:root {
    --primary-color: #2D5016;
    --secondary-color: #4A7C59;
    --accent-color: #8B7355;
    --success-color: #5C8001;
    --dark: #1F2421;
    --light: #F5F5F0;
    --gray: #6B7F6E;
    --forest-green: #2D5016;
    --sage-green: #4A7C59;
    --mountain-blue: #5B7C99;
    --earth-brown: #8B7355;
    --moss-green: #6B8E23;
    --gradient-primary: linear-gradient(135deg, #2D5016 0%, #4A7C59 100%);
    --gradient-earth: linear-gradient(135deg, #8B7355 0%, #A0826D 100%);
    --gradient-mountain: linear-gradient(135deg, #5B7C99 0%, #7A9BBC 100%);
    --gradient-trail: linear-gradient(135deg, #4A7C59 0%, #6B8E23 100%);
    --gradient-hero: linear-gradient(135deg, rgba(45, 80, 22, 0.9) 0%, rgba(74, 124, 89, 0.9) 100%);
    --shadow-sm: 0 2px 8px rgba(45, 80, 22, 0.08);
    --shadow-md: 0 4px 16px rgba(45, 80, 22, 0.12);
    --shadow-lg: 0 8px 32px rgba(45, 80, 22, 0.16);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background: linear-gradient(180deg, #f5f5f0 0%, #e8e8dd 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: var(--gradient-primary);
    color: white;
    padding: 1.5rem 0;
    box-shadow: var(--shadow-lg);
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    margin: 0;
    white-space: nowrap;
}

.logo-emoji {
    display: inline-block;
    margin-right: 0.5rem;
    animation: pulse 2s ease-in-out infinite;
}

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

nav {
    flex: 1;
    display: flex;
    justify-content: flex-end;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 0.5rem;
    margin: 0;
    padding: 0;
    align-items: center;
}

nav li {
    position: relative;
}

nav a {
    color: white;
    text-decoration: none;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    transition: var(--transition);
    font-weight: 500;
    position: relative;
    overflow: hidden;
    display: block;
    white-space: nowrap;
}

nav a::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.1);
    transition: var(--transition);
    z-index: 0;
}

nav a:hover::before {
    left: 0;
}

nav a:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-2px);
}

nav a.active {
    background: var(--gradient-trail);
    box-shadow: 0 4px 12px rgba(107, 142, 35, 0.4);
}

/* Dropdown menu */
.dropdown {
    position: relative;
}

.dropdown-toggle {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.dropdown-toggle::after {
    content: '▼';
    font-size: 0.7rem;
    transition: var(--transition);
}

.dropdown:hover .dropdown-toggle::after {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    margin-top: 0.5rem;
    background: white;
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: var(--transition);
    z-index: 1000;
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu a {
    color: var(--dark);
    padding: 0.75rem 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    border-radius: 0;
    background: transparent;
}

.dropdown-menu a:first-child {
    border-radius: 12px 12px 0 0;
}

.dropdown-menu a:last-child {
    border-radius: 0 0 12px 12px;
}

.dropdown-menu a:hover {
    background: var(--light);
    transform: translateY(0);
}

.dropdown-menu a.active {
    background: linear-gradient(135deg, rgba(45, 80, 22, 0.1) 0%, rgba(74, 124, 89, 0.1) 100%);
    color: var(--forest-green);
    font-weight: 600;
    box-shadow: none;
}

.dropdown-menu .menu-icon {
    font-size: 1.2rem;
}

/* Main Content */
main {
    min-height: calc(100vh - 200px);
    padding: 2rem 0;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 4rem 2rem;
    background: linear-gradient(135deg, rgba(45, 80, 22, 0.05) 0%, rgba(74, 124, 89, 0.08) 100%);
    border-radius: 24px;
    margin-bottom: 3rem;
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(74, 124, 89, 0.1) 0%, transparent 70%);
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    33% { transform: translate(30px, -30px) rotate(120deg); }
    66% { transform: translate(-20px, 20px) rotate(240deg); }
}

.hero h2 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 800;
    letter-spacing: -1px;
    position: relative;
    z-index: 1;
}

.hero p {
    font-size: 1.3rem;
    color: var(--gray);
    position: relative;
    z-index: 1;
    max-width: 600px;
    margin: 0 auto;
}

/* Utilities Grid */
.utilities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.utility-card {
    background: white;
    padding: 2.5rem;
    border-radius: 20px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.utility-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient-trail);
    transform: scaleX(0);
    transition: var(--transition);
}

.utility-card:hover::before {
    transform: scaleX(1);
}

.utility-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

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

.utility-card h3 {
    color: var(--dark);
    margin-bottom: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
}

.utility-card p {
    color: var(--gray);
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    background: var(--gradient-trail);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    transition: var(--transition);
    font-weight: 600;
    box-shadow: var(--shadow-sm);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--gradient-earth);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--forest-green);
    color: var(--forest-green);
}

.btn-outline:hover {
    background: var(--forest-green);
    color: white;
}

/* Utilities Section */
.utilities-section {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.utility-section {
    margin-bottom: 2rem;
}

.utility-section h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
    border-bottom: 2px solid #3498db;
    padding-bottom: 0.5rem;
}

.utility-section ul {
    list-style: none;
    padding-left: 1rem;
}

.utility-section li {
    padding: 0.5rem 0;
    color: #666;
}

.utility-section li:before {
    content: "▸ ";
    color: #3498db;
    font-weight: bold;
}

/* About Content */
.about-content {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.about-content h3 {
    color: #2c3e50;
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
}

/* Error Page */
.error-page {
    text-align: center;
    padding: 3rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.error-page h2 {
    color: #e74c3c;
    margin-bottom: 1rem;
}

/* Converter Tool */
.converter-tool {
    background: white;
    padding: 3rem;
    border-radius: 24px;
    box-shadow: var(--shadow-md);
    margin: 2rem 0;
}

.converter-tool h2 {
    color: var(--dark);
    margin-bottom: 0.5rem;
    font-size: 2rem;
    font-weight: 700;
}

.converter-tool h3 {
    color: var(--dark);
    margin-bottom: 2rem;
    font-size: 1.5rem;
    font-weight: 700;
}

.converter-tool .subtitle {
    color: var(--gray);
    margin-bottom: 2rem;
}

.input-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.converter-grid {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 2rem;
    align-items: center;
    margin: 2rem 0;
}

.input-group {
    background: var(--light);
    padding: 2rem;
    border-radius: 16px;
    border: 2px solid transparent;
    transition: var(--transition);
}

.input-group.full-width {
    grid-column: 1 / -1;
}

.input-group:focus-within {
    border-color: var(--sage-green);
    background: white;
    box-shadow: var(--shadow-sm);
}

.input-group label {
    display: block;
    font-weight: 600;
    color: var(--dark);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.input-group input,
.input-group select {
    width: 100%;
    padding: 1rem;
    font-size: 1.5rem;
    border: none;
    background: transparent;
    color: var(--dark);
    font-weight: 600;
    outline: none;
}

.input-group select {
    font-size: 1rem;
    margin-top: 0.5rem;
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    cursor: pointer;
}

.converter-icon {
    font-size: 2rem;
    color: var(--sage-green);
    animation: pulse 2s ease-in-out infinite;
}

.result-display {
    background: linear-gradient(135deg, rgba(45, 80, 22, 0.08) 0%, rgba(74, 124, 89, 0.12) 100%);
    padding: 2rem;
    border-radius: 16px;
    text-align: center;
    margin: 2rem 0;
}

.result-display .label {
    color: var(--gray);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 0.5rem;
}

.result-display .value {
    font-size: 3rem;
    font-weight: 700;
    background: var(--gradient-trail);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.quick-conversions {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-top: 2rem;
}

.quick-conversion-card {
    background: var(--light);
    padding: 1.5rem;
    border-radius: 12px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.quick-conversion-card:hover {
    background: white;
    box-shadow: var(--shadow-sm);
    transform: translateY(-2px);
}

.quick-conversion-card .emoji {
    font-size: 2rem;
    display: block;
    margin-bottom: 0.5rem;
}

.quick-conversion-card .title {
    font-weight: 600;
    color: var(--dark);
    font-size: 0.9rem;
}

.quick-conversion-card button {
    transition: var(--transition);
}

.quick-conversion-card .edit-btn:hover {
    background: var(--sage-green) !important;
    color: white !important;
    border-color: var(--sage-green) !important;
}

.quick-conversion-card input:focus {
    outline: none;
    border-color: var(--forest-green);
    box-shadow: 0 0 0 3px rgba(45, 80, 22, 0.1);
}

/* Footer */
footer {
    background: linear-gradient(135deg, var(--dark) 0%, #2d2d44 100%);
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
    position: relative;
    overflow: hidden;
}

footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--gradient-trail);
}

footer p {
    opacity: 0.8;
}

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

.fade-in-up {
    animation: fadeInUp 0.6s ease-out forwards;
}

/* Responsive */
@media (max-width: 968px) {
    .converter-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .converter-icon {
        transform: rotate(90deg);
    }
}

@media (max-width: 968px) {
    header .container {
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }
    
    header h1 {
        font-size: 1.5rem;
    }
    
    nav {
        justify-content: center;
        width: 100%;
    }
    
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.5rem;
    }
    
    nav a {
        padding: 0.6rem 1.2rem;
        font-size: 0.9rem;
    }
    
    /* Mobile dropdown */
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        margin-top: 0.5rem;
        display: none;
    }
    
    .dropdown:hover .dropdown-menu,
    .dropdown.active .dropdown-menu {
        display: block;
    }
}

@media (max-width: 768px) {
    header h1 {
        font-size: 1.3rem;
    }
    
    .hero h2 {
        font-size: 2.5rem;
    }
    
    .hero p {
        font-size: 1.1rem;
    }
    
    .utilities-grid {
        grid-template-columns: 1fr;
    }
    
    .converter-tool {
        padding: 1.5rem;
    }
    
    .result-display .value {
        font-size: 2rem;
    }
}

/* Loading State */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(45, 80, 22, 0.3);
    border-radius: 50%;
    border-top-color: var(--forest-green);
    animation: spin 1s ease-in-out infinite;
}

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

/* Tooltips */
.tooltip {
    position: relative;
    cursor: help;
}

.tooltip::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-8px);
    padding: 0.5rem 1rem;
    background: var(--dark);
    color: white;
    border-radius: 8px;
    font-size: 0.875rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
}

.tooltip:hover::after {
    opacity: 1;
    transform: translateX(-50%) translateY(-12px);
}