/* ========================================
   internetgemein.de - Professional Calculator CSS
   ======================================== */

/* CSS Variables for consistent theming */
:root {
    --primary-color: #DD0000;
    --secondary-color: #e4d126;
    --accent-color: #FFCC00;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --text-dark: #000000;
    --text-light: #000000;
    --white: #ffffff;
    --border-color: #FFCC00;
    --success: #10b981;
    --warning: #f59e0b;
    --error: #ef4444;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--light-bg);
    overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
    color: var(--text-light);
}

a {
    color: var(--secondary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--primary-color);
}

/* Header Styles */
header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

header.scrolled {
    box-shadow: var(--shadow-lg);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    font-size: 2rem;
}

.logo h1 {
    color: var(--white);
    font-size: 1.5rem;
    margin: 0;
}

.logo small {
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.875rem;
    font-weight: 400;
}

/* Navigation */
nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    color: var(--white);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    transition: all 0.3s ease;
}

.nav-link:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--white);
    transform: translateY(-2px);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 0.25rem;
    cursor: pointer;
    padding: 0.5rem;
}

.menu-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--white);
    transition: all 0.3s ease;
    border-radius: 2px;
}

/* Main Content Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 4rem 2rem;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    margin-bottom: 3rem;
    border-radius: 1rem;
    box-shadow: var(--shadow-xl);
    animation: fadeInUp 0.8s ease;
}

.hero h1 {
    color: var(--white);
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.25rem;
    max-width: 700px;
    margin: 0 auto;
}

/* Calculator Grid */
.calculator-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
    animation: fadeIn 1s ease;
}

.calculator-card {
    background: var(--white);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.calculator-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--secondary-color);
}

.calculator-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.calculator-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

.calculator-card p {
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    min-height: 60px;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    border-radius: 0.5rem;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    box-shadow: var(--shadow-sm);
}

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

/* Calculator Page Styles */
.calculator-container {
    background: var(--white);
    border-radius: 1rem;
    padding: 3rem;
    box-shadow: var(--shadow-lg);
    margin: 2rem auto;
    max-width: 900px;
    animation: fadeInUp 0.6s ease;
}

.calculator-header {
    text-align: center;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--border-color);
}

.calculator-header h1 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.calculator-description {
    background: var(--light-bg);
    padding: 1.5rem;
    border-radius: 0.5rem;
    margin-bottom: 2rem;
    border-left: 4px solid var(--secondary-color);
}

.calculator-description h3 {
    color: var(--primary-color);
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

/* Form Styles */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
    font-weight: 500;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: all 0.3s ease;
    background-color: var(--white);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

/* Results Display */
.results {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    padding: 2rem;
    border-radius: 1rem;
    margin-top: 2rem;
    box-shadow: var(--shadow-lg);
    animation: slideInUp 0.5s ease;
}

.results h3 {
    color: var(--white);
    margin-bottom: 1.5rem;
    text-align: center;
}

.result-item {
    display: flex;
    justify-content: space-between;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    backdrop-filter: blur(10px);
}

.result-label {
    font-weight: 500;
}

.result-value {
    font-size: 1.25rem;
    font-weight: 700;
}

/* Table Styles */
.results-table {
    width: 100%;
    margin-top: 2rem;
    border-collapse: collapse;
    background: var(--white);
    border-radius: 0.5rem;
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.results-table th {
    background: var(--primary-color);
    color: var(--white);
    padding: 1rem;
    text-align: left;
    font-weight: 600;
}

.results-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.results-table tr:hover {
    background-color: var(--light-bg);
}

/* Footer */
footer {
    background: var(--dark-bg);
    color: var(--white);
    padding: 3rem 2rem 1.5rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3 {
    color: var(--white);
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: var(--white);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 1s ease;
}

.fade-in-up {
    animation: fadeInUp 0.8s ease;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

/* Responsive Design */
@media (max-width: 768px) {
    .header-container {
        flex-wrap: wrap;
        padding: 1rem;
    }

    nav {
        display: none;
        width: 100%;
        margin-top: 1rem;
    }

    nav.active {
        display: block;
    }

    nav ul {
        flex-direction: column;
        gap: 0.5rem;
    }

    .menu-toggle {
        display: flex;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .calculator-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .calculator-container {
        padding: 1.5rem;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    h3 { font-size: 1.5rem; }

    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 1rem;
    }

    .hero {
        padding: 2rem 1rem;
    }

    .calculator-card {
        padding: 1.5rem;
    }

    .result-item {
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* Loading State */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--white);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Alert Messages */
.alert {
    padding: 1rem 1.5rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    border-left: 4px solid;
}

.alert-success {
    background-color: rgba(16, 185, 129, 0.1);
    border-color: var(--success);
    color: var(--success);
}

.alert-warning {
    background-color: rgba(245, 158, 11, 0.1);
    border-color: var(--warning);
    color: var(--warning);
}

.alert-error {
    background-color: rgba(239, 68, 68, 0.1);
    border-color: var(--error);
    color: var(--error);
}