/* ========================================
   SMART ALL-IN-ONE CALCULATOR - GLOBAL STYLES
   ========================================
   Purpose: Main stylesheet for the entire application
   Contains: Reset, Variables, Layout, Components, Responsive Design
   ======================================== */

/* ========================================
   CSS RESET & BASE STYLES
   ======================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #ffffff;
    min-height: 100vh;
}

/* ========================================
   CSS VARIABLES (Color Theme)
   ======================================== */
:root {
    /* Primary Colors */
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --accent-color: #f093fb;

    /* Neutral Colors */
    --white: #ffffff;
    --light-gray: #f8f9fa;
    --gray: #6c757d;
    --dark-gray: #343a40;
    --black: #000000;

    /* Category Colors */
    --education-color: #4CAF50;
    --finance-color: #FF9800;
    --daily-life-color: #2196F3;
    --math-science-color: #9C27B0;
    --business-color: #F44336;
    --smart-ai-color: #00BCD4;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;

    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
    --shadow-3d: 0 10px 30px rgba(0, 0, 0, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.08);
}

/* ========================================
   DASHBOARD CONTAINER
   ======================================== */
.dashboard-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-md);
    position: relative;
    perspective: 1400px;
}

/* ========================================
   HEADER SECTION
   ======================================== */
.header {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-lg);
    text-align: center;
}

.header-content {
    max-width: 800px;
    margin: 0 auto;
}

.logo {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.logo-icon {
    font-size: 3rem;
    animation: float 3s ease-in-out infinite;
}

/* Floating animation for logo icon */
@keyframes float {

    0%,
    100% {
        transform: translateY(0px);
    }

    50% {
        transform: translateY(-10px);
    }
}

.tagline {
    font-size: 1.1rem;
    color: var(--gray);
    font-weight: 300;
}

/* ========================================
   MAIN CONTENT AREA
   ======================================== */
.main-content {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
    margin-bottom: var(--spacing-lg);
}

/* ========================================
   WELCOME SECTION
   ======================================== */
.welcome-section {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px solid var(--light-gray);
}

.welcome-section h2 {
    font-size: 2rem;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-sm);
}

.welcome-section p {
    font-size: 1.1rem;
    color: var(--gray);
    max-width: 700px;
    margin: 0 auto;
}

/* ========================================
   CATEGORIES GRID
   ======================================== */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

/* ========================================
   CATEGORY CARD COMPONENT
   ======================================== */
.category-card {
    background: var(--white);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

/* Hover effect for cards */
.category-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

/* Card icon styling */
.card-icon {
    font-size: 3.5rem;
    margin-bottom: var(--spacing-md);
    display: block;
    transition: transform 0.3s ease;
}

.category-card:hover .card-icon {
    transform: scale(1.1) rotate(5deg);
}

/* Card title */
.card-title {
    font-size: 1.5rem;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

/* Card description */
.card-description {
    color: var(--gray);
    margin-bottom: var(--spacing-md);
    font-size: 0.95rem;
}

/* Card features list */
.card-features {
    list-style: none;
    margin-bottom: var(--spacing-md);
}

.card-features li {
    padding: var(--spacing-xs) 0;
    color: var(--gray);
    font-size: 0.9rem;
    position: relative;
    padding-left: var(--spacing-md);
}

.card-features li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Card button */
.card-button {
    display: inline-block;
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    background: linear-gradient(120deg, #00d2ff 0%, #3a47d5 50%, #7f5af0 100%);
    color: var(--white);
    text-decoration: none;
    border-radius: 14px;
    text-align: center;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 12px 24px rgba(63, 81, 181, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.25);
}

.card-button:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 20px 30px rgba(63, 81, 181, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.35);
}

/* Category-specific card colors */
.education-card:hover {
    border-color: var(--education-color);
}

.finance-card:hover {
    border-color: var(--finance-color);
}

.daily-life-card:hover {
    border-color: var(--daily-life-color);
}

.math-science-card:hover {
    border-color: var(--math-science-color);
}

.business-card:hover {
    border-color: var(--business-color);
}

.smart-ai-card:hover {
    border-color: var(--smart-ai-color);
}

/* ========================================
   FEATURES HIGHLIGHT SECTION
   ======================================== */
.features-highlight {
    text-align: center;
    padding: var(--spacing-xl) 0;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), transparent);
}

.features-highlight h2 {
    font-size: 2rem;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-lg);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
}

.feature-item {
    padding: var(--spacing-md);
}

.feature-icon {
    font-size: 2.5rem;
    display: block;
    margin-bottom: var(--spacing-sm);
}

.feature-item h4 {
    font-size: 1.2rem;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-xs);
}

.feature-item p {
    color: var(--gray);
    font-size: 0.9rem;
}

/* ========================================
   FOOTER SECTION
   ======================================== */
.footer {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    box-shadow: var(--shadow-md);
}

.footer-content p {
    color: var(--gray);
    margin-bottom: var(--spacing-xs);
}

.footer-note {
    font-size: 0.9rem;
    font-style: italic;
}

/* ========================================
   FOOTER SOCIAL MEDIA ICONS
   ======================================== */
.footer-social {
    margin-top: var(--spacing-md);
    text-align: center;
}

.social-icons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background: var(--light-gray);
    color: var(--dark-gray);
    transition: all 0.3s ease;
    text-decoration: none;
}

.social-icon:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.social-icon.github:hover {
    background: #333;
    color: var(--white);
}

.social-icon.linkedin:hover {
    background: #0077b5;
    color: var(--white);
}

.social-icon.email:hover {
    background: #ea4335;
    color: var(--white);
}

.social-icon.instagram:hover {
    background: linear-gradient(45deg, #f09433 0%, #e6683c 25%, #dc2743 50%, #cc2366 75%, #bc1888 100%);
    color: var(--white);
}

/* ========================================
   SECTION PAGE STYLES (for all section pages)
   ======================================== */
.section-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md);
}

.section-header {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-lg);
}

.back-button {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--light-gray);
    color: var(--dark-gray);
    text-decoration: none;
    border-radius: var(--radius-sm);
    font-weight: 600;
    transition: all 0.3s ease;
    margin-bottom: var(--spacing-md);
}

.back-button:hover {
    background: var(--gray);
    color: var(--white);
    transform: translateX(-5px);
}

.section-title {
    font-size: 2.5rem;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.section-description {
    font-size: 1.1rem;
    color: var(--gray);
}

/* ========================================
   CALCULATOR CONTAINER
   ======================================== */
.calculators-container {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
}

.calculator-box {
    background: var(--light-gray);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.calculator-box:last-child {
    margin-bottom: 0;
}

.calculator-title {
    font-size: 1.5rem;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--primary-color);
}

/* ========================================
   FORM ELEMENTS
   ======================================== */
.form-group {
    margin-bottom: var(--spacing-md);
}

.form-label {
    display: block;
    font-weight: 600;
    color: var(--dark-gray);
    margin-bottom: var(--spacing-xs);
}

.form-input,
.form-select {
    width: 100%;
    padding: var(--spacing-sm);
    border: 2px solid var(--light-gray);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-input:focus,
.form-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--gray);
    color: var(--white);
}

.btn-secondary:hover {
    background: var(--dark-gray);
}

/* ========================================
   RESULT DISPLAY
   ======================================== */
.result-box {
    background: var(--white);
    border-left: 4px solid var(--primary-color);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    margin-top: var(--spacing-md);
}

.result-box.hidden {
    display: none;
}

.result-label {
    font-weight: 600;
    color: var(--gray);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.result-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
}

.result-message {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-weight: 500;
}

.result-message.success {
    background: #d4edda;
    color: #155724;
}

.result-message.warning {
    background: #fff3cd;
    color: #856404;
}

.result-message.info {
    background: #d1ecf1;
    color: #0c5460;
}

/* ========================================
   RESPONSIVE DESIGN - TABLET
   ======================================== */
@media (max-width: 768px) {
    .logo {
        font-size: 2rem;
    }

    .logo-icon {
        font-size: 2.5rem;
    }

    .tagline {
        font-size: 1rem;
    }

    .welcome-section h2 {
        font-size: 1.5rem;
    }

    .categories-grid {
        grid-template-columns: 1fr;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .main-content {
        padding: var(--spacing-lg);
    }
}

/* ========================================
   RESPONSIVE DESIGN - MOBILE
   ======================================== */
@media (max-width: 480px) {
    html {
        font-size: 14px;
    }

    .dashboard-container,
    .section-container {
        padding: var(--spacing-sm);
    }

    .header,
    .main-content,
    .footer {
        padding: var(--spacing-md);
    }

    .logo {
        font-size: 1.5rem;
        flex-direction: column;
    }

    .categories-grid {
        gap: var(--spacing-md);
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .section-title {
        font-size: 1.8rem;
    }
}

/* ========================================
   UTILITY CLASSES
   ======================================== */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

.mt-1 {
    margin-top: var(--spacing-sm);
}

.mt-2 {
    margin-top: var(--spacing-md);
}

.mt-3 {
    margin-top: var(--spacing-lg);
}

.mb-1 {
    margin-bottom: var(--spacing-sm);
}

.mb-2 {
    margin-bottom: var(--spacing-md);
}

.mb-3 {
    margin-bottom: var(--spacing-lg);
}

.hidden {
    display: none;
}

.visible {
    display: block;
}