:root {
    --bg-color: #0f172a;
    --container-bg: #1e293b;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --success-color: #10b981;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem 1rem;
}

header {
    text-align: center;
    margin-bottom: 2rem;
    max-width: 500px;
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #3b82f6, #60a5fa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.tabs {
    display: flex;
    background-color: var(--container-bg);
    padding: 0.35rem;
    border-radius: 0.75rem;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
    width: 100%;
    max-width: 480px;
}

.tab-btn {
    flex: 1;
    background: none;
    border: none;
    color: var(--text-muted);
    padding: 0.75rem;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    border-radius: 0.5rem;
    transition: all 0.2s ease;
}

.tab-btn.active {
    background-color: var(--accent-color);
    color: var(--text-main);
}

.tool-container {
    background-color: var(--container-bg);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.75rem;
    width: 100%;
    max-width: 480px;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3);
    display: none;
}

.tool-container.active {
    display: block;
}

.form-group {
    margin-bottom: 1.25rem;
}

label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

input, textarea {
    width: 100%;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    color: var(--text-main);
    padding: 0.75rem;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

input:focus, textarea:focus {
    border-color: var(--accent-color);
}

textarea {
    resize: vertical;
    min-height: 120px;
}

.phone-input-container {
    display: flex;
    gap: 0.5rem;
}

.phone-input-container input[type="text"] {
    flex: 1;
}

.phone-input-container input#countryCode {
    width: 80px;
    text-align: center;
}

button.action-btn {
    width: 100%;
    background-color: var(--accent-color);
    color: var(--text-main);
    border: none;
    padding: 0.85rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background-color 0.2s;
    margin-top: 0.5rem;
}

button.action-btn:hover {
    background-color: var(--accent-hover);
}

.result-box {
    margin-top: 1.5rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--border-color);
    display: none;
}

.result-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.secondary-btn {
    flex: 1;
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.65rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-weight: 600;
    transition: background-color 0.2s;
}

.secondary-btn:hover {
    background-color: var(--border-color);
}

/* Counter Grid */
.counter-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

.counter-card {
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    padding: 1rem;
    border-radius: 0.5rem;
    text-align: center;
}

.counter-card .num {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent-color);
    margin-bottom: 0.25rem;
}

.counter-card .lbl {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
}

footer {
    margin-top: auto;
    padding-top: 2rem;
    font-size: 0.8rem;
    color: var(--text-muted);
    text-align: center;
}