/* ============================================
   CSS VARIABLES & DESIGN TOKENS
   ============================================ */
:root {
    /* Colors */
    --primary-start: #6366f1;
    --primary-end: #8b5cf6;
    --primary-gradient: linear-gradient(135deg, var(--primary-start), var(--primary-end));

    --danger-color: #f97316;
    --danger-light: #fb923c;
    --success-color: #10b981;
    --warning-color: #fbbf24;

    --bg-dark: #0f172a;
    --bg-darker: #020617;
    --bg-card: rgba(255, 255, 255, 0.05);
    --bg-card-hover: rgba(255, 255, 255, 0.08);

    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;

    --border-color: rgba(255, 255, 255, 0.1);
    --border-focus: rgba(139, 92, 246, 0.5);

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Shadows */
    --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, 0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 40px rgba(139, 92, 246, 0.3);
}

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

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background-color: var(--bg-darker);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
}

/* ============================================
   BACKGROUND EFFECTS
   ============================================ */
.bg-gradient {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(139, 92, 246, 0.15) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

.bg-orbs {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    pointer-events: none;
    z-index: 0;
}

.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.3;
    animation: float 20s infinite ease-in-out;
}

.orb-1 {
    width: 400px;
    height: 400px;
    background: var(--primary-gradient);
    top: -200px;
    left: -200px;
    animation-delay: 0s;
}

.orb-2 {
    width: 500px;
    height: 500px;
    background: linear-gradient(135deg, #8b5cf6, #ec4899);
    bottom: -250px;
    right: -250px;
    animation-delay: 7s;
}

.orb-3 {
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, #06b6d4, #3b82f6);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: 14s;
}

@keyframes float {

    0%,
    100% {
        transform: translate(0, 0) scale(1);
    }

    33% {
        transform: translate(50px, -50px) scale(1.1);
    }

    66% {
        transform: translate(-50px, 50px) scale(0.9);
    }
}

/* ============================================
   CONTAINER & LAYOUT
   ============================================ */
.container {
    position: relative;
    z-index: 1;
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
}

/* ============================================
   HEADER
   ============================================ */
.header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.logo-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.logo {
    width: 60px;
    height: 60px;
    filter: drop-shadow(0 0 20px rgba(139, 92, 246, 0.5));
    animation: pulse 3s infinite ease-in-out;
}

.logo-icon {
    font-size: 60px;
    filter: drop-shadow(0 0 20px rgba(139, 92, 246, 0.5));
    animation: pulse 3s infinite ease-in-out;
    line-height: 1;
}

@keyframes pulse {

    0%,
    100% {
        transform: scale(1);
    }

    50% {
        transform: scale(1.05);
    }
}

h1 {
    font-size: clamp(1.75rem, 5vw, 2.5rem);
    font-weight: 800;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 1.125rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* ============================================
   INTRO SECTION
   ============================================ */
.intro {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.intro p {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.intro strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* ============================================
   CALCULATOR CARD
   ============================================ */
.calculator-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
    transition: box-shadow var(--transition-base);
}

.calculator-card:hover {
    box-shadow: var(--shadow-xl), var(--shadow-glow);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.card-header h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.currency-selector {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.currency-selector label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.currency-select {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-primary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

/* Fix dropdown options visibility in dark mode */
.currency-select option {
    background: var(--bg-dark);
    color: var(--text-primary);
    padding: var(--spacing-sm);
}

.currency-select:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--border-focus);
}

.currency-select:focus {
    outline: none;
    border-color: var(--primary-end);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.2);
}

/* ============================================
   SUBSCRIPTION ROWS
   ============================================ */
.subscriptions-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.subscription-row {
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: var(--spacing-md);
    align-items: center;
    animation: slideIn var(--transition-base);
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.input-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.input-field {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 500;
    transition: all var(--transition-fast);
    font-family: 'Inter', sans-serif;
}

.input-field:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--border-focus);
}

.input-field:focus {
    outline: none;
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--primary-end);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.2);
}

.input-field::placeholder {
    color: var(--text-muted);
}

.cost-input-wrapper {
    position: relative;
}

.currency-symbol {
    position: absolute;
    left: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    font-weight: 600;
    pointer-events: none;
    min-width: 1.5rem;
    display: inline-block;
}

.cost-input {
    padding-left: 2.75rem;
    font-variant-numeric: tabular-nums;
}

.btn-remove {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #ef4444;
    border-radius: var(--radius-sm);
    padding: var(--spacing-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    align-self: end;
}

.btn-remove:hover {
    background: rgba(239, 68, 68, 0.2);
    border-color: #ef4444;
    transform: scale(1.05);
}

.btn-remove:active {
    transform: scale(0.95);
}

.btn-remove svg {
    width: 20px;
    height: 20px;
}

/* ============================================
   ACTION BUTTONS
   ============================================ */
.action-buttons {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
    font-family: 'Inter', sans-serif;
}

.btn:active {
    transform: scale(0.98);
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    box-shadow: var(--shadow-lg), 0 0 20px rgba(139, 92, 246, 0.4);
    transform: translateY(-2px);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--border-focus);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid transparent;
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    border-color: var(--border-color);
}

/* ============================================
   RESULTS SECTION
   ============================================ */
.results-section {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
}

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

.result-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    transition: all var(--transition-base);
}

.result-card:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.result-card-highlight {
    background: linear-gradient(135deg, rgba(249, 115, 22, 0.1), rgba(251, 146, 60, 0.1));
    border-color: rgba(249, 115, 22, 0.3);
}

.result-card-highlight:hover {
    background: linear-gradient(135deg, rgba(249, 115, 22, 0.15), rgba(251, 146, 60, 0.15));
    box-shadow: 0 0 30px rgba(249, 115, 22, 0.2);
}

.result-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-sm);
}

.result-value {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
    transition: all var(--transition-base);
}

.result-card-highlight .result-value {
    background: linear-gradient(135deg, var(--danger-color), var(--danger-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ============================================
   LEAK INDICATOR
   ============================================ */
.leak-indicator {
    text-align: center;
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    background: rgba(249, 115, 22, 0.05);
    border: 1px dashed rgba(249, 115, 22, 0.3);
    margin-bottom: var(--spacing-lg);
}

.leak-icon {
    width: 60px;
    height: 60px;
    margin-bottom: var(--spacing-md);
    animation: bounce 2s infinite;
}

.leak-icon-emoji {
    font-size: 60px;
    margin-bottom: var(--spacing-md);
    animation: bounce 2s infinite;
    line-height: 1;
}

@keyframes bounce {

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

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

.leak-message {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--danger-color);
    line-height: 1.5;
}

/* ============================================
   SHARE BUTTON
   ============================================ */
.btn-share {
    width: 100%;
    justify-content: center;
    background: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
    border: 1px solid rgba(16, 185, 129, 0.3);
    padding: var(--spacing-md) var(--spacing-lg);
}

.btn-share:hover {
    background: rgba(16, 185, 129, 0.2);
    border-color: var(--success-color);
    box-shadow: 0 0 20px rgba(16, 185, 129, 0.2);
}

/* ============================================
   FAQ SECTION
   ============================================ */
.faq-section {
    margin-bottom: var(--spacing-2xl);
}

.faq-section h2 {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.faq-item {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-base);
}

.faq-item:hover {
    background: var(--bg-card-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.faq-item h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.faq-item p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    text-align: center;
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--border-color);
}

.disclaimer {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.disclaimer strong {
    color: var(--text-secondary);
}

.footer-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    font-size: 0.875rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--primary-end);
}

.separator {
    color: var(--text-muted);
}

.copyright {
    color: var(--text-muted);
}

/* ============================================
   TOAST NOTIFICATION
   ============================================ */
.toast {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    background: var(--success-color);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: 600;
    transform: translateY(150%);
    transition: transform var(--transition-base);
    z-index: 1000;
}

.toast.show {
    transform: translateY(0);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 768px) {
    .container {
        padding: var(--spacing-lg) var(--spacing-md);
    }

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

    .btn-remove {
        width: 100%;
        justify-content: center;
    }

    .card-header {
        flex-direction: column;
        align-items: flex-start;
    }

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

    .result-value {
        font-size: 1.75rem;
    }

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

    .action-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.5rem;
    }

    .tagline {
        font-size: 1rem;
    }

    .logo {
        width: 50px;
        height: 50px;
    }

    .calculator-card,
    .results-section {
        padding: var(--spacing-lg);
    }

    .result-value {
        font-size: 1.5rem;
    }
}

/* ============================================
   ACCESSIBILITY
   ============================================ */
@media (prefers-reduced-motion: reduce) {

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus visible for keyboard navigation */
*:focus-visible {
    outline: 2px solid var(--primary-end);
    outline-offset: 2px;
}