tr:hover {
    background: #1a1a3e;
}

#dataTable td {
    color: #b8b8d1;
}

.btn-remove {
    padding: 5px 12px;
    border: none;
    border-radius: 5px;
    background: #ff4444;
    color: #fff;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-remove:hover {
    background: #cc0000;
    transform: scale(1.05);
}

.data-table-section .btn {
    margin-right: 10px;
}

/* Analysis Section */
.analysis-section {
    background: #0f0f23;
    border-radius: 15px;
    padding: 25px;
    margin-top: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.analysis-info {
    color: #b8b8d1;
    margin-bottom: 15px;
    font-style: italic;
}

.analysis-results {
    display: flex;
    gap: 30px;
    margin-top: 20px;
    flex-wrap: wrap;
}

.plot-container {
    background: #1a1a3e;
    border-radius: 10px;
    padding: 15px;
}

#plotCanvas {
    display: block;
    background: #0d0d1a;
    border-radius: 8px;
}

.fit-results {
    flex: 1;
    min-width: 280px;
    background: #1a1a3e;
    border-radius: 10px;
    padding: 20px;
}

.fit-results h3 {
    color: #00d4ff;
    margin-bottom: 15px;
}

.fit-results p {
    margin-bottom: 10px;
    color: #b8b8d1;
}

.fit-results span {
    color: #00ff88;
}

.equation {
    font-size: 1.3rem;
    font-family: 'Courier New', monospace;
    color: #fff !important;
    background: #0d0d1a;
    padding: 10px 15px;
    border-radius: 8px;
    margin-bottom: 20px !important;
}

.gravity-result {
    margin-top: 20px;
    padding-top: 15px;
    border-top: 1px solid #2a2a4a;
}

.gravity-value {
    font-size: 1.4rem;
    color: #00ff88 !important;
    font-weight: bold;
}

.theoretical {
    font-size: 0.9rem;
    color: #888 !important;
    margin-top: 10px;
}

@media (max-width: 768px) {
    .main-content {
        flex-direction: column;
        align-items: center;
    }

    .controls-area {
        min-width: 100%;
    }

    #pendulumCanvas {
        width: 100%;
        height: auto;
    }
}