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

body {
    font-family: 'Segoe UI', Arial, sans-serif;
    min-height: 100vh;
    padding: 20px;
    
    /* Custom College Background Image */
    background: 
        linear-gradient(rgba(44, 62, 80, 0.7), rgba(52, 73, 94, 0.7)),
        url('students.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
}

.container {
    max-width: 450px;
    margin: 0 auto;
    padding-top: 20px;
}

.header {
    text-align: center;
    margin-bottom: 25px;
    background: linear-gradient(135deg, rgba(255,255,255,0.95) 0%, rgba(248,249,255,0.95) 100%);
    backdrop-filter: blur(10px);
    padding: 25px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
    border: 2px solid rgba(255,107,107,0.2);
    position: relative;
    overflow: hidden;
}

.header::before {
    content: '✨';
    position: absolute;
    top: 15px;
    right: 20px;
    font-size: 1.5rem;
    animation: sparkle 2s ease-in-out infinite;
}


@keyframes sparkle {
    0%, 100% { 
        opacity: 0.3;
        transform: scale(1);
    }
    50% { 
        opacity: 1;
        transform: scale(1.2);
    }
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 10px;
}

.logo-image {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    transition: transform 0.3s ease;
}

.logo-image:hover {
    transform: scale(1.1) rotate(5deg);
}

.logo h1 {
    color: #ff6b6b;
    font-size: 2.5rem;
    font-weight: bold;
    margin-bottom: 0;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: colorShift 3s ease-in-out infinite;
}

@keyframes colorShift {
    0%, 100% { 
        background: linear-gradient(45deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
    }
    50% { 
        background: linear-gradient(45deg, #4ecdc4, #45b7d1, #96ceb4, #ff6b6b);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
    }
}

.subtitle {
    color: #4a5568;
    font-size: 1.1rem;
    font-weight: 500;
    position: relative;
    z-index: 2;
}

.calculator-card {
    background: white;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.2);
    margin-bottom: 20px;
    border: 3px solid transparent;
    background-clip: padding-box;
    position: relative;
}

.calculator-card::before {
    content: '';
    position: absolute;
    top: -3px;
    left: -3px;
    right: -3px;
    bottom: -3px;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4);
    border-radius: 23px;
    z-index: -1;
    animation: borderGlow 3s ease-in-out infinite;
}

@keyframes borderGlow {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

.calc-header {
    text-align: center;
    margin-bottom: 25px;
}

.calc-header h2 {
    color: #2d3748;
    font-size: 1.8rem;
    margin-bottom: 8px;
    font-weight: 700;
}

.calc-header p {
    color: #718096;
    font-size: 1rem;
}

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

.input-group label {
    display: block;
    color: #2d3748;
    font-weight: 600;
    margin-bottom: 8px;
    font-size: 1rem;
}

.input-group input {
    width: 100%;
    padding: 15px;
    border: 3px solid #e2e8f0;
    border-radius: 12px;
    font-size: 1rem;
    background: #f7fafc;
    transition: all 0.3s ease;
}

.input-group input:focus {
    outline: none;
    border-color: #ff6b6b;
    background: white;
    box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.1);
    transform: translateY(-1px);
}

.input-group input[readonly] {
    background: linear-gradient(135deg, #fed7d7 0%, #fbb6ce 100%);
    border-color: #fc8181;
    color: #2d3748;
    font-weight: 600;
}

.input-group input[type="number"]#threshold {
    background: linear-gradient(135deg, #fff6f6 0%, #ffe6e6 100%);
    border-color: #ff6b6b;
    color: #2d3748;
    font-weight: 600;
}

.input-group input[type="number"]#threshold:focus {
    background: white;
    box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.2);
}

.button-group {
    display: flex;
    gap: 15px;
    margin-top: 25px;
}

.btn-calculate, .btn-reset {
    flex: 1;
    padding: 15px 20px;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn-calculate {
    background: linear-gradient(135deg, #ff6b6b 0%, #4ecdc4 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(255,107,107,0.4);
}

.btn-calculate:hover {
    background: linear-gradient(135deg, #ff5252 0%, #26d0ce 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255,107,107,0.5);
}

.btn-reset {
    background: linear-gradient(135deg, #45b7d1 0%, #96ceb4 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(69,183,209,0.4);
}

.btn-reset:hover {
    background: linear-gradient(135deg, #3498db 0%, #7fb3d3 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(69,183,209,0.5);
}

.results-container {
    background: white;
    border-radius: 20px;
    padding: 25px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.2);
    border: 3px solid transparent;
    background-clip: padding-box;
    position: relative;
}

.results-container::before {
    content: '';
    position: absolute;
    top: -3px;
    left: -3px;
    right: -3px;
    bottom: -3px;
    background: linear-gradient(45deg, #4ecdc4, #45b7d1, #96ceb4, #ff6b6b);
    border-radius: 23px;
    z-index: -1;
    animation: borderGlow 3s ease-in-out infinite 1.5s;
}

.attendance-status {
    text-align: center;
    margin-bottom: 20px;
}

.status-icon {
    font-size: 2.5rem;
    margin-bottom: 10px;
    display: block;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(-10px); }
    60% { transform: translateY(-5px); }
}

.attendance-percentage {
    font-size: 2.8rem;
    font-weight: bold;
    margin: 10px 0;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
}

.percentage-good { 
    background: linear-gradient(45deg, #48bb78, #4ecdc4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.percentage-warning { 
    background: linear-gradient(45deg, #ed8936, #ff6b6b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.percentage-danger { 
    background: linear-gradient(45deg, #f56565, #ff6b6b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.status-message {
    font-size: 1.1rem;
    font-weight: 600;
    padding: 15px 20px;
    border-radius: 12px;
    margin-bottom: 20px;
}

.status-good {
    background: linear-gradient(135deg, #c6f6d5 0%, #9ae6b4 100%);
    color: #22543d;
    border-left: 4px solid #48bb78;
}

.status-warning {
    background: linear-gradient(135deg, #feebc8 0%, #fbd38d 100%);
    color: #744210;
    border-left: 4px solid #ed8936;
}

.status-danger {
    background: linear-gradient(135deg, #fed7d7 0%, #feb2b2 100%);
    color: #742a2a;
    border-left: 4px solid #f56565;
}

.breakdown-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
    margin: 20px 0;
}

.breakdown-item {
    text-align: center;
    padding: 18px 12px;
    border-radius: 12px;
    color: white;
    font-weight: 600;
    transition: transform 0.3s ease;
    position: relative;
    overflow: hidden;
}

.breakdown-item:hover {
    transform: translateY(-3px);
}

.breakdown-total { 
    background: linear-gradient(135deg, #5a67d8 0%, #667eea 100%);
    box-shadow: 0 4px 15px rgba(90,103,216,0.3);
}

.breakdown-attended { 
    background: linear-gradient(135deg, #48bb78 0%, #4ecdc4 100%);
    box-shadow: 0 4px 15px rgba(72,187,120,0.3);
}

.breakdown-absent { 
    background: linear-gradient(135deg, #f56565 0%, #ff6b6b 100%);
    box-shadow: 0 4px 15px rgba(245,101,101,0.3);
}

.breakdown-item .label {
    font-size: 0.9rem;
    opacity: 0.9;
}

.breakdown-item .value {
    font-size: 1.8rem;
    font-weight: bold;
    margin-top: 5px;
}

.skip-section {
    background: linear-gradient(135deg, #c6f6d5 0%, #9ae6b4 100%);
    border-radius: 15px;
    padding: 20px;
    margin: 20px 0;
    border-left: 5px solid #48bb78;
    position: relative;
}

.skip-section.warning-skip {
    background: linear-gradient(135deg, #feebc8 0%, #fbd38d 100%);
    border-left-color: #ed8936;
}

.skip-section::before {
    content: '🎯';
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 1.5rem;
    opacity: 0.4;
}

.skip-title {
    color: #22543d;
    font-size: 1.3rem;
    font-weight: bold;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.warning-skip .skip-title {
    color: #dd6b20;
}

.skip-classes {
    background: rgba(255,255,255,0.9);
    padding: 15px;
    border-radius: 10px;
    margin: 15px 0;
    font-weight: 600;
    border-left: 4px solid #4ecdc4;
    font-size: 1.1rem;
}

.skip-warning {
    background: rgba(255,235,200,0.8);
    padding: 12px;
    border-radius: 8px;
    margin: 8px 0;
    font-size: 0.95rem;
    color: #744210;
}

.skip-advice {
    background: rgba(255,255,255,0.9);
    padding: 12px;
    border-radius: 8px;
    margin: 10px 0;
    font-weight: 600;
    color: #2d3748;
}

.recovery-section {
    background: linear-gradient(135deg, #feebc8 0%, #fbd38d 100%);
    border-radius: 15px;
    padding: 20px;
    margin: 20px 0;
    border-left: 5px solid #ed8936;
    position: relative;
}

.recovery-section::before {
    content: '🎯';
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 1.5rem;
    opacity: 0.4;
}

.recovery-title {
    color: #dd6b20;
    font-size: 1.3rem;
    font-weight: bold;
    margin-bottom: 10px;
}

.needed-classes {
    background: rgba(255,255,255,0.9);
    padding: 15px;
    border-radius: 10px;
    margin: 15px 0;
    font-weight: 600;
    border-left: 4px solid #4ecdc4;
}

.alternatives h4 {
    color: #dd6b20;
    margin: 15px 0 10px 0;
    font-size: 1.1rem;
}

.alternatives ul {
    list-style: none;
    padding: 0;
}

.alternatives li {
    padding: 6px 0;
    color: #4a5568;
    position: relative;
    padding-left: 20px;
}

.alternatives li:before {
    content: "💡";
    position: absolute;
    left: 0;
    top: 4px;
}

.motivation-section {
    background: linear-gradient(135deg, #bee3f8 0%, #90cdf4 100%);
    border-radius: 12px;
    padding: 18px;
    margin: 20px 0;
    text-align: center;
    color: #2c5282;
    font-weight: 600;
    font-size: 1.1rem;
    border-left: 4px solid #45b7d1;
}

.footer {
    text-align: center;
    color: white;
    font-size: 1.1rem;
    margin-top: 25px;
    opacity: 0.9;
    font-weight: 500;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
}

.developer-credit {
    text-align: center;
    margin-top: 30px;
    padding: 15px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.developer-credit p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9rem;
    margin: 0;
    font-style: italic;
    letter-spacing: 0.5px;
}

.developer-credit .heart {
    color: #ff6b6b;
    animation: heartbeat 1.5s ease-in-out infinite;
    display: inline-block;
    margin: 0 3px;
}

@keyframes heartbeat {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

@media (max-width: 600px) {
    .container {
        padding: 10px;
    }
    
    .logo {
        flex-direction: column;
        gap: 10px;
    }
    
    .logo h1 {
        font-size: 2rem;
    }
    
    .breakdown-grid {
        grid-template-columns: 1fr;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .header::before,
    .header::after {
        display: none;
    }
}